Cana Woodford Shale Play, Anadarko Basin: The Effects of Mudrock Lithologies and Mechanical Stratigraphy on Completion and Production
Craig D. Caldwell Cimarex Energy Co., Tulsa, OK
2013 OK Shale Gas and Oil November 20, 2013 Norman, OK ACKNOWLEDGEMENTS Cimarex Energy Co. Devon Energy Corp. Weatherford Terra Tek Inc. Lynn Adams-Cimarex Energy •Introduction/Acknowledgements •Regional Maps- Overview •Geologic Provinces of Oklahoma •Woodford Isopach •Woodford Structure •Mechanical/lithostratigraphic model, mudrock lithologies, and their relation to completion •Regional variations in stratigraphy and lithology •Conclusions •Rock stuff Is there a relationship between Woodford rock types, mechanical/lithostratigraphy, completion, and production? ORD Anadarko Woodford Play
STRATCOLUMN MAJOR AND GEOLOGICPROVINCES OF OKLAHOMA
*After Johnson et al (2000)*AfterJohnson
Woodford Isopach Anadarko N Basin
NW Woodford Play
CORE SW
0 5 10
SE miles Top Woodford Structure N (MD) Anadarko NW Basin Woodford Structure mapCORE Play SW
0 5 10
SE miles Type Log from Core Area Showing Lithostratigraphy and % Clay for Middle & Upper Woodford
MISS
UW3 %Clay
UW2 14.5 UW
UW1
MW4
MW2 38.0
MW1C 27.4 MW
MW1B 36.3
MW1A 25.5 39.6 LW3 LW Woodford Rock Types Anadarko Basin Woodford Play
% GAS-FILLED Brittleness ROCK TYPE % QUARTZ % CLAY % TOC PRv POROSITY Index*
Siliceous mudrock 75.2 14.5 4.86 5.4 0.155 0.75
Clayey, siliceous 54.8 27.4 6.43 6.8 0.164 0.55 mudrock
Clayey mudrock 40.6 38 5.97 5.6 0.192 0.41
Organic-poor, clayey 27.3 52.4 0.6 1.8 0.25 0.27 mudrock
*B.I.=Quartz/Qtz+Carbonates+Clay (Sondergeld et. al., 2010) Anadarko Woodford Mineralogy (XRD) QUARTZ and Rock Types (and feldspar)
Siliceous mudrock Clayey mudrock Upper WDFD
Clayey, siliceous Organic-poor, mudrock clayey mudrock Middle & Lower WDFD
Basal WDFD
DOLOMITE CLAY and PYRITE Anadarko Woodford Mineralogy (XRD) QUARTZ and Rock Types (and feldspar)
Siliceous mudrock Clayey mudrock Upper WDFD
Clayey, siliceous Organic-poor, mudrock clayey mudrock Middle & Lower WDFD
BARNETT SHALE Basal WDFD
EAGLE FORD SHALE
CARBONATE CLAY
Barnett and Eagle Ford Mineralogy from Q. R. Passey Et. Al. 2010 Middle and Upper Woodford Lithostratigraphy, Anadarko Woodford Play – Core Area
MISS MISS
UW3 Quartz/Clay Siliceous mudrock 75/14 UW2 UW Clayey, UW1 siliceous mudrock MW4
MW2 41/38 55/27 Clayey MW1C mudrock MW MW1B
MW1A
LW3 LW Basal, Lower, & Middle Woodford Lithostratigraphy, Anadarko Woodford Play – Core Area
MW1B MW MW1A Clayey, siliceous LW3 mudrock Quartz/Clay LW2
41/38
LW1C Clayey 55/27 mudrock LW1B
LW Organic- LW1A poor 27/52 clayey LW1 mudrock BW
LW0
HNTN MISS Woodford Lithostratigraphy Siliceous mudrock UW Anadarko Basin Woodford Play Clayey, Core Area siliceous mudrock MW
Clayey mudrock
LW Organic- poor clayey mudrock BW
Hntn WDFD Thk. 290’ Frac' Success and Woodford Rock Types
ROCK TYPE % QUARTZ % CLAY % SUCCESS
Siliceous mudrock 75.2 14.5 100 Clayey, siliceous 54.8 27.4 86 mudrock Clayey mudrock 40.6 38 53
Successful frac' defined as one in which >75% of planned proppant amount was placed. Successful frac' defined Frac' Success and Woodford Rock Types % Success, % Success, ROCK TYPE % QUARTZ % CLAY % DOLOMITE Pre-HF w/ HF
Siliceous mudrock 75.2 14.5 2.8 100 100 Clayey, siliceous 54.8 27.4 3.6 86 94 mudrock Clayey mudrock 40.6 38 5.0 53 80
Successful frac' defined as one in which >75% of planned proppant amount was placed. Table drawn from 906 frac stages. Successful frac' defined Well Path Showing Woodford Lithostratigraphy and Lateral Placement
FRAC STG. LBS. SAND TRT PRES.
Fracture Conductivity versus increasing Closure Stress – 40/70 PRC Proppant
)
ft -
MW1C and MW1A
MW1B
MW2 Fracture Conductivity(md Fracture
No Proppant
Closure Stress (psi) Woodford Isopach
N Anadarko Basin NW Woodford Play
CORE SW
0 5 10
SE miles Woodford Lithostratigraphy Anadarko Basin Woodford Play - SE Area
MISS MISS
UW2
UW1 UW
Clayey, MW4 siliceous mudrock MW2 MW MW1C
MW1B
MW1A Clayey mudrock LW3 LW LW2
LW1B LW1A WDFD Thk. HNTN HNTN 110’ Woodford Isopach Anadarko N Basin
NW Woodford Play
CORE SW
0 5 10
SE miles MISS Woodford Lithostratigraphy Siliceous mudrock UW Anadarko Basin Woodford Play Clayey, Core Area siliceous mudrock MW
Clayey mudrock
LW Organic- poor clayey mudrock BW
Hntn WDFD Thk. 290’ WOODFORD CORE ANALYSIS
35011215000000 CHESAPEAKE FRIEDA 1-25 1320 FNL 1460 FWL BLAINE T13N R13W S25 ELEV_KB : 1,611
Rel Rel Depth(ft) Depth(ft) -200 -200
-100 -100
14900 SW AREA
MISS 0 WDFD 0
UW3
15000 WDFD-UW2 UW Siliceous mudrock UW2
Organic-
WDFD-UW1
poor, WDFD-MW4 100 clayey MW/LW 100
WDFD-LW3WDFD-LW1BWDFD-LW1AWDFD-LW1 mudrock WDFD-LW2WDFD-LW1C
LW1 Clayey 15100 mudrock WDFD_LW0 BW
LW0
HNTN HNTN 200 TOTAL WDFD 177’ 200 11/1981WDFD minus BW 111’
HS=1
PETRA 3/28/2012 3:43:01 PM (CDC_Freida 1-25_cross section.CSP)
Lateral Placement and EUR- CANA SW
35H
12H
10H
-
-
26H
-
-
28H
2H
32H
-
-
-
1H
-
TRIPLE 1 S TRIPLE 1 MEACHAM ABBOTT 1 ABBOTT 1 PROPPS 1 LIEBSCHER CANTRELL 1
MERRIETTA 1 MERRIETTA LEX LEX 1 KND 6 14 9 UW 21 3 28
48 UW 2 40 78 77 33 46 100 91 MW 30
BW 46 39 33 22 22 17
EUR 3.6 3.8 3.7 6.3 6.5 6.1 6.9 7.5 CONCLUSIONS:
Seven mudrock lithologies are defined, primarily on mineral content and percent TOC, and a mechanical/lithostratigraphic model is established for the central part of the Anadarko Woodford Play.
Core and frac’ data indicate that quartz-rich mudrocks and clay-rich mudrocks have distinctively different mechanical properties. Clay-rich mudrocks commonly treat at higher pressures and proppant placement can be challenging.
Embedment studies demonstrate lower fracture conductivity in more clay-rich lithologies compared to those observed in more silica-rich rock.
Regional work shows that in the SE Cana area decreased Woodford thickness and an overall increase in percent of clay-rich lithologies is associated with decreased well performance.
In the SW Cana area a relationship appears to exist between lateral placement and EURs.
An important part of any Woodford completion program should be the discussion of lateral placement.
Rock Stuff Thin Section Photomicrographs of Woodford Rock Types
UW1UW1 sample sample showing showing silicified silicified Tasmanites; MW1B sample showing detrital silt; sampleTasmanites; is 64% sample quartz isand 64% 21% quartz clay. and sample is 34% quartz and 38% clay. Siliceous21% clay. mudrock Silicic mudstone lithology. lithofacies. Clayey mudrock lithology. SEM Photomicrographs of Woodford Microfabrics
UW2UW2 sample sample showing showing microcrystalline microcrystalline silica with MW4 sample showing parallel alignment of silicaintercrystalline with intercrystalline porosity; sample porosity;is 76% quartz and illite clay; sample is 26% quartz and 44% clay. 18% clay. Silicic mudstone lithofacies. sample is 76% quartz and 18% clay. Clayey mudrock lithology. Siliceous mudrock lithology. Bed-limited dolomite-cemented fractures in thin silicic layers Siliceous mudrock lithology Silicic laminae with dolomite-cemented fracture Siliceous mudrock lithology
Porosity in organic laminae Clayey siliceous mudrock Parallel lamination in Clayey mudrock lithofacies Bioturbated bed Clayey mudrock lithofacies Image Log of Thin-Bedded Upper Woodford Woodford Lithostratigraphy With Sonic Scanner Data Woodford Lithofacies
BIOGENIC SILICA
DETRITAL CLAY AND SILT
Upper Woodford Middle/Lower Basal Woodford Woodford
Distal (?) Proximal (?)
“GOOD” MECHANICAL PROPERTIES “POOR” MECHANICAL PROPERTIES An Incomplete List of Things That Could Impact Cana Woodford Production
The Rocks The Completion
Thickness Lateral Length Brittleness Amount & Type Proppant Porosity/Perm Amount & Type Fluid Natural Fractures Number Stages Maturity Cluster Spacing Pump Rate Lateral Configuration Lateral Placement SW SE CORE Siliceous mudrock
Clayey, siliceous mudrock Regional Clayey Stratigraphic mudrock Variability Anadarko Woodford Play Dolomitic, Clayey mudrock
Organic- poor clayey mudrock
Organic- poor clayey mudrock II Average Treating Pressure of Woodford Stages, Dixie 1-4H
9
8
7 MW1C Stages shown in
6 yellow
5 Stage Stage 4
3
2
1
8000 8500 9000 9500 10000 10500 11000 11500 Average Treating Pressure (psi) WELL 1-4H WELL 1-3H EUR 6.4 BCF EUR 8.83 BCF 5%
52% UW1 14% Clay-rich mudrock ~2200’ 95% Silica-rich mudrock
48% Silica-rich mudrock
187 MB SW 186 MB SW 1.5 MM# 1.5 MM# 4128’/9 stgs 4087’/9 stgs Woodford Isopach N Anadarko Basin NW Woodford CORE Play SW
SE
0 5 10
miles