Page 325 - Fundamentals of Gas Shale Reservoirs

INTRODUCTION 305
TAbLE 14.3 RFs used in EIA study (EIA, 2011a) shale gas formations in the EIA study. These two success/
risk factors are multiplied by OGIP to derive the risked GIP
Geologic Reservoir RF
Clay content complexity properties (%) for the prospective area. The TRR is established by multi-
plying the risked GIP by a shale gas RF listed in Table 14.3.
Low Low to moderate Favorable 30
Medium Moderate Average 25
Medium to high Moderate to high Below average 20 14.1.9 Shale Gas OGIP Assessment in North America
Dong et al. (2012) analyzed OGIP in the 16 North American
basins listed in Table 14.5. Shale gas resources were evalu-
TAbLE 14.4 Risked gas in place and technically recoverable ated and the results were published.
shale gas resources: five regions (EIA, 2011a) Smead and Pickering (2008) estimated shale gas in place
of 833 Tcf for eight US basins (Table 14.6). Kuuskraa and
Risked gas Risked technically Average Stevens (2009) completed in‐depth, basin‐level assessments
Region in place, Tcf recoverable, Tcf RF, %
for seven gas shales in six North American basins. He esti-
NAM 5,314 1208 23 mated that the resource endowment in these six basins is 4789
AAO 7,042 1800 26 Tcf. In the same year, DOE (2009) estimated the OGIP in
LAM 6,935 1906 27 Antrim and New Albany shales at 76 and 160 Tcf, respec-
AFR 3,962 1024 26 tively. Formations prospective for shale in the Western
EUP 2,587 624 24 Canadian Sedimentary Basin potentially contain 1380–1490
World 25,840 6562 25
Tcf of shale gas (EIA, 2011a; Kuuskraa and Stevens, 2009).

TAbLE 14.5 North American basins assessed
No. Nomenclature Full name No. Nomenclature Full name
1 APPB Appalachian Basin 9 ILLB Illinois Basin
2 ANAB Anadarko Basin 10 LMS Louisiana Mississippi Salt
3 ARKB Arkoma Basin 11 MICB Michigan Basin
4 BWB Black Warrior Basin 12 PERB Permian Basin
5 DENB Denver Basin 13 SJB San Juan Basin
6 ETB East Texas Basin 14 WGC Western Gulf Coast
7 FWB Fort Worth Basin 15 WILB Williston Basin
8 GGRB Greater Green River Basin 16 WCSB Western Canadian Sedimentary Basin

TAbLE 14.6 Comparison of original shale gas OGIP assessments by basin, in Tcf
Smead and Kuuskraa and DOE
Basins Pickering (2008) Stevens (2009) (2009) Others Dong et al. (2012)
ANAB 199 199
APPB 2100 1500 225248 Williams (2006) 1725–2348
ARKB 23 320 52 75–343
BWB 23 23
DENB 13 13
ETB‐LMS 790 717 717–790
FWB 168 250 327 168–327
GGRB 265 265
ILLB 160 160
MICB 76 76
PERB 265 265
SJB 61 97 Petzet (2007) 61–97
WGC 950 Hill and Nelson (2000) 950
WILB 15 15
WCSB 1380 1490 EIA (2011a) 1380–1490
TOTAL 833 4789 2832 4774 EIA (2011a) 4774–7341