1. Petrophysical Characterization of the Barnett Shale: Progress Report
Jeff Kane
Bureau of Economic Geology
PBGSP Annual Meeting
February 27-28, 2006

2. Overview Database construction Geophysical log analysis model
Texas United Blakely #1
Summary
Jeffrey A. Kane, Bureau of Economic Geology , PBGSP Annual Meeting, 2/27-28/2006, Austin, TX

3. Database construction
Wireline database:
7 wells with geochemical data
2 with log data
1 with mineralogy data
1 with limited P & P data
1 with capillary pressure data
2 with core descriptions
Jeffrey A. Kane, Bureau of Economic Geology , PBGSP Annual Meeting, 2/27-28/2006, Austin, TX

4. Database construction
Many of these core data were recently provided by Dan Jarvie of Humble Geochemical Services.
Jeffrey A. Kane, Bureau of Economic Geology , PBGSP Annual Meeting, 2/27-28/2006, Austin, TX

5. Geophysical log modeling
A quick historical perspective
Mineralogical model
Kerogen issues
Jeffrey A. Kane, Bureau of Economic Geology , PBGSP Annual Meeting, 2/27-28/2006, Austin, TX

6. Geophysical log modeling – some history
Much of the methodology used today to come from work performed on the T.P. Sims #2 core (ResTech, 1991)
This methodology derives from work done earlier on the Devonian Shale (GRI, 1989)
Few data have been published subsequently.
Jeffrey A. Kane, Bureau of Economic Geology , PBGSP Annual Meeting, 2/27-28/2006, Austin, TX

7. Geophysical log modeling - Mineralogy
Jeffrey A. Kane, Bureau of Economic Geology , PBGSP Annual Meeting, 2/27-28/2006, Austin, TX

8. Geophysical log modeling - Kerogen
Kerogen is a wildcard
It appears as porosity on logs
It has a nominal density of about 1.0 to 1.2 g/cc
(but it is probably more variable)
It has a hydrogen index of about 0.65 to 0.70
(water = 1.0)
Jeffrey A. Kane, Bureau of Economic Geology , PBGSP Annual Meeting, 2/27-28/2006, Austin, TX

9. Geophysical log modeling - Kerogen
(from Guidry and Olszewski, 1990) where:
Wk is the weight of kerogen
TOC is the weight fraction of total organic carbon
S1 is the weight fraction of free oil
CS1 is the weight fraction of carbon in the free oil
Ck is the weight fraction of carbon in the kerogen
Guidry and Olszewski (1990) suggest 0.87 and 0.75 for CS1 and Ck respectively. Jarvie (1999) recommends a value of 0.83 for CS1.
Jeffrey A. Kane, Bureau of Economic Geology , PBGSP Annual Meeting, 2/27-28/2006, Austin, TX

10. Geophysical log modeling - Kerogen
where:
Vk is the volume fraction of kerogen
Wk is the weight of kerogen
rB is the bulk density
rk is the kerogen density
Jeffrey A. Kane, Bureau of Economic Geology , PBGSP Annual Meeting, 2/27-28/2006, Austin, TX

11. Geophysical log modeling - Kerogen
The preceding is from derived from core data, not log data
Initially, correlations have to be developed to estimate kerogen volume from logs
This work is currently in progress
Jeffrey A. Kane, Bureau of Economic Geology , PBGSP Annual Meeting, 2/27-28/2006, Austin, TX

12. Geophysical log modeling
We have a mineralogical model of clay, quartz, calcite, dolomite, pyrite, apatite, kerogen, and fluids (water and gas)
We have a set of logs that have known or estimated responses to each of these model points
We can construct a set of equations to describe these relationships
Jeffrey A. Kane, Bureau of Economic Geology , PBGSP Annual Meeting, 2/27-28/2006, Austin, TX

13. Geophysical log modeling
This leads to a set of simultaneous equations that allow us to solve for the volumes of the geologic constituents present
This is fundamentally the same approach used by programs such as ELAN™ and OPTIMA™
We use the Geolog™ package MultiMin™
Jeffrey A. Kane, Bureau of Economic Geology , PBGSP Annual Meeting, 2/27-28/2006, Austin, TX

14. Overview of what the logs show
Texas Blakely #1 wireline log analysis
Jeffrey A. Kane, Bureau of Economic Geology , PBGSP Annual Meeting, 2/27-28/2006, Austin, TX

15. Texas United Blakely #1
Jeffrey A. Kane, Bureau of Economic Geology , PBGSP Annual Meeting, 2/27-28/2006, Austin, TX

16. Texas United Blakely #1
Jeffrey A. Kane, Bureau of Economic Geology , PBGSP Annual Meeting, 2/27-28/2006, Austin, TX

17. Texas United Blakely #1
Jeffrey A. Kane, Bureau of Economic Geology , PBGSP Annual Meeting, 2/27-28/2006, Austin, TX

18. Texas United Blakely #1
Jeffrey A. Kane, Bureau of Economic Geology , PBGSP Annual Meeting, 2/27-28/2006, Austin, TX

19. Texas United Blakely #1
Jeffrey A. Kane, Bureau of Economic Geology , PBGSP Annual Meeting, 2/27-28/2006, Austin, TX

20. Texas United Blakely #1
Jeffrey A. Kane, Bureau of Economic Geology , PBGSP Annual Meeting, 2/27-28/2006, Austin, TX

21. Texas United Blakely #1
Jeffrey A. Kane, Bureau of Economic Geology , PBGSP Annual Meeting, 2/27-28/2006, Austin, TX

22. Texas United Blakely #1
Jeffrey A. Kane, Bureau of Economic Geology , PBGSP Annual Meeting, 2/27-28/2006, Austin, TX

23. Texas United Blakely #1
Jeffrey A. Kane, Bureau of Economic Geology , PBGSP Annual Meeting, 2/27-28/2006, Austin, TX

24. Summary We have just begun to build an extensive Barnett database
We already have a basic model to analyze the Barnett from wireline logs
Work to date suggest that logs will be of great value in providing detailed data on Barnett mineralogy and facies. More core-based work is necessary to verify this and and refine our initial model
Jeffrey A. Kane, Bureau of Economic Geology , PBGSP Annual Meeting, 2/27-28/2006, Austin, TX