UNRAVELLING THE COMPLEXITIES SCIENCE PLAN FOR 2014-2019 SCIENCE PLAN FOR 2014-2019 - GFZ-Potsdam

Page created by Jennifer Perry
 
CONTINUE READING
UNRAVELLING THE COMPLEXITIES SCIENCE PLAN FOR 2014-2019 SCIENCE PLAN FOR 2014-2019 - GFZ-Potsdam
INTERNATIONAL
                                                   CONTINENTAL SCIENTIFIC
                                                   DRILLING PROGRAM

UNRAVELLING
   OF PLANET EARTH THE WORKINGS OF
   UNRAVELLING THE COMPLEXITIES

PLANET
   SCIENCE EARTH
           PLAN FOR 2014–2019
SCIENCE PLAN FOR 2014–2019

                    We invite you to think about why Earth Science
                    matters, and the often surprising ways in which it
                    affects our lives.
UNRAVELLING THE COMPLEXITIES SCIENCE PLAN FOR 2014-2019 SCIENCE PLAN FOR 2014-2019 - GFZ-Potsdam
UNRAVELLING THE COMPLEXITIES SCIENCE PLAN FOR 2014-2019 SCIENCE PLAN FOR 2014-2019 - GFZ-Potsdam
UNRAVELLING THE WORKINGS OF PLANET EARTH
SCIENCE PLAN FOR 2014–2019
edited by Horsfield, B., Knebel, C., Ludden, J. and Hyndman, R.
UNRAVELLING THE COMPLEXITIES SCIENCE PLAN FOR 2014-2019 SCIENCE PLAN FOR 2014-2019 - GFZ-Potsdam
4 EXECUTIVE SUMMARY
                                                                                                                  ICDP

 EXECUTIVE SUMMARY

Earth science goals                          The programme
Modern earth science has two basic           ICDP boasts a strong and active partici-      Through the unique
goals: seeking to unravel the histori-       pation of twenty-two member nations.          capacities of scientific
cal archives that are locked up in rocks     It has undertaken more than 30 drilling
                                                                                           drilling to provide
formed over the entire history of the        projects and run 75 workshops. Its cur-
Earth, and understanding the structure       rent budget of $3.5 million a year is a
                                                                                           exact, fundamental,
and dynamics of the active planet on         small fraction of that of the Internation-    and globally significant
which we live. To realise both goals sci-    al Ocean Discovery Program ( IODP ) or        knowledge of the
entific drilling is essential: it uncovers   other large earth science infrastructure      composition, structure,
rock archives containing the records of      projects. ICDP—already lean and mean
                                                                                           and processes of the
tectonic, climatic and biological cycles,    with a minimum of bureaucracy—is
and impacts from extraterrestrial bod-       making important ongoing changes to
                                                                                           Earth’s crust.
ies, from the present day, back into         its operations to build an even stronger
deep time. Targeted scientific drilling      technical base and reshaping its man-
allows us to sample, measure and moni-       agement structure to be more effective.
tor the Earth to help develop sustain-       Networking with other major earth sci-
able resources. Drillhole observatories      ence programmes is being strengthened,
give key insights into Earth’s internal      and bridges with the private and gov-
dynamic activities, such as fluctuations     ernment sector built, thus strengthening
in heat and the magnetic fields or earth-    ICDP’s economic and societal portfolio.
quakes and volcanoes.
                                             The spectrum
It would be impossible to undertake          ICDP has a broad portfolio centred on
modern earth science research with-          scientific drilling. Firstly, it provides a
out scientific drilling. The International   strategy for successful science deliv-
Continental Scientific Drilling Program      ery by funding workshops, leading and
( ICDP ) has played a primary role over      supporting technological innovation,
the past two decades, uncovering geo-        conducting outreach and teaching pro-
logical secrets from beneath the conti-      grammes and actively cooperating with
nents. It has enabled first-class science    programmes such as IODP. It provides
to be pursued, numerous targets to be        co-funding for coring as well as exper-
probed and hypotheses to be tested,          tise and advice on all matters technical
with the result that fundamental dis-        and logistical. It offers technological
coveries about ‘System Earth’ have been      support for geophysical logging and data
made, often bringing important socio-        management. ICDP is able to mobilise
economic benefits.                           multiple drilling platforms in diverse
UNRAVELLING THE COMPLEXITIES SCIENCE PLAN FOR 2014-2019 SCIENCE PLAN FOR 2014-2019 - GFZ-Potsdam
5 EXECUTIVE SUMMARY
                                                                                                                ICDP

environments: from lake sediment drill-     understanding spatial and temporal
ing for records of climate change over      variability, and the interconnectivity of
the past thousands of years, to special     systems. This is an organisational chal-
technology for drilling into high-tem-      lenge facing all drilling organisations.
perature hydrothermal systems and
micro-sampling for fluids using steri-      The science plan
lised drill-core sampling systems. Public   This document, the third ICDP Science
outreach and teaching are strong com-       Plan, came about by engaging the inter-
ponents of ICDP's profile, and is being     national science community around the         We cordially invite you
expanded further. ICDP is making            theme of ‘Unravelling the workings of         to read this White Paper.
significant difference in educating the     Planet Earth’. It lays out some of the big
                                                                                          You will discover why
public about our subsurface, providing      questions that confront the earth sci-
confidence that we know enough about        ences and suggests ways to answer them
                                                                                          earth science matters,
the upper kilometres in order to provide    that can be achieved by scientific drill-     and uncover the many
resilient solutions to infrastructure and   ing. Some of these questions are funda-       surprising ways in
resource development. A strong edu-         mental, for instance, the origin of life      which it affects your
cation programme will inspire young         on Earth, whereas others use the past
                                                                                          everyday life.
people and help create the next genera-     history of the Earth to imagine what a
tion of scientists who will be needed to    future Earth might look like. Some drill-
specialise in geology, geophysics, geo­     ing applications are highly specialised,
chemistry and geomicrobiology.              such as that for developing sensor net-
                                            works in underground observatories to
Process scales                              monitor earthquakes and volcanoes, the
Scientific drilling must deal with the      latter underpinning geothermal energy
Earth's fundamental processes that          production. To varying extents, these
work on timescales from microseconds,       scientific programmes have objectives
exemplified by stress transfer during       that are shared with the energy, water,
a fault rupturing, to hundreds of mil-      insurance, mining and other industries,
lions of years for plate tectonic cycles.   and with many government objectives,
The same is true of length, breadth and     but ICDP is firmly directed as a research
depth, from sub-micron bio-films and        enabler focused on cutting edge science
mineral defects, to thousands of kilo-      questions and innovations.
metres in fault movements, basin-filling    The main themes in this document are:
and mountain-building processes. The        •  active faults and earthquakes
interconnectivity of processes, including   •  heat and mass transfer
feedbacks, amplifications and degrees       •  global cycles, and
of organisation between them, is stag-      •  the hidden biosphere
geringly complex, involving chemical,       •  cataclysmic events
physical and biological components.         These will underpin societal challenges in:
Scientific drilling has made many fun-      •  water quality and availability
damental discoveries with individu-         •  climate and ecosystem evolution
al drill holes, but the coordination of     •  energy and mineral resources and
targeted activities is a key element in     •  natural hazards.
UNRAVELLING THE COMPLEXITIES SCIENCE PLAN FOR 2014-2019 SCIENCE PLAN FOR 2014-2019 - GFZ-Potsdam
UNRAVELLING THE COMPLEXITIES SCIENCE PLAN FOR 2014-2019 SCIENCE PLAN FOR 2014-2019 - GFZ-Potsdam
7 CONTENTS
                                                                                                                     ICDP

   EXECUTIVE SUMMARY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
   ICDP—WHO WE ARE AND WHAT WE DO . . . . . . . . . . . . . . . . . . . . . . . . . . 8
   QUO VADIS, ICDP ? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
   CONFERENCE ACKNOWLEDGEMENTS . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
   CHALLENGES FOR SCIENCE AND SOCIETY . . . . . . . . . . . . . . . . . . . . . . . 12
   SCIENTIFIC DRILLING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
   MORE THAN SIMPLY DRILLING HOLES—A STRATEGY FOR SUCCESS 16
   PREAMBLE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

PAVING THE WAY FORWARD—THE SCIENCE PLAN

   ACTIVE FAULTS AND EARTHQUAKES . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
   GLOBAL CYCLES AND ENVIRONMENTAL CHANGE . . . . . . . . . . . . . . . 32
   HEAT AND MASS TRANSFER . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
   THE UBIQUITOUS HIDDEN BIOSPHERE . . . . . . . . . . . . . . . . . . . . . . . . . . 56
   CATACLYSMIC EVENTS —IMPACT CRATERS AND PROCESSES . . . . . . 66

   LINKS WITH OTHER ORGANISATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . 74
   ROLE OF INDUSTRY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78
   EDUCATION AND OUTREACH . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80
   EPILOGUE—ICDP IN ACTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86
UNRAVELLING THE COMPLEXITIES SCIENCE PLAN FOR 2014-2019 SCIENCE PLAN FOR 2014-2019 - GFZ-Potsdam
8 ICDP—WHO WE ARE AND WHAT WE DO
                                                                                               ICDP

 ICDP —WHO WE ARE AND WHAT WE DO

Figure 1. ICDP’s commingled funding principle.

Our mission                                      the drilling programme itself, and not
ICDP is the international platform for           for the scientific investigations that fol-
scientific research drilling in continents.      low. Commingled funding is the name
Founded in 1996 at GFZ in Potsdam,               of the game—we encourage and assist
Germany, its mission is to explore the           the scientists in gathering funding, but
Earth’s subsurface so that its structure         do not take on full financial sponsor-
and workings are unfolded.                       ship. A key element provided by ICDP
                                                 in addition to financial support, is oper-
What we provide                                  ational support—the sharing of tech-
ICDP is an infrastructure for scientific         nical and logistical know-how and the
drilling. It provides financial and logis-       provision of operational personnel and
tical assistance for leading international       equipment is critical to scientific drill-
teams of earth scientists to investigate         ing organisations. ICDP is an enabler,
sites of global geological significance.         committed to putting excellent scientific
The financial assistance on offer is for         ideas into best practice.
UNRAVELLING THE COMPLEXITIES SCIENCE PLAN FOR 2014-2019 SCIENCE PLAN FOR 2014-2019 - GFZ-Potsdam
9 ICDP—WHO WE ARE AND WHAT WE DO
                                                                                                                                       ICDP

The base                                     The science plan
ICDP brings together scientists and          ICDP is not a science funding body but
funding agencies from 22 nations             will try to lay out the key research chal-
and one international organisation           lenges in the coming years by commis-
( UNESCO ) to work together at the           sioning a science plan. This plan acts as a
highest scientific and technical level to    roadmap for the international earth sci-
collectively grant funding and imple-        ence community and at the same time
ment logistical support. More than 30        serves as a docking station for national
drilling projects and 75 planning work-      funding initiatives. This White Paper,
shops have been supported to date.           ‘Unravelling the workings of Planet
The programme has an average annual          Earth’, is a strategy document laying
budget of $3.5 million from member-          out the major scientific challenges that
ship contributions.                          may be addressed by continental scien-
                                             tific drilling for the period 2014-2019.
Benefits                                     It is the third for ICDP: the first was
What are the benefits of the programme       published shortly after the foundation of
for its international sponsors? To secure    the program in 1996 by M. D. Zoback           Figure 2. ICDP at the COSC drill site, Sweden.

ICDP funding, all projects must fulfil       and R. Emmermann, entitled ‘Inter-
rigorous selection criteria, one of which    national Continental Scientific Drill-
is addressing modern societal challeng-      ing Program’ and in 2007 the second
es, be it the protection against natural     ‘Continental Scientific Drilling, A dec-
disasters (‘natural hazards’), unravelling   ade of Progress, and Challenges for the
past climate change ( ‘climate and eco-      Future’ by U. Harms, C. Koeberl and
systems’ ), or serving an ever-growing       M. D. Zoback. In parallel to the cur-
population with natural resources ( ‘sus-    rent science plan is a special issue of the
tainable georesources’ ). ICDP projects      International Journal of Earth Sciences
always have this element of added value.     that provides a snapshot of the scien-
                                             tific investigations currently underway
                                             that are directly tied with drilling inves-
                                             tigations.
UNRAVELLING THE COMPLEXITIES SCIENCE PLAN FOR 2014-2019 SCIENCE PLAN FOR 2014-2019 - GFZ-Potsdam
10 QUO VADIS, ICDP ?
                                                                                                ICDP

 QUO VADIS, ICDP ?

Figure 3. On-site participants, ICDP Science Conference 2013

The ICDP science conference ‘Imag-                   The conference’s aim was to debate
ing the Past to Imagine our Future’,                 the way forward for ICDP over the
was convened in Potsdam, Germany,                    next five years. The science plan
11–14 November, 2013. One hundred                    took shape by dovetailing scientific
and sixty-four invited attendees from                goals with societal (socio-economic)
29 countries took part on-site—from                  challenges. The conference was also
early career dynamos to acknowledged                 used to strengthen and expand ties
experts—representing the full palette                among member countries, consider
of earth science disciplines, with many              how to best incorporate industry inter-
more participating via live streaming                ests into ICDP (a science-driven organ-
from the geoscience world at large.                  isation). There also is the objective to
                                                     instigate new measuress for a better
                                                     gender balance in its panels and com-
                                                     mittees.
11 CONFERENCE ACKNOWLEDGEMENTS
                                                                                                                     ICDP

CONFERENCE ACKNOWLEDGEMENTS

Our sincere thanks go out to those who   White Paper contributions
have contributed their valuable time,    Nicholas Arndt,
boundless energy and creative ideas to   Keir Becker,
the conference and the White Paper.      Marco Bohnhoff,
                                         Achim Brauer,
Presenters, discussion leaders           Philippe Claeys,
Flavio Anselmetti,                       Andrew Cohen,
Jean-Philipp Avouac,                     Georg Dresen,
Keir Becker,                             William Ellsworth,
Marco Bohnhoff,                          Guðmundur Ómar Friðleifsson,   Figure 4. Scientists debating at the poster session.

Eduardo de Mulder,                       Ulrich Harms,
Donald Dingwell,                         Brian Horsfield,
William Ellsworth,                       Hans-Wofgang Hubberten,
Guðmundur Ómar Friðleifsson,             Ernst Huenges,
Ulrich Harms,                            Roy Hyndman,
Steve Hickman,                           Jens Kallmeyer,
Brian Horsfield,                         Tom Kieft,
Roy Hyndman,                             Carola Knebel,
Jens Kallmeyer,                          Christian Koeberl,
Tom Kieft,                               Achim Kopf,
Christian Koeberl,                       Ilmo Kukkonen,
Ilmo Kukkonen,                           Ralf Littke,
Steve Larter,                            John Ludden,
Ralf Littke,                             Volker Lüders,
John Ludden,                             Stefan Luthi,
Stefan Luthi,                            Jim Mori,
Jim Mori,                                Karsten Pedersen,
John Shervais,                           Bernhard Prevedel,
Lynn Soreghan,                           Judith Schicks,
Jim Russell,                             Lynn Soreghan,
Alexander van Geen,                      Joanna Thomas,
Jim Whitcomb,                            Robert Trumbull,
Thomas Wiersberg                         Jim Whitcomb,
                                         Thomas Wiersberg,
                                         Maarten de Wit
12 CHALLENGES FOR SCIENCE AND SOCIETY
                                                                                                                     ICDP

 CHALLENGES FOR SCIENCE AND SOCIETY

Integrating the needs of science and         Cycles
society is a cornerstone of the new sci-     Then there is climate change … We            All in all, the workings
ence plan …                                  need to distinguish the change inflict-      of planet Earth are
                                             ed by man, for instance by combusting
                                                                                          far from understood;
The challenge                                fossil fuels, from the natural cycles that
Preparation for and minimising the risk      are part and parcel of Mother Earth.
                                                                                          a great many frontiers
of natural disasters, supplying an ever      Records of what has gone before in           await modern-day
growing world population with indus-         Earth history are preserved in sedimen-      explorers. Scientific
trial raw materials, energy, clean water,    tary rocks at surprisingly high resolu-      drilling provides
and addressing the threats posed by glo-     tion, that help to unravel the puzzle.
                                                                                          key insights into all of
bal change; these are some of the fun-
damental challenges facing mankind in        The origins of life itself and the evolu-
                                                                                          these processes.
the 21st century. All of these challenges    tion of species lie preserved in the sed-
are inextricably linked with the work-       imentary record awaiting discovery.
ings of planet Earth, namely the chemical    Unravelling the links among human
reactions, physical movements and bio-       habitat, climate and palaeogeography is
logical interactions taking place within     already underway.
the solid Earth and at interfaces with the
hydrosphere, atmosphere and biosphere.       The deep biosphere
                                             When we think of life on present-day
Warning and preparation                      Earth, we think of the diversity that is
Events such as earthquakes dramati-          displayed in rain forests and oceans, and
cally impinge upon our lives in seconds,     in the types of micro-organisms (want-
minutes and hours, but the root cause        ed and unwanted) which live in and
is a build-up of stress over thousands       amongst us. Intriguingly, there also is a
of years deep within the crust, often at     biosphere within the pores and cracks of
distant locations. Predicting exactly        rocks (recognised so far to about 2 km)
where and when such natural hazards          that is roughly the same size as the bio-
will occur is a daunting task, but key       sphere we know and love. We are only
advances have already been made by           just beginning to understand how this
monitoring the stress and strain and         deep biosphere is involved in the natural
fluid flow in the Earth’s subsurface using   cycling of elements, and exploring the
sensitive instrumentation, and by issu-      ways in which we can understand and
ing early warnings via integrated earth      put this underground system to good
science infrastructure.                      use.
THE EARTH BENEATH OUR FEET—
 THE DARK UNDERGROUND

Brian Horsfield   GFZ— German Research Centre for Geosciences, Germany

We think we know our planet, the                      underworld and to verify our models        ‘We want to bring
Earth. Detailed maps, aerial pictures                 of Earth is to recover samples from         scientific drilling on
and satellite images give us the im-                  depths and to obtain data in the dyna­
                                                                                                  continents within
pression —albeit false —that no place                 mic downs.
on our planet remains unexplored.
                                                                                                  the reach of every
But who knows what it is like within                  Drilling is an expensive proposition        member of the earth
the earth beneath our feet and how                    that rarely a single country can afford     science community.’
can we gain information about this?                   due to the enormous costs associated
                                                      with the logistics. How can researchers
Geologists study every road cut,                      justify such costs to a funding agency,
where machines and dynamite have                      if the results are merely scientific and
exposed the layers of rock normally                   do not gush out a wealth of resources?
hidden beneath soil and vegetation.                   This is exactly where ICDP comes
Geophysicists use seismic rays and                    in. The goal of this programme is to
electromagnetic waves to figuratively                 encourage earth scientists considering
peel away the layers of the earth.                    drilling as a tool for their research
Geochemists study the rocks which                     and to make drilling the reality check
they believe were once part of the                    for the models and ideas developed.
interior of the earth. But the plethora
of information gathered by all these                  The scientific focus of ICDP for the
means leads at best to models and                     forthcoming years is laid out in this
hypotheses about the Earth’s interior.                White Paper to serve as a guideline for
The best way to enlighten the obscure                 continental scientific drilling.

Figure 5. 3 D structural model of the Central European Basin System.
14 SCIENTIFIC DRILLING
                                                                                        ICDP

 SCIENTIFIC DRILLING

Figure 6. The build-up of stress.

Scientific drilling is an indispensa-      ICDP is not alone in conducting sci-
ble and unique tool for exploring and      entific drilling on a global scale. We are
unraveling the myriad natural and          building stronger links between the ter-
anthropogenic processes that are part      restrial ( ICDP ) and marine ( IODP )
and parcel of ‘System Earth’. The pre-     realms for the development of con-
cious relicts and living systems it con-   certed actions, extending from involve-
tains need to be probed, collected, mon-   ment in respective science plan defini-
itored and analysed at key sites around    tion, through individual project design,
the globe.                                 to the joint publication of the magazine
15
   SCIENTIFIC DRILLING                                                                                        ICDP

Scientific Drilling. There are further
links with ANDRILL, whose focus is
the Antarctic, and the Deep Carbon
Observatory, which studies the deep
carbon cycle, are also under develop-
ment. The pooling and coordinating
of our respective actions, whether
it be on land, sea or ice, is impera-
tive. The White Paper revisits these
issues.

Scientific drilling has objectives that
are broadly shared with the oil and        Figure 7. Drill bits at the Alpine Fault drill site, New Zealand

gas, water, insurance, mining and oth-
er industries. All are seeking to better
understand the workings of ‘System
Earth’. In the commercial world the
objectives are to secure new resources,
exploit known ones, and minimise risk
associated with natural hazards and
resource development. Scientific drill-
ing remains science-driven, seeking to
understand the chemistry, physics and
biology in time-space coordinates. It
makes sense to explore areas of com-
mon interest with industry, for exam-
ple selected data and sample acquisi-
tion. When managed astutely, pure
and applied research go hand in hand
to achieve common objectives. The
White Paper considers these issues.
16 MORE THAN SIMPLY DRILLING HOLES—A STRATEGY FOR SUCCESS
                                                                                          ICDP

 MORE THAN SIMPLY DRILLING HOLES
 —A STRATEGY FOR SUCCESS

Scientific drilling relies heavily on lead-   •  Provide operational support for
ing edge technology. But it is way more         drilling activities, downhole logging
than that. The ICDP portfolio covers            tools, and sample- and data-
finances, logistics and operational sup-        management software systems.
port, and all with minimal administra-        •  To ensure appropriate monitoring
tive and bureaucratic fuss. Here is a           of the programme and accountability
list of tasks and challenges that are part      to sponsors in terms of scientific
and parcel of that portfolio:                   effectiveness and financial efficiency;
•  Identify world class drilling             •  Ensure effective application
  sites to probe geological targets             and dissemination of the results. Also
  of global significance.                       to inspire young scientists. ICDP
•  Fund workshops to assemble the best         makes substantial effort to encourage
  science teams, define scientific              earth science education and facilitate
  objectives and mesh scientific ideas          knowledge transfer.
  with practical drilling concepts.
•  Provide accountability for sponsors       We are striving to improve upon the
  for the programme as a whole,               way we do business by ensuring that
  in terms of scientific effectiveness        each task is conducted efficiently and
  and financial efficiency.                   effectively. The closing chapter of
•  Arrange commingled funding                this White Paper looks into how the
  concepts for the effective planning,        organisation can be managed better.
  implementation and execution of
  a viable strategic programme
  which meets scientific objectives of
  socio-economic relevance.
•  Identify sites for international
  cooperation in scientific drilling, and
  thus to provide cost effective means
  of answering key scientific questions,
  in close collaboration with other
  scientific drilling organisations.
•  Ensure that appropriate pre-site
  surveys are carried out at an early
  stage in planning, including required
  permits, environmental and local
  social issues.
17                                                                                                                                        ICDP

                Modern technology for scientific drilling:
                the basic elements

                     Geophysical pre-site surveys are needed to map out the lay
                     of the land. This means accurate target definition as well as
                     avoiding potential drilling hazards such as unstable rock
                     formations.

                     Blowout preventers are used to control the fluid and gas
                     pressure inside the well. They consist of several valves to
                     close the well if overpressure occurs.

                     Steel casing, cemented into place, is used to seal the
                     borehole along its length. Large diameters are used at
                     shallow depths, and succeeded by casing of progressively
                     lower diameter at depth. That way unstable zones can be
                     stabilised and different fluid horizons can be isolated
                     (e.g. groundwater from salt water).

                     Active control systems behind the bit help to ensure
                     exact vertical drilling. Thereby friction between the drill
                     string and the borehole wall can be minimised and the
                     borehole wall stays stable.

                     The drilling mud serves many purposes. It discharges
                     cuttings from the bit to the surface and stabilises the bore-
                     hole. It also constantly cools the drill bit, reduces friction,      Cement
                     drives the downhole motor, and balances differences in
                     pressure. The drilling mud must therefore be monitored and
                     its chemistry and rheology adjusted continuously.

                     Borehole measurements and tests help to characterise
                     rocks and, fluids, thereby maximising safety.                     ICDP projects address a whole host of geologi-
                                                                                       cal targets from deep to shallow, from tectoni-
                                                                                       cally simple to complex, and under very diffe-
                                                                                       rent pressure and temperature conditions.
                     Controlled drilled horizontal wells with up to 10 km of
                     deviation and multiple re-entry protocols allow access to
                                                                                       Modern technology ensures all these targets
                     distant formations. When drilled along the bedding of a           can be reached, even if they lie at 12 km depth!
                     formation, gas and crude oil production efficiency is
                     enhanced.                                                         Having said that, costs rise exponentially with
                                                                                       depth and degrees of difficulty, so detailed and
                                                                                       careful planning is prerequisite.

Figure 8. Drilling scheme
18 THE SCIENCE PLAN—PREAMBLE
                                                                                                                 ICDP

 THE SCIENCE PLAN — PREAMBLE

Maarten de Wit Africa Earth Observatory Network, Nelson Mandela Metropolitan University, Port Elizabeth, South Africa

Earth processes proceed at variable         of Earth and life systems: the connectiv-    Unearthing palaeo-
speeds, from steady and slow, to fast,      ity between black smokers and ecosys-        complexity through con-
sometimes showing gradual change,           tems; or that of global changes emerg-
                                                                                         tinental scientific drilling
sometimes sudden, and sometimes             ing out of the atmospheric ‘symphony’
impinging catastrophically on ecosys-       of fluctuating palaeotemperatures and
                                                                                         for the benefit of
tems. In rock systems these changes         palaeo-gas concentrations, as recorded       future generations.
are recorded as stratigraphical inter-      in ice cores. These, and similar discov-
ference patterns that geoscientists con-    eries forced a relatively rapid shift in
vert with ever-greater precision into a     focus from closed-system solid-Earth
narrative full of complexity and sur-       geodynamics to its symgeosis with the
prises. We do not fully comprehend          external gas–fluid envelope, the exo-
the system (Ager, 1973; Rudwick, 2005;      sphere. The solid Earth’s ‘leaky’ systems,
Blackburn et al., 2013), but progress       each evolve whilst interacting with each
has been made: geoscience has self-         other, recycling through non-linear,
organised into earth systems science        positive and negative, slow and fast,
enabling more complex questions to be       feedback reactions forced by seemingly
addressed about systemic interdepend-       unpredictable fluctuations in energy
encies and connectivity of palaeo-proc-     and mass exchange. But, this ubiquitous
esses; about how oceans that opened         connectivity is poorly understood.
and closed affected palaeo-global cur-
rents, climates, weathering, seawater       Complex systems are comprised of
chemistry, and biodiversity. And when       many interactive parts with the abil-
it became clear that such hyperconnec-      ity to generate a new quality of collec-
tivity is vulnerable to failure through     tive behaviour through self-organisa-
rapid external forces, such as extrater-    tion (Prigogine, 1984; Odem, 1988; Bak,
restrial impacts or large mantle plumes,    1996; Camazine et al., 2001; Ben-Jacobs,
earth systems science suddenly stumbled     2002). Petrologists have long docu-
into a new era of exploring Earth as a      mented evolving patterns and phase
complex interactive adaptive system.        changes (solid–liquid–gas as a function
                                            of pressure, temperature and composi-
Fundamental insights into how the           tion) in mineral and rock systems at the
Earth functions as a complex auto-          edge of chaos (fluids). At such special
catalytic and adaptive system emerged       phase boundaries self-organisation is
at the end of the 20th and early in         spontaneously constituted, and further
the 21st century, following exciting evi-   complexity evolves through dissipative
dence, for example, of the co-evolution     processes. Scale-invariant earth systems
19 THE SCIENCE PLAN—PREAMBLE
                                                                                           ICDP

Figure 9. Complexity word cloud

somehow all appear to acquire the abil-       maintains homeostasis through cause
ity to hover between order and cha-           and effect (Lovelock, 1972). Which sys-
os. Ongoing ICDP projects which are           tem dominates the Earth is still open to
looking into the supercritical zones of       debate, but can be tested with new high-
hydrothermal and magmatic complexes           resolution data and disruptive thinking.
are already providing new and needy
observational data to test for conditions     Increasingly, ecosystem studies have
of instability at mantle scales. Similarly,   generated concepts that may apply to
fast response drilling into fault zones       all complex systems when appropriately
can test for critical states in the crust.    generalised with network models, ener-
                                              gy, and information. High-fidelity strati-
Self-organisation in natural systems          graphical studies may recognise such
emerges from a dynamic hierarchy of           signals in geosystems too. The ICDP
information. Self-organisation of earth       community and their IODP colleagues
systems reconnects its parts and proc-        have unique opportunities to core dis-
esses into new operating cycles through       parate archives that overlap in time and
evolving information between core,            space to search for palaeo-connectivity
mantle, crust, air, oceans, and life. No      between earth systems, to reconstruct a
model can yet account holistically for        palaeo-interconnected world, and tease-
such dynamic connectivity within natu-        out local and global adaptive behaviour
ral information systems (Toniazzo et al.,     of the past. Bringing together the obser-
2005). Some argue that the basis for this     vations from time-overlapping cores
is simply rooted in the second law of ther-   retrieved from lakes, ice, speleothems,
modynamics to maximise entropy pro-           rocks and minerals, will lead to better
duction unbeholding to cause and effect.      understanding of palaeo-adaptive sys-
Systems dissipate and reorganise, driven      tems over deep time and add immense
by simultaneous interactivity far from        value to drilling projects.
equilibrium (Kleidon and Lorenz, 2005).
Others entertain the view that the entire     The ability to compare overlapping
planet is a self-organising system that       sequences across the planet, at selected
20 THE SCIENCE PLAN—PREAMBLE
                                                                                                                                                                                                                                                                                                                                                                      ICDP

                                                                                            8                                                                                                           44                                                                                                  26
                                                                                                                                                                                            37
                                                  3                                                                                                                                                                                                                                                                                                               26
                                                            43        26                                                                                    31                               7 54                     23
                                                                             14                                                      14                                24
                                                                                                                                                                                       12
                                                                                                                                                                                                  10
                                                                                                                                                             42             18       35                 49                                      23                                   2
                                                                                                                                                                                            17
                                                                                            39                                                                         33                                                                                                                                                                              46
                                                                       32     22       17                                                                                                              51                                                                                                   57
                                                                  27                                                                                                              20                                                                   33                  13
                                                              43       9            36 30                                                                                        4 45 58                                                                                                      3                                 34
                                                                            15                                                                                                   28                                     52
                                                                                                                                                                                                             25
                                                             27
                                                                        18
                                                                           49    28       48
                                                                                                                                                                        31
                                                                                                                                                                                 3
                                                                                                                                                                                                                                                                37              40                 9 29 66 5
                                                             6                          34                                                                                       10 12 19
                                                                            23                                                                                                                                                                                                                                                       35
                                                                42 4 10        11 19 8                                                                                     16 27          24
                                                             56                                                                                             46                                                                        50                                             16                                    47
                                      38                        20       7                                                                                                                                       21
                                                                                 14
                                            28                                                                                                                                                                                                         9                                      17 63              11
                                                                                            4                                                                                                                                                                                   32
                                                                                   7 55               24                                                                                                              25 3
                                                                                                                       47
                                                                                            8                                         44                                                                               30
                                                                                                         5                                                                       3                          29                                                                                         65
                                                                                                                                           21
                                                                                                                                                                                                                        16
                                                                                                                                                                                                      62
                                                                                                                            2                                                                                            15                                                                                                 5
                                                                                                 36                                                                                                   21 64
                                                                                                                                                                                                                                                                                                                                                             48
                                                                                                         41                                                                                                      39                                                                                1
                                                                                                                                                                                                        6                                  40
                                                                                                                  2                             38
                                                                                                                                                                                                                 1
                                                                                                                                                                                                       15                                                                                11                                                                            25
                                                                                                                                 13
                                                                                                                                                                                                                                                                                                                                                                             45
                                                                                                                       20                                                                                                                                                                                                                                   18
                                                                                                                                                                                                                                                                                                                                                                  30
                                                                                                             53
                                                                                                                                61

                                                                                                                                                                                                                                                                                                                                                            22
                                                                                            12                                                                                                                                                                                                                                                                           6

                                                                                                                                                                                                                                                                                                                                                                             24
                         14                                                                                       16                                                                   10                                        18                                  7                                                    9, 11                         4             10
                                                                                                    17                                                                                 19                                       20                                          8, 15                                      26, 29                                          1, 3, 5, 6
 New proposals

                                                                                                                                                                                                 23                                                                                                                                  2
                                                                                                                                                                                                                                                                                                                                              13,21
                                                                                                                                                                                                                                                                                                                           12                                          22
                                                                                                                                                                                                                                                                                                             30                                                       25
                                                                                                                                                                                                                                                                                                                                                                       27, 28

                                                                                                                                                                                                                                                                 3, 12, 13, 17, 20, 24, 25, 26, 29, 37, 38, 40, 42, 43, 45, 47, 48
                                                                                                                                                                                                                                                                                                             18
                                                                                                                                                                                                                                                                                                                                         46
                                1                                                               7                                                                           28                                                                                            9, 10, 36                                         14                              27
                                             11                                                                                                                                                                                  19                                                                                                                 16, 31                   2, 30
                                            15, 39                                                                                                                                                                                                                                                22                                                                    8
 Submitted proposals

                                                       23                                                                                                                                                                             33                                                                              49                                    5, 35
                                                                                                                                                                                                                                                                                                                                         4, 6, 41, 44
                                                                                                                                                                                                                                                                                                        34                                                                32
                                                                                                                                                                                                                                                                                                                      21

                                                                                                                                                                                                                                2, 3, 4, 5, 7, 10, 11, 16, 18, 20, 22, 24, 25, 28, 32, 34, 36, 38, 41, 42, 47, 52, 54, 58, 65, 66
                              1, 15                                                                                    12                                                                                                             13                                                                                    8
                                           6, 23, 60                                                                                                                                                                                                                                                                       37                                     26, 40
                                              9                                                                                                                                                                                                                                                                                               17, 35
                                                             22, 49                                                                                                                                                                                                          50                                                          43                      19
                                                                                                                                                                                                                                                                44                                                                                      33, 21
 Completed and ongoing

                                                                                                                                                                                                                                                                                                  61                                                              27, 29
                                                                                                                                                                                                                                                                            31, 51, 57
                                                                                                                                                                                                                                                45
                                                                                                                                                                                                                                                                                                                                                        48
                                                                                                                                                                                                                                                                                                                  56, 14
                                                                                                                                                                                                       59
                                                                                                                                                                                                                                                                                                                                                       63
                                                                                                                                                                                                                                                                                                                                         64

                                                                                                                                                                                                                                                                                                                                          30, 39, 46, 53, 55, 62

                                 precambrian                                                                                                                                                 phanerozoic
                                                                                                                                 Paleozoic                                                                                                      Mesozoic                                                                         Cenozoic
            Archean Proterozoic
                                                                            Cambrian            Ordovician              Silurian                 Devonian         Carboniferous             Permian                  Triassic               Jurassic                     Cretaceous                               Paleogene                        Neogene                  Q
          4000                         2500                      541                      485                      443                    419                    359                 299                    252                  201                    ~ 145                                               66                                23                  2.5           0

Figure 10. Decadal map of ICDP drill sites ( 2004–2014 ) showing locations of completed, planned and proposed continental drilling projects, together with their
projected archival time-spans. Numbers along the chronostratigraphical timescale are in millions of years; note that out of a 145 sites, 52% of planned cores
overlap within the most recent 2.6 million years [ Quaternary ( P=Pleistocene; H=Holocene ) ]; whilst 4% overlap within the earliest 1500 million years of earth
history for which there is a preserved rock record ( modified from Soreghan and Cohen, 2013 ).
21
   THE SCIENCE PLAN—PREAMBLE                                                              ICDP

lines of longitude across the equator to      thinking to bridge the gap between the
the poles provides tests for global chang-    earth and social-system sciences.
es. It can provide estimates of the ampli-
fication of system sensitivity caused by      Today’s strongly connected global proc-
positive feedbacks, to develop a general      ess networks are highly interdepen­
set of algorithmic approaches for quanti-     dent systems that we do not understand
fying the way complex adaptive systems        well (Helbing, 2013). These systems are
interact with one another, and how they       vulnerable to failure and can become
get connected through nature’s incessant      unstable at all scales even when external
compulsion for self-organisation into         shocks are absent. As the complexity of
evolving patterns. In deeper time too,        interactions in global networked palaeo-
overlapping sequences from ancient cra-       systems becomes better understood, we
tons will likely link high-fidelity fluctu-   may develop technologies to make the
ations in biogeochemistry systems and         anthropogenic systems manageable so
early life.                                   that fundamental redesign for future
                                              systems may become a reality.
Understanding how complex self-orga-
nising systems respond to external            We are at the threshold of new transdis-
forcing is important, especially the          ciplinary thinking about earth system
emergence of feedbacks sometimes              complexity, and there will be a long list
passing ‘points of no return’ without         of relevant questions that we must ask
warning before approaching tipping            of the cores from drilling programmes.
points (‘catastrophic bifurcations’).There    Inspection of the spatial and tempo-
are now signs that tipping points can         ral distribution of ICDP ’s archived and
be predicted when critical thresholds         anticipated drill-core (Figure 10) pro-
are approaching, spatially as well as         vides powerful argument for construc-
temporally (Rietker et al., 2004; Scheffer    tive engagement and efficient design
et al., 2009; Carpenter et al., 2011;         of time-overlapping coring across the
Carpenter, 2013; Dai et al., 2013).           globe through collaborative drilling
                                              projects to chart the connectomics of
With more deep-spatial and deep-time          our planet from core to space; and from
data it may become possible then to           the past into the future.
make more robust predictions about a
future Earth to strengthen cohesion with      Acknowledgements
socio-economic and political systems,
and to develop a greater planetary cul-       I have benefited greatly from 10 years
ture to combat looming crisis (Morin          interactive discourse on the ICDP Sci-
and Kern, 1999; Hansen et al., 2013).         ence Advisory Group, under the leader-
New endeavours like earth stewardship         ship of Stephen Hickman, who can create
science can collate the required criti-       order out of any chaos. I am grateful to
cal knowledge to stimulate self-organ-        ICDP for their facilitating role and gen-
ised paradigm shifts in transdisciplinary     erous funding and to Bastien Linol for
                                              help with Figure 10.
22 THE SCIENCE PLAN—PREAMBLE
                                                                                                                                         ICDP

   References
Ager, D. V.: The Nature of the Stratigraphical Record,                   Soreghan, G. S. and Cohen, A. S.: Scientific drilling and the
      Halsted (Wiley), New York, 114 pp. (3rd edition 1992,                    evolution of the earth system: climate, biota, biogeo-
      151 pp.), 1973.                                                          chemistry and extreme systems, Scientific Drilling 16,
Bak, P.: How Nature Works: The Science of Self-Organised                       63–72, doi:10.5194/sd-16-63-2013, 2013.
      Criticality, New York, Copernicus, 1996.                           Toniazzo, T., Lenton, T. M., Cox, P. M., Gregory, J.: Entropy
Ben-Jacobs, E.: When order comes naturally, Nature, 415, 370,                  and Gaia: is there a link between MEP and self-
      doi: 10.1038/415370a, 2002.                                              regulation in the climate system? In: Non-equilibrium
Blackburn, T. J., Olsen, P. E., Bowring, S. A., McLean, N. M.,                 thermodynamics and the production of Enthropy
      Kent, D. V., Puffer, J., McHone, G., Rasbury, E. T.,                     (Eds. Kleidon, A. and Lorenz, R. D.), Springer, Berlin,
      Mohammed Et-Touhami, T. M.: Zircon U-Pb Geo-                             223 –241, 2005.
      chronology Links the End-Triassic Extinction with the
      Central Atlantic Magmatic Province, Science, 340,
      941–945, 2013.
Camazine, S., Deneubourg, J.-L., Franks, N. R., Sneyd, J.,
      Theraulaz, G., Bonabeau, E.: Self-Organisation
      in Biological Systems, Princeton University Press,
      538 pp., 2001.
Carpenter, S. R.: Complex systems: Spatial signatures
      of resilience, Nature 496, 308–309,
      doi:10.1038/nature12092, 2013.
Carpenter, S. R., Cole, J. J., Pace, M. L., Batt, R., Brock, W. A.,
      Cline, T., Coloso, J., Hodgson, J. R., Kitchell, J. F., Seekell,
      D. A., Smith, L., Weidel, B.: Early Warnings of Regime
      Shifts: A Whole-Ecosystem Experiment, Science, 322,
      1079–1082, doi: 10.1126/science.1203672, 2011.
Dai, L., Korolev, K. S., Gore, J.: Slower recovery in space
      before collapse of connected populations, Nature 496,
      355–358, doi: 10.1038/nature12071, 2013.
Hansen, J. et al.: Assessing “Dangerous Climate Change”:
      Required Reduction of Carbon Emissions to Protect
      Young People, Future Generations and Nature, PLOS
      One 8, 12, 1–26, doi:10.1371/journal.pone.0081648,
      2013.
Helbing, D.: Globally networked risks and how to respond,
      Nature 497, 51–59, doi:10.1038/nature12047, 2013.
Kleidon, A., Lorenz, R. D.: Non-equilibrium thermodynamics
      and the production of entropy: Life, Earth, And Beyond
      (understanding Complex Systems), Springer, Berlin,
      260 pp., 2005.
Lovelock, J.E.: Gaia as seen through the atmosphere,
      Atmospheric Environment Vol. 6, Pergamon Press,
      579-580, 1972.
Morin, E. and Kern, A. B.: Homeland Earth: a Manifesto
      for the new Millenium. Advances in system theory,
      complexity and the human sciences, Hampton Press,
      Inc. NJ., 153 pp., 1999.
Odem, H. T.: Self-Organisation, Transformity and Informa-
      tion, Science 242, 1132–1139, 1988.
Prigogine, I.: Order out of Chaos, Toronto, Bantam Books,
      1984.
Rietkerk, M., Dekker, S. C., de Ruiter, P. C., van de Koppel, J.:
      Self-Organised Patchiness and Catastrophic Shifts in
      Ecosystems, Science 305, 1926–1929, 2004.
Rudwick, M. J. S.: Bursting the Limits of Time—The recon-
      struction of Geohistory in the Age of Revolution,
      The University of Chicago Press, Chicago and London,
      708 pp., 2005.
Scheffer, M., Bascompte, J., Brock, W. A., Brovkin, V.,
      Carpenter, S. R., Dakos, V., Held, H., van Nes,
      E. H., Rietkerk, M., Sugihara, G.: Early-warning signals
      for critical transitions, Nature 461, 53–59, 2009.
PAVING THE WAY FORWARD —THE SCIENCE PLAN
ACTIVE FAULTS AND EARTHQUAKES

GLOBAL CYCLES AND ENVIRONMENTAL CHANGE

HEAT AND MASS TRANSFER

THE UBIQUITOUS HIDDEN BIOSPHERE

CATACLYSMIC EVENTS —IMPACT CRATERS AND PROCESSES
24 SCIENCE PLAN ELEMENTS
                                                                                                          ICDP

 ACTIVE FAULTS AND EARTHQUAKES

Jim Mori  Disaster Prevention Research Institute, Kyoto University, Kyoto, Japan
William Ellsworth  U.S. Geological Survey, Menlo Park, USA

Figure 11. An automobile crushed under the third story of an apartment building in the Marina District,
San Francisco — the Loma Prieta earthquake in 1989, magnitude 6,9

Lay of the land                                       takes time and is an ongoing endeav-
                                                      our. However, contributions to scien-
A single earthquake and associated tsu-               tific knowledge, as described in the fol-
nami in a populated region can kill tens              lowing sections, address critical issues
of thousands of people and cause huge                 such as establishing occurrence rates of
economic losses that are a significant                severe events and evaluating the inten-
percentage of the GDP of the strick-                  sity of the damaging ground shaking as
en country. The developing countries                  needed for seismic zoning and emer-
(the 2010 M7.0 Haiti earthquake killed                gency measures planning. Also, drill-
over 100,000 people) and technologi-                  ing projects draw public attention to the
cally advanced countries (the M9.0 2011               seismic hazards of a region and can be
Tohoku earthquake in Japan caused sev-                the catalyst for effective education and
eral hundred billion dollars of damage)               outreach efforts.
are all prone to these disasters. A few
research boreholes drilled into active                Earth tremors and earthquakes can be
faults and equipped with monitoring                   induced; with the increasing production
tools is not going to immediately reduce              of shale gas and shale oil, the building
the damage from earthquakes; this                     of reservoirs for hydroelectricity, and
25 SCIENCE PLAN ELEMENTS  / ACTIVE FAULTS AND EARTHQUAKES
                                                                                                                                          ICDP

the pumping of fluids into underground          We have begun to answer some of the
storage areas, it is clear that the last dec-   key questions raised 20 years ago when
ade has seen a dramatic increase in the         the first boreholes into fault zones were
earthquakes associated with human               being planned, and significant progress
activities (e.g. Gupta, 2002; Ellsworth,        has been made in answering these ques-
2013). A better understanding of condi-         tions.
tions and mechanisms of these seismic           • Why are major plate-boundary
events should lead to better-informed              faults like the San Andreas Fault weak?
policies for the regulation and operation       • How do stress orientations and
of a number of human activities.                   magnitudes vary across the fault zone?
                                                • What are the width and structure
Past accomplishments in ICDP                       (geological and thermal) of the princi-
                                                   pal slip surface(s) at depth?
During the last two decades, deep bore-         • What are the mineralogies, defor-
hole drilling into fault zones has opened          mation mechanisms and frictional
new fields of research for a better                properties of the fault rocks?
understanding of earthquake process-            • How is energy partitioned within
es. Land-based drilling projects on the            the fault zone between seismic
Nojma Fault Japan, (Ando et al., 2001),            radiation, frictional heating, commi-
San Andreas Fault, USA (Zoback et al.,             nution and other processes?
2011), Chelungpu Fault, Taiwan, (Ma et
al., 2006), Wenchuan Earthquake Fault,          Fundamental open questions
(China, Li et al., 2012), Gulf of Corinth,
Greece (Cornet et al., 2004), and Alpine        In the next decade, future fault zone        Figure 12. The complexity of real fault zones.

Fault, New Zealand, (Toy et al., 2013a)         projects will continue to improve our
along with ocean drilling in subduc-            understanding of the structure and
tion zones of the Nankai Trough (Tob-           processes of active faults which result in
in et al., 2009), Japan Trench (Chester         large earthquakes, by focusing on these
et al., 2013), and Costa Rica (Vannuc-          issues:
chi et al., 2013), have obtained valuable       • How do earthquakes nucleate?
samples and measurements from active            • How do they propagate?
fault zones from depths reaching several        • Why do they stop?
kilometres. We have obtained a much             • What controls the levels of ground
better knowledge of the physical prop-             motion during earthquakes?
erties of active fault zones that produce       • What controls the frequency and
large damaging earthquakes. An impor-              size of earthquakes
tant result is recognition of the immense       • How is fluid involved and how
complexity observed in the fault zone              does fault permeability vary during
rocks, including their varied structur-            earthquakes?
al and chemical characteristics, along          • How does stress magnitude
with the associated fluid properties               and orientation vary during the
(Figure 12).                                       earthquake cycle?
26 SCIENCE PLAN ELEMENTS  / ACTIVE FAULTS AND EARTHQUAKES
                                                                                                                                       ICDP

Future scientific targets                     structure of fault zones, flow paths of
                                             fluids and the role chemical reactions of
From discussion at the 2013 ICDP             introduced waters play in modifying the
Science Meeting, we have identified          permeability structure. Permeabilities
research areas that can be advanced          can vary by orders of magnitude across
through drilling projects and have the       varying geological structures and have
potential for producing critical new         a strong effect on the frictional proper-
results for understanding earthquakes.       ties of the fault during large earthquakes
                                             (e.g. Tanikawa et al., 2013). Borehole        Figure 13. Start of drilling at the GONAF location
                                                                                           in Tuzla, Turkey
Induced earthquakes                          studies of the fluid-flow and pressure
It has been recently recognised that an      transmission regimes may thus produce
increasing number of earthquakes are         important results.
associated with human activities such
as reservoir filling, mining, waste-water    Borehole observatories
injections, and CO2 sequestration.           The last decade has seen a rapid increase
Induced earthquakes of small to moder-       in the development and installation of
ate size have caused damage throughout       borehole instrumentation on the San
the world (e.g. 1967 Koyna, India; 2011      Andreas Fault (Zoback et al., 2011),
Oklahoma; 2006 Basel, Switzerland). In       Chelungpu Fault (Ma et al., 2012), North
many of the documented cases in the lit-     Anatolian Fault (Bohnhoff, 2013), and
erature, variations in pore fluid pressure   at various other locations around the
are implicated as the primary physical       world (Figure 16). These instruments
mechanism that triggers earthquakes          record a variety of types of data such
(e.g. Gupta, 2002; Deichmann and Gia-        as seismic waves, deformation and
rdini, 2009; Ellsworth, 2013). Major         tilt, temperature, and fluid pressure.
questions remain about how fluid pres-       Boreholes provide unique access into
sure migrates through the Earth, and         the nearfield region of the earthquake
how ancient faults can be reactivated        source and provide extremely low noise
by this mechanism. Resolution of these       conditions for observing the system,
and other questions requires in-situ         which is not attainable at the Earth’s sur-
observations in boreholes in the source      face. ICDP can play an important role
regions of these earthquakes. ICDP can       in coordination of instrument develop-
play an important role in investigating      ment among different groups and sup-
the physical and chemical processes and      port for deployment at important sites
evaluating hazard implications of such       on active seismic regions.
human-induced seismic events.
                                             For example, little is known about the
Role of fluids                               source mechanisms of low-frequency
The importance of the effects of water       earthquakes that may occur in more
for both natural and induced earth-          ductile regions of the crust. Borehole
quakes has long been appreciated.            observations of these and other types of
However there is currently only limit-       seismic and deformation events can lead
ed information about the permeability        to a better understanding of the wide
27                                                                                                                            ICDP

 DOWNHOLE EARTH OBSERVATORY
Marco Bohnhoff, Georg Dresen  GFZ— German Research Centre for Geosciences, Germany

High-resolution downhole                        research for decades, demonstrating       band as well as GPS and strain meter
seismic monitoring                              that the effort needed for implement-     measurements. Microseismicity will
In order to perform high-resolution             ing permanent downhole monitoring         be monitored at low magnitude-detec-
seismic monitoring of critical faults           systems pays off on the long term.        tion threshold and with high precision
overdue to generate large earth-                                                          not achievable with surface record-
quakes, it is necessary to place                The ICDP-GONAF project                    ings. Using the downhole observa-
geophones in low-noise environments             The North Anatolian Fault Zone in         tions, the driving physical processes
and as close as possible to the fault           Turkey has produced several large         along a transform fault segment,
zone. Such conditions can be met only           (M>7) earthquakes in the historic past    which is in the final state of its seismic
by drilling boreholes located close to          leaving the Marmara Sea segment           cycle, will be studied prior, during
the target fault. Beginning in the late         as the only part of the entire fault      and after a large (M 7+) earthquake.
80s in the USA and Japan, borehole              zone that has not generated a major       Furthermore, the role of structural
installations have been successfully            earthquake since 1766. Currently,         heterogeneities of the NAFZ below
operated throughout the last decades.           there is a high probability for a major   the Sea of Marmara will be investi-
Much experience has been gained                 earthquake less than 20 km from the       gated for slip distribution, nucleation
from these efforts, in particular from          roughly 13 million people who live        process, and magnitude of the pend-
the local high-resolution seismic               in Istanbul. In order to monitor this     ing Marmara earthquake.
network ( HRSN ) on the San Andreas             critical part of the fault, a borehole
Fault in California and the Hi-net in           Geophysical Observatory at the North      Drilling holes is more than just
Japan. Such installations are still rare        Anatolian Fault zone ( ICDP-GONAF         collecting samples. Installation of sen-
but have produced unique earth-                 project) has been initiated. GONAF        sitive instruments in boreholes allows
quake waveform recordings, provid-              is a joint research venture between       us to directly access the underground
ing state-of-the-art seismological              GFZ Potsdam and the Turkish Disaster      where earthquakes nucleate. This
                                                and Emergency Presidency ( AFAD )         is the key for near-source earthquake
                                                in Ankara. When completed, it will        monitoring providing the base for im-
                                                comprise an eight-station earthquake      proved seismic risk and also resource
                                                downhole observatory, each equipped       management.
                                                with vertical arrays of seismometers
                                                in 300 m deep boreholes on the main-
                                                land and on the Princes Islands being
                                                located within 3 km to the fault.

                                                Key challenges
                                                The principal objectives of the
                                                GONAF project are to monitor micro-
                                                seismic activity and deformation proc-
                                                esses in the broader Istanbul region
                                                using downhole seismic observations
                                                over the entire seismic frequency
Figure 14. Recordings of the Tuzla earthquake
swarm of 2013
28 SCIENCE PLAN ELEMENTS   / ACTIVE FAULTS AND EARTHQUAKES
                                                                                                                                         ICDP

range of physical mechanisms for strain       Deep mines also provide a natural labo-
accumulation and release in the crust.        ratory for studying failure mechanisms.
                                              They provide straightforward access to
Experiments on core material                  the locus of deformation induced by
and modeling                                  mining and can be extensively instru-
Laboratory analysis of rock, fluid and        mented with seismic and deformation
gas samples from active faults obtained       instrumentation in the extreme near-
from depth provide important infor-           field of the process, such as in the South
mation on the physical and chemical           African goldmines (e.g. Ogasawara et al.,     Figure 15. Affected dam after the Jiji earthquake
                                                                                            in 1999, Taiwan
properties of fault deformation mech-         2013).
anisms. These mechanisms span the
range from continuous creep to sudden         Another potential experiment uses
slip in earthquakes (e.g. Ikari, 2013). The   injection of water into a fault zone to
rate dependence of friction and tempo-        produce small earthquakes. An experi-
ral evolution of fault-zone permeabil-        ment of this type was done at Rangely,
ity are just two of the important para-       Colorado, USA more than 40 years ago
metres that can only be obtained from         when an array of boreholes into a fault
direct sampling of faults in-situ. Under-     zone were used to modulate the rate of
standing of the physical and chemical         earthquakes (Raleigh et al., 1976). This
processes that lead to the development        experiment verified the effective stress
of the fault core where the great major-      mechanism for triggering earthquakes
ity of the sliding occurs and surrounding     by modulating the pore fluid pressure
damage zone requires the retrieval of a       inside the fault. Today, critical questions
broad suite of samples of fault rocks and     remain about the feedback between fault
fluids. Such physical data is especially      movement and the enhancement of per-
needed to constrain dynamic modeling          meability within a fault as it moves in a
of earthquake ruptures (Avouac et al.,        series of small earthquakes, or the con-
2013)                                         trols on the magnitude of earthquakes
                                              induced by this mechanism.
In-situ experiments
To bridge the gap between simulated           Geological records of tsunamis
earthquakes in the laboratory (milli-         and earthquakes
metre to metre scale) and the kilometre       Geologists are always seeking new
dimensions of natural earthquakes, we         methods for extending the record of
need better knowledge about the behav-        past earthquakes and other large cata-
ior of materials for in-situ conditions.      strophic events beyond the written his-
Experiments at depth in real fault zones      torical record. Coastal deposits from
can study the conditions for producing        large tsunamis (produced by earth-
earthquakes using small displacements         quakes, volcanic events, meteorite
of the actual rock masses under natural       impacts), as identified in borehole cores,
stress and temperature conditions (e.g.       can be used to gain a better knowledge
Henry et al., 2013).                          of such events. Giant M earthquakes,
                                              such as the recent 2004 Sumatra, Indo-
29 SCIENCE PLAN ELEMENTS  / ACTIVE FAULTS AND EARTHQUAKES
                                                                                                                                                               ICDP

                                                                                     Tiberian Fault

                                                                      S France           Gulf of Corinth Aigion Fault          Wenchuan Fault

                               San Andreas Fault                    SE Iberia                 N Anatolian Fault
                                                                                                                                           Nojima Fault

                                                                                                                                      Chelungpu Fault
                                                                                                                   Koyna dam

       Fault zone drilling and borehole observatory                                          South African Goldmine
       Borehole observatory
       In situ experiment
                                                                                                                                                Alpine Fault

Figure 16. Locations of continental fault-zone drilling projects, borehole observatories and in-situ experiments discussed in the Active Faults and Earthquake
Processes session at the ICDP Science Conference.

nesia and 2011 Tohoku, Japan earth-                    Capture the complete
quakes produced global-scale tsuna-                    earthquake cycle
mis which can be studied using coastal                 Past drilling projects have investigated
boreholes (e.g. Fujiwara, 2013). Also                  fault zones soon after the occurrence of
records from regions that have very high               a large earthquake (e.g. Chelungpu and
sedimentation rates, such as glacial and               Wenchuan), while others have studied
lake deposits, can provide new opportu-                physical characteristics of faults in vari-
nities for extending earthquake histories              ous stages of the earthquake cycle. In the
(Toy et al., 2013b).                                   future, we envision a large-scale project
                                                       to make detailed subsurface observa-
Deep processes and tectonics                           tions before, during and after a large
In addition to providing detailed fault-               earthquake. For such studies, it is essen-
zone characterisations, observations                   tial to measure the physical state of the
made in boreholes provide the only                     fault before the event and have in place a
direct means for measuring the state of                borehole that can rapidly be reoccupied
stress in the Earth. Knowledge of the                  to observe the rapid temporal evolution
orientation and magnitude of the stress                of the fault immediately after a large
field and its spatial variability may hold             slip event. Clarifying time-dependent
the key to understanding the variability               changes in the physical and chemical
in earthquake rupture and seismic wave                 properties should lead to important new
radiation, as well as providing impor-                 insights for understanding the whole
tant constraints on regional tectonic                  process of earthquake occurrence.
processes and deeper mantle processes.
30 SCIENCE PLAN ELEMENTS  / ACTIVE FAULTS AND EARTHQUAKES
                                                                                                                                          ICDP

Drilling issues                               Recommendations

Reaching the depths of the seismogenic        1. Studying earthquakes using drilling
zone where earthquakes nucleate has           provides unique opportunities for high-
always been a challenge for fault-zone        profile, high-scientific return investi-
drilling projects. The maximum depth          gations that hold the potential to revo-
reached in a fault-zone drilling project      lutionise our understanding of active
was 3.0 km at SAFOD, although, for            faulting and earthquake processes.
comparison, exploratory oil and gas                                                         Figure 17. Two scientists holding a drill core that
                                                                                            contains the Alpine Fault, New Zealand.
wells have been drilled to over three         2. These questions are of high interest to
times this depth. For core sampling,          the public, so appropriate education and
there is the desire to reach greater depths   outreach efforts should be considered
and pressures which may be more rep-          from the planning stages. Furthermore,
resentative of the overall fault condi-       serious consideration should be given to
tions of a large earthquake. Obtain-          the practical applications of the scientif-
ing fault zone cores from depths of           ic results to seismic hazard evaluations
5 to 10 km will need new cost-effective       and mitigation.
techniques for deep drilling, including
advanced techniques for better recovery       3. ICDP workshops should be intro-
of the fragile fault zone.                    duced to discuss broader logistical and
                                              design issues common to all earth-
For borehole observatories, such as the       quake investigations, rather than just
GONAF array along the North Ana-              the development of specific drilling
tolian Fault in Turkey (Bohnhoff et al.,      proposals. Possible topics that would
2013), more numerous sites with rela-         be of interest to the scientific commu-
tively shallow boreholes are needed to        nity include technologies in borehole
emplace seismometres, strainmetres and        observatories, applications for seismic
other instruments in competent rock at        hazard assessment, and a roadmap for
a depth of a few hundred metres. ICDP         a coordinated global fault zone drilling
could lead efforts to develop efficient       programme.
drilling and deployment strategies for
such borehole installations.

Also, improved logging tools and new
techniques for analysing cuttings are
needed to optimise the information
gained during the drilling.
You can also read