Greater Kakwa area, Alberta, Canada - CSPG
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Greater Kakwa area, Alberta, Canada
• Modern Resources for supporting this study;
Darren Tisdale, Eric Keyser and Francois Legault
for many helpful discussions.
• Tom Moslow, Dave Smith, Rob Sadownyk & the
rest of the Canadian Hunter crowd.
• Greg Feltham, Pete Sutherland the Ikkuma crew
• Richard Harris and the Jupiter crew.
• Raphael Wust & Cory Twemlow at Trican
2
• Stratigraphic frameworks: within the Spirit River Formation as well as between Spirit River members & adjacent units (the importance of standardizing terminology). • Depositional models for the Falher G-H interval. • Petrographic observations in the G-H interval & influences on reservoir aspects.
• The lowest / oldest formally named Falher submember is the Falher F; however numerous well-sorted sandstone shingles occur beneath the Falher F conglomerate interval. • These horizons have distinct reservoir and exploitation attributes that differ from one region to another and from one horizon to the next.
Falher G/H
Falher D
ravinement Falher E (coastal plain)
surface Falher F1
Falher F2/F3
Wilrich
• Study area extends
Wapiti from the Front Ranges
outcrop belt (between
Grande Cache, Alberta
Redrock & Holtslander Ridge,
BC) and the south
Wapiti area, particularly
the Redrock and Route
Route fields).
• All available Falher and
Wilrich core between
townships 45 and 65
3W6 have been
analyzed.
6
Spirit River Formation
Greater Kakwa
Study area
Bluesky
Warters et al., 1999
• Places the Glauconite with the middle Spirit River (Falher F-G-
H interval.
• Erroneous correlation and should be discontinued.
Falher A-F Glauconite • Glauconite to the south; Wilrich- Falher to North. • But…… this correlation still infers that the Glauconite is interbedded with the Wilrich.
A
B
C
D H
E
F
G
• (unpublished framework by Smith (1983) in Jackson, 1984; Smith et
al, 1984; Rahmani, 1984).
• Subsequent authors (eg. MacDonald et al., 1988; Zonneveld and Moslow.
2004; Newitt, 2017) have continued the trend.
Newitt, 2017 • Sandstone shingles identified as Falher A-P interfingering with Wilrich shale.
• Drills at slower rates but • Drills much more rapidly. responds well to stimulation. • Excellent producer, wells • Prolific producer; hosts some are not as prolific as the of the best wells in the area. Falher G interval. • Example: 01-11-64-09W6 • Example 01-08-64-08W6 • Maintaining two discrete (but close) reservoirs horizons produces more opportunities. At current well spacing there is no direct pressure response in adjacent wells during fracs. • Regional trend of drier wells to southwest; richer wells to northeast. • Consistently ~20-30% overpressured throughout area.
North South
Falher E
Southern limit of
Falher F production
Falher F
Falher G
Falher H
Wilrich Fm.
Bluesky Fm.North South Falher E Falher F Falher G Falher H Wilrich Fm. Bluesky Fm.
North South
• Bluesky top denotes a coplanar TSE / maximum flooding surface. • Several sub-Falher H cycles. • Each the Falher H, G and F consist of several parasequences. • Major units bound by coal beds. • Overall progradational succession with some subsidence-induced ‘backsteps’
03-33
13-27
Falher F legacy field 12-22
06-30
15-12 01-07
Falher G and H sand shingles 08-07
08-01
16-21• Influence on depositional setting for sandstone shingle geometry, vertical architecture, and horizontal continuity • Lateral changes in architecture of individual shingles and shingle-sets. • Lateral variability of within-parasequence mineralogy and grainsize.
• Narrow inland seaway.
• Montane highlands to
west.
• Lowlands to south &
east.
• Seaway debouches into
northern sea (Palaeo-
Beaufort Sea).
• Albian (~ 103 mya)
• Southern transgressive
limit Calgary or south.
Adapted from Blakey, 2016
https://deeptimemaps.comFalher F
• Cored through the
Falher G
F-G-H succession
on the eastern side
of the study area.
Falher HFALHER
G 06-30-63-05W6 FALHER H INTERVAL
• Low trace fossil diversity.
• Common organics on bedding
planes.
• Numerous internal scour surfaces.
• Thick ‘clean’ sandstone interval.
• Siderite granules common in some
beds.
FALHER H
1 cm• Low overall trace fossil diversity
FALHER
(higher in heterolithic intervals).
F
• Common sand-sized siderite
FALHER
clasts on bedding planes.
G1
• Variable sandstone/shale ratio
(changes from base to top).
06-30-63-05W6
FALHER G
INTERVAL
FALHER
G2
FALHER
HFALHER G
• Prodeltaic succession, heterolithic,
common convolute bedding, low
trace fossil abundance and diversity.
24FALHER G
• Wave reworked deltaic succession,
common intraclasts, low angle to
trough cross-stratified
25FALHER G
• Upper shoreface intertidal sand bar on a
subsiding delta front setting, common
normal grading and draped ripples on
tidally influenced point bar deposits.
26wave-modified deltas
barrier
island
coal swamp
poorly drained
alluvial lowlands
meandering offshore
River systems sand shoals• Stressed environmental conditions: likely salinity stress, combined with seasonal temperature stress & periodic oxygen stress.
• Low biodiversity in all sandstone successions observed in core. • Low biodiversity in all silty shale / muddy sandstone successions observed in core • Strong local shingle persistence / much more variable on a regional scale. • Concentration of thick deltaic sand lobes in the Route-Red Rock fairway (abundant multilevel locations).
Tiger Shoal
Trinity Shoal
• Abandoned delta lobes; Cailloux Bay
reworked into barrier Isles Dernieres
islands (Isles Dernieres),
which eventually subside Ship Shoal
into subtidal bars.Caillou Bay
Caillou Bay
Timbalier Island
Ship Shoal
Caillou Bay Isles Dernieres
Isles Dernieres W
Ship Shoal
Ship Shoal
Isles Dernieres E
Cat Island Pass
Ship Shoal
Timbalier Island
Adapted from Penland et al., 19860m-
shoal crest
2m-
shoal front
4m- shoal base
lagoon
6m- distributary
delta front
8m-
prodelta Sharp-based stacked sandstone shingles, similar
in architecture to some
10m-
• Adapted from Penland et al., 1986• Narrow northern (subarctic) opening • Numerous rivers feeding basin, likely persistent basinwide salinity stress & seasonal stratification. • Short-run rivers on western margin: thus deltas and shoreface sand bodies are texturally & mineralogically immature.
• Falher G / upper H interval. • Wave-reworked deltaically influenced shoreface • Abundant intra-shingle erosional surfaces, commonly with phytodetrital lags
• Common in every core (& common in outcrop; Moslow, 1995). • Intra-unit erosional surfaces with abundant phytodetrital lags. • Proximal to deltas chert granule / pebble and siderite granule lags are common.
• Influence of mineralogy (constituent grains and cements) on the ‘drillability’ of individual sandstone shingles. • In the eastern side of the study area the Falher F-G-H intervals shows no real mineralogical differentation. • In the Redrock/Route area, the Falher G and H have markedly different grain and cement mineralogies.
• FALHER H; 2814.9m
Cht Cht
Alb
Alb Alb
Cht Cht
Cht Cht
Chl
Cht
OM
Cht
Sid Alb
Suture• 2793m
Albite
Dolomite
Quartz
K-feldspar
Albite
Quartz• FALHER G2; 2778.1M
Alb
Qtz Cht
Fe-Cal
xpl
Alb
Fe-Cal Cht
Alb
pplFe-Cal
Qtz og
Fe-Dol
Cht Qtz • Falher G in 08-01 is
dominated by chert
and quartz.
• Abundant & diverse
Fe-Cal carbonate cements.
Qtz og
Fe-Dol
Cht
Cht Qtz• Igneous, metamorphic & Sed
sedimentary rock
fragments.
Met
Rad
Qtz overgrowth-Falher F (fluvial / crevasse splay)
quartz
-Falher G1 (dist. channel)
-Falher G2 (delta front / shoreface) quartz arenite
-Falher H1 (delta front / shoreface)
-Falher H2 (delta front / shoreface) subarkose sublitharenite
-Falher H3 (proximal prodelta)
• Detrital mineralogy
• Alteration products &
cements not counted
No clear mineralogical evolution
Pattern consistent with source mixing
feldspar Rock fragments (incl. chert)-Falher F (fluvial / crevasse splay) quartz
-Falher G1 (dist. channel)
-Falher G2 (delta front / shoreface) quartz arenite
-Falher H1 (delta front / shoreface)
-Falher H2 (delta front / shoreface) subarkose sublitharenite
-Falher H3 (proximal prodelta)
• Detrital mineralogy
• Alteration products included
• Closer to original mineralogy
• Tighter groupings but only
accurate if carbonate
assumption is correct
Tighter clustering but pattern
still indicates source mixing
Feldspar Rock fragments (incl. chert)
(Fld + carb/2)-Falher G1-i (upper shoreface / foreshore)
-Falher G1-ii (upper shoreface / foreshore)
quartz
-Falher G1-iii (upper shoreface / foreshore) quartz arenite
-Falher G2 (upper shoreface / foreshore)
-Falher G (baymouth bar) subarkose sublitharenite
-Falher H (upper shoreface)
• Clear evolution from lithic
arkose in lower intervals to
litharenite in upper
• Much higher chert content /
carbonate content up section
mineralogical evolution from
lithic arkose to litharenite
feldspar Rock fragments (incl. chert)• Samples characterized by several phases of silica
cementation as well as several types of carbonate
cement including calcite, Fe-calcite, dolomite and Fe-
dolomite.
Falher G in 08-01-62-08W6, 3389.80; Degraded dolomite, ferroan
dolomite rim in a secondary chert cement matrix.Alb Fe-Dol
Alb
2778.1m, Falher G2
2759.5m, Falher F2
Alb
06-30-63-05W6,
06-30-63-05W6,
Alb
Qtz
• Clay rims common in most
Alb
units.
2793.0m, Falher H1
• Primarily illite; less
06-30-63-05W6,
commonly kaolinite.
Fe-Cal
ChtFalher G-H Paragenetic Succession Major Diagenetic Total Events Early Late Porosity Illite/Kaolinite Chlorite Si cement phases Fe-Calcite Compaction / stylolitization Dolomite Fe-Dolomite Feldspar dissolution / seritization Final Quartz cement
08-01 Falher G 06-30 Falher G
• Abundant chert granule layers. • Lithic arkose
• Sandstone consists primarily of • Moderate to abundant feldspar
a lithic arenite.
• Rare feldspar / abundant
• Sand-dominated; no chert
carbonate granules / pebbles.
• Chert / chalcedony cement • Common patchy clay rims on
common sand grains
• Rare clay rims on sand grains.
08-01 Falher H 06-30 Falher H
• Sand-dominated, granules- • Feldspathic litharenite to lithic
pebbles absent arkose
• Sandstone consists primarily of • (primarily albite; some K-spar)
a lithic arkose • Sand-dominated, rare chert
• Rare carbonate, abundant granule lags.
feldspar (albite). • Common patchy clay rims on
• Common patchy clay rims on sand grains
sand grains• The Spirit River Fm. in the study area produces from two discrete, parallel horizons; herein denoted the Falher G and Falher H. • Deposition of both units reflects coalescing river- and wave-dominated deltas, sourced by numerous short-run river systems, into a constrained inland seaway. • In the current exploration/exploitation fairway at Redrock and Route, the Falher G and H intervals exhibit contrasting reservoir attributes reflecting differences in grain and cement mineralogy.
• Reservoir rocks in the Falher G have a greater proportion of chert, abundant and diverse carbonate replacement, and more pervasive silica cements (quartz, chert & chalcedony). This results in a reservoir with lower ROP but excellent response to stimulation. • Reservoir rocks in the Falher H have a greater proportion of feldspar, less common carbonate, less pervasive silica cements and more common clay rims on sand grains. This results in a reservoir with higher ROP and good response to stimulation.
Modern Kakwa 16-18-64-8W6, Nov., 2017
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