THE BOSSIER PLAY Tithonian OF THE

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THE BOSSIER PLAY (Tithonian) OF THE EAST
TEXAS BASIN Controls on Stratigraphy and
Play Concepts - UPDATE
George Devries Klein
SED-STRAT Geoscience Consultants,
Inc
Sugar Land, TX, 77479-2564

gdkgeo_at_earthlink.net
HOUSTON GEOLOGICAL SOCIETY
May 28,
2008

 
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OBJECTIVES 1). Establish Sequence Stratigraphic
Framework. 2). Identify Major Sand Facies 3).
Map Sand Facies and Identify Potential
Exploration Fairways 4). Tie
Stratigraphy Facies to Basin History 5).
Identify/Locate LEAD AREAS.
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• WHY THE INTEREST?
• Tight Bossier Sands contain reserves of 1-3 BCF
  
• gas per well (single sand units).
• Thicker Bossier Sands (or multiple sand units)
• generate 8 10 BCF gas per well
• Rare cases, up to 20-30 BCF gas per well
• 200 mmcf/day production Amoruso Field
• (4/5/2007 LEOR press release)
• (Source
  www.leorenergy.com/amoruso_field.php)

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Data from Joyce Dukes Reporting Service,
Kilgore, TX, via www.tylerpaper.com
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• METHODS AND TASKS
• Detailed interpretation of well-log
  cross-sections
• (13 lines, 151 wells)
• Detailed Analysis of 13 Seismic lines (840 Mi.)
• Identify All Major Sequence Boundaries and
• Systems Tracts (Methods of Mitchum et al,
  
• 1995 Van Wagoner et al,1990)
• Map Log Facies AND Seismic Facies
• Identify best prospective fairways.

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GLOBAL CONTEXT OF BOSSIER TIME
(From www.scotese.com, 2002
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• BOSSIER TIME Characteristics
• Global High Stand of Sea Level (Kimmeridgian)
• Time of Generation of Major Source Beds
• Tropical/Humid Paleoclimate
• Deep Weathering Shale Dominated System
• Bossier Low net/gross sand

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BOSSIER ISOPACH INDEX MAP
(Left map redrawn from Montgomery Karlewicz,
2001)
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NEW BOSSIER DISCOVERIES
(From Oil Gas Investor,, January, 2008, p.62)
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BOSSIER STRATIGRAPHY Two approaches
(Left redrawn from Montgomery Karlewicz, 2001
Right from Williams and Mitchum,
1997 their
fig. 7)
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WELL LOG CROSS-SECTION 6
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Seismic Dip Line (up-dip end)
(Published with permission of Seismic Exchange,
Inc.)
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Seismic Dip Line (down-dip end)
(Published with permission of Seismic Exchange,
Inc.)
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Seismic Strike Line
(Published with permission of Seismic Exchange,
Inc.)
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(No Transcript)
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DEPOSITIONAL SYSTEMS MAP
(Modified From Ewing, 2001)
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BOSSIER PLAY MAP
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NEW DISCOVERIES AND PLAY CONCEPTS COMPARED
N
PROBABLE
BASIN
FLOOR FANS
(From Oil Gas Investor, January, 2008, p.62)
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• IS THERE AN ALTERNATE EXPLANATION?
• YES, indeed!!
• Isopach map is dated no chance to update it.
• Possibly, Savell and Amoruso Fields could be
• within an incised valley (if exit points are
  
• further east) or outermost shelf edge.

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• UPSIDE POTENTIAL Amoruso Field?
• Leor Energy estimates 2 3 TCF Reserves
• (Source
  www.leorenergy.com/amoruso_field.php)

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(No Transcript)
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• BASIN INFLUENCE Burial History Data
• Bossier deposited during time of rapid
• mechanical subsidence.
• Deposition could not keep up with subsidence
• until sea level dropped (SB-2).
• PGC during time when deposition kept up with
• or exceeded subsidence rate.
• SB-2 may signify possible climate change
• favoring influx of sand.

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(From
Scotese, 2002,
www. Scotese.com)
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GEOLOGICAL CONCLUSIONS In Mud-dominated
systems, a drop in sea level will extend fluvial
systems basinward. An associated change in
climate is the Driver that disperses sand into
such settings. To find those sands, map the
sequence boundaries on Seismic Sections and look
for Sand signature indicators ABOVE the boundary.
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AND Map surfaces to identify possible canyons
and Incised Valleys. And use their exit points
to identify possible Basin Floor Fans!!!!
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The exploration potential of these findings
opens up many new sandy reservoir
possibilities in mud-dominated systems.
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• FUTURE OF BOSSIER PLAY??????
• Acreage Costs (Still High)
• Engineering at depths gt 19,000
• Creaming Curves.

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(From Snedden et al, 2002)
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(From Snedden et al, 2002)
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(From Seitz, J.N., 2002, Banc of America,
Security Energy and Power Conference)
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(From Snedden et al, 2002)
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BOSSIER PLAY MAP
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ACKNOWLEDGEMENTS Phillips
Petroleum Co. Kenneth R.
Chaivre David R. Fox
Scott McCullough
Lisa Ashabranner
Campbell Huntington John Havens _at_
Seismic Exchange Inc.