Application of Vitrinite Reflectance to the Woodford Gas-Shale Play ...

AAPG Mid-Continent October 12, 2009
Section Meeting
Application of Vitrinite
Reflectance to the
Woodford Gas-Shale Play
in Oklahoma
Brian J. Cardott
Oklahoma Geological
Survey

Woodford Gas-Shale Wells
Completed 2003–2009
1,259 Wells
14 Caney/Woodford
11 Sycamore/Woodford
293 Vertical Woodford
940 Horizontal/Directional
Woodford (75%)
1 Sylvan/Woodford

Geologic Provinces of Oklahoma
Northcutt and Campbell, 1995

Woodford Gas-Shale Wells
Completed 2003–2009

Isopach Map of Woodford Shale
From Comer, 1992

Hydrocarbon
generation depends on
type, quantity, and
thermal maturity
of organic matter
(kerogen)

What is Vitrinite
and Vitrinite
Reflectance?

Vitrinite is a coal
maceral (organic)
derived from the cell
wall material or woody
tissues of vascular
plants (post Silurian)

Vitrinite Reflectance (%Ro) is a
measurement of the percentage
of light reflected off the
vitrinite maceral at high (500X)
magnification in oil immersion
(average of many values)

Hydrocarbon Source Rocks
PEAK OIL GENERATION
OIL FLOOR
PEAK WET GAS GENERATION
PEAK DRY GAS GENERATION
WET GAS FLOOR
DRY GAS GENERATION LIMIT
DRY GAS PRESERVATION LIMIT
Modified from Dow
(1977), Houseknecht
and Spötl (1993),
Taylor and others
(1998), Lewan (2002)

Guidelines for the Barnett Shale
(Based on Rock-Eval Pyrolysis)
VRo Values
Maturity
1.40% Dry-Gas Window
From Jarvie and others, 2005

Eastern Oklahoma
Distribution
of 112
Woodford
Shale
samples with
vitrinitereflectance
data
Cardott, in
preparation

Isoreflectance Map of the Woodford Shale in
Eastern Oklahoma (Updated October 2009)
PETRA 10/6/2009 3:10:12 PM
0.57
0.51
0.67
0.59
0.6
0.72
0.57
0.56
0.56
1.07
0.64
0.64
1
1
1.03
0.9
2
2.29
1.31
0.56 1.61
1.56
0.82
1
0.94
3
2
CHOCTAW FAULT
MISSISSIPPIAN
& OLDER
OUTCROP
AREA
0.54
0.74
0.57
1
1.87
2.26 2.25
0.49
1.73
0.86
1.98
1.79
1.91
2.81 3.47
1.05
0.5
0.52
1.37
0.77
1.23 1.88
2.4 3.46
0.5
0.83
2 2.09
2.48
3.36
1.14 1.69
2.44 3.44
1.66
2.8
0.5 0.58
3.19
4.85
1.45 4.76
1.23 1.88 2.31 3.04 3.14
0.59
0.79
3.32
1.62 1.88
3.41
5.28
0.51
2.51 2.9 2.94 3.6 3.4
0.64
0.57
1.2
0.62
1.12
2.85
0.580.57
2.53
2.55
0.63 6.36
1.15 1.89 2.52 2.69
1.83 2.01 0.52
0.55 0.792.55
0.52
0.59
1.58 2.56
0.5 0.78
1 2.19
0.56
0.86
0.98
0.94
4
Mississippian and
Older Outcrop Area
(different than
Ozark Uplift
Province boundary)
Map prepared by
R. Vance Hall
using Petra
Cardott, in
preparation
1.26

Woodford
Shale
Structure &
Vitrinite
Isoreflectance
Map
1
2
-5,000
3
4
-10,000
-15,000

Woodford Initial Production
on Isoreflectance Map
1
2
3 4

Woodford Shale Only Oil/Condensate
Production (149 of 1,233 wells; 2005-2009)
1
2
3
4
Condensate
940 BBLS
540 BBLS (1 st 3-5
492 BBLS months)

Anadarko Basin
Woodford Shale
Isoreflectance Map
based on 81 wells
(Cardott, 1989)

Anadarko Basin (2007-2009)
Canadian
Blaine
Caddo
Woodford Shale
Isoreflectance Map
(Cardott, 1989)

Caddo
14W
13W
12W
11W
10W
9W
8W
Devon Energy
1-11H Ratliff
15N
Canadian
14N
Blaine
Initial Production
13N
12N
11N

14W
13W
12W
11W
10W
9W
8W
Produced
Liquids
15N
Canadian
14N
Devon Energy
1-11H Ratliff
Blaine
13N
Caddo
12N
11N

Anadarko Basin API
(2007-2009)
Canadian
Blaine
Caddo
Woodford Shale
Isoreflectance Map
(Cardott, 1989)

Devon Energy 1-11 Ratliff
(11-13N-10W; Canadian Co.)
172 MMcf
2,826 BBls
IP: 6,601 Mcfd, 105 Bopd
Cum: 1.25 Bcf (ave 3.4 MMcfd),
14,502 BBls condensate

Structure and Vitrinite Reflectance of
Woodford Shale, Southern Oklahoma
0.61 0.66
0.58
0.63
0.55
0.60
0.55
0.56
0.82
0.58
0.49
0.58
0.69
0.50 0.50
0.64
0.70
0.49
0.77
2.13
2.19
0.52
0.49 2.22
0.56 2.45
0.54
0.52
0.56
0.63 0.58
0.53
0.55
0.55
Cardott, in preparation

Depth (feet)
Southern Oklahoma VRo vs Depth
Vitrinite Reflectance (%Ro)
0.00 0.50 1.00 1.50 2.00 2.50 3.00
0
2,000
4,000
6,000
8,000
10,000
12,000
14,000
16,000
18,000
20,000

Ardmore Basin Woodford
(2005-2009)
Carter
Johnston
Marshall
Bryan

Ardmore Basin Woodford
(2005-2009)
Carter
Johnston
Marshall
Bryan

Ardmore Basin
Initial Production
Johnston
Carter
Marshall
Bryan

Ardmore Basin
(Woodford-Only Production)
Carter
Johnston
Marshall
Bryan

NE OK Woodford Initial
Production on Isoreflectance Map
0.6
0.8
1.0
1.2
2.0

NE OK Woodford Shale-Only Production
0.8
0.6
Some Biogenic
Methane (note
outcrop)
Cum 192 MMcfg,
10,422 Bo
1.0
1.2
2.0

SUMMARY OF WOODFORD GAS SHALE PLAY
‣Main Woodford Shale gas play is in eastern Oklahoma at
>1.15% Ro
‣Woodford Shale gas play in Anadarko Basin shelf @1.2-
1.5% Ro
‣Some Woodford Shale gas potential is in southern and
northeastern Oklahoma at

http://www.ogs.ou.edu
For more information,
please visit the
Oklahoma Geological
Survey Web Site