Anticipated seismic response of reservoir sands in the Bossier Formation Upper Jurassic, Anderson co

1
Anticipated seismic response of reservoir sands
in the Bossier Formation (Upper Jurassic),
Anderson county, East Texas.

• Diego Alexander Valentin,
• Robert H. Tatham and Ron Harris.

2
Overview

• Introduction
• 1.1 Location and Generalities
• Problem
• Stratigraphy
• Dataset
• Methodology
• Where we are?
• What will be done?

3
1. Introduction
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1.1 Location and Generalities

• The Tennessee Colony field is located in The
  Anderson County (East Texas).
• Regionally this field is located in the central
  part of the East Texas basin (Klein G.D., et al
  2002).
• This Basin is limited to the east by the Sabine
  Uplift, to the south by the Angelina Flexure zone
  and to the West by the Mexia Fault zone
  (Williams, R. A. et al., 2001).

Sabine Uplift
Mexia Fault zone
Anderson county
Mount Enterprise fault zone
Angelina flexure zone
Modified from Williams, R. A. et al., 2001.
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1.1 Location and Generalties

• The Tennessee Colony field is composed of 11
  wells from which only 7 are currently producing
  dry gas.
• The reservoir sands are located in the middle
  part of the Bossier Formation (Upper Jurassic).

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Overview

• Introduction
• 1.1 Location and Generalities
• Problem
• Stratigraphy
• Dataset
• Methodology
• Where we are
• What will be done

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2. Problem

• Uncertainty in thickness and lateral distribution
  of the reservoir sand.
• Small acoustic impedance contrast between the
  reservoir sandstones and the encasing shales.
• Conventional seismic not enough to predict sand
  distribution

Pettet
Cotton Valley
Bossier
CVLM
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Acoustic impedance vs Poissons ratio for
Bossier Formation Well Gregory A-1
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Well Gregory A-1 16200-17600ft MD
Bonner Density 2.67g/cm3 Vp4400m/s Vs2605ms
York Ss Density 2.51g/cm3 Vp4709m/s Vs3008m/s
16400
Lower Bossier Shale Density 2.66g/cm3 Vp3750m/s
Vs2297m/s
17000
17400
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Amount of energy for the Rpp reflected wave at
the Bonner - York interface, well Gregory A-1
Bonner Density 2.67g/cm3 Vp4400m/s Vs2605ms
York ss Density 2.51g/cm3 Vp4709m/s Vs3008m/s
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Amount of energy of Rps reflected mode converted
waves at the Bonner - York interface, well
Gregory A-1
Bonner Density 2.67g/cm3 Vp4400m/s Vs2605ms
York ss Density 2.51g/cm3 Vp4709m/s Vs3008m/s
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Amount of energy of Rss(V) reflected mode
converted waves at the Bonner - York interface,
well Gregory A-1
Bonner Density 2.67g/cm3 Vp4400m/s Vs2605ms
York ss Density 2.51g/cm3 Vp4709m/s Vs3008m/s
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Amount of energy of Rss(H) reflected mode
converted waves at the Bonner - York interface,
well Gregory A-1
Bonner Density 2.67g/cm3 Vp4400m/s Vs2605ms
York ss Density 2.51g/cm3 Vp4709m/s Vs3008m/s
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Amount of energy of Rsp reflected mode converted
waves at the Bonner - York interface, well
Gregory A-1
Bonner Density 2.67g/cm3 Vp4400m/s Vs2605ms
York ss Density 2.51g/cm3 Vp4709m/s Vs3008m/s
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Amount of energy of Rpp reflected waves at the
base of Yorks Sand interface Well Gregory A-1
York ss Density 2.51g/cm3 Vp4709m/s Vs3008m/s
Lower Bossier Shale Density 2.66g/cm3 Vp3750m/s
Vs2297m/s
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Amount of energy of Rps reflected waves at the
base of Yorks Sand interface well Gregory A-1
York ss Density 2.51g/cm3 Vp4709m/s Vs3008m/s
Lower Bossier Shale Density 2.66g/cm3 Vp3750m/s
Vs2297m/s
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Amount of energy of Rss(V) reflected waves at
the base of Yorks Sand interface well Gregory A-1
York ss Density 2.51g/cm3 Vp4709m/s Vs3008m/s
Lower Bossier Shale Density 2.66g/cm3 Vp3750m/s
Vs2297m/s
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Amount of energy of Rss(H) reflected waves at
the base of Yorks Sand interface well Gregory A-1
York ss Density 2.51g/cm3 Vp4709m/s Vs3008m/s
Lower Bossier Shale Density 2.66g/cm3 Vp3750m/s
Vs2297m/s
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Amount of energy of Rsp reflected waves at the
base of Yorks Sand interface well Gregory A-1
York ss Density 2.51g/cm3 Vp4709m/s Vs3008m/s
Lower Bossier Shale Density 2.66g/cm3 Vp3750m/s
Vs2297m/s
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Overview

• Introduction
• 1.1 Location and Generalities
• Problem
• Stratigraphy
• Dataset
• Methodology
• Where we are
• What will be done

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3. Stratigraphy

• The Cotton Valley Sandstone and limestone and
  Bossier Shale Formations are parts of what is
  Known as Cotton Valley Group, mostly Tithonian
  -Berriasian (Upper Jurassic-Lower Cretaceous).
  Williams, R. A. et al., 2001.

Modified from Williams, R. A. et al., 2001.
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Bossier Formation Sequence Stratigraphic model
Cotton Valley Ss
SB3
PGC
LST
SB2
Upper Bossier
PGC
MFS
TST
SB1
Lower Bossier
LST
Modified from Klein and Chaivre, 2002.
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Sequence Stratigraphy

• The Bossier Formation can be divided in two
  sequences
• The first one is limited between the SB1
  (CVL-Bossier contact), and SB2 (intra Bossier
  boundary) was deposited during a TST.
• The upper sequence between the SB2 and SB3 is
  mainly a LST Prograding complex sequence caused
  by a drop in the sea level caused by a climatic
  change (Klein and Chaivre, 2002, Williams et al
  2001).

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Depositional systems map of the Upper Bossier Fm.
Anderson
Modified from Klein and Chaivre, 2002.
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Overview

• Introduction
• 1.1 Location and Generalities
• Problem
• Stratigraphy
• Dataset
• Methodology
• Where we are
• What will be done

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4. Dataset

• Well logs
• Gregory A-1, Gregory A-2, Gregory A-3, Royall
  A-1, Royall A-2, Royall C-1, TDC A-1, Toole A-1.
• Dipole logs Gregory A-1.
• VSP data
• Near offset pp wave well Gregory A-3.
• Near offset ss wave well Gregory A-3.
• Far offset pp and mode converted ps wave well
  Gregory A-3.
• Core information.
• 3D-3C seismic.

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Overview

• Introduction
• 1.1 Location and Generalities
• Problem
• Stratigraphy
• Dataset
• Methodology
• Where we are
• What will be done

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Methodology for the seismic Characterization of
the Bossier Formation
Available Data Checking
Literature review
Data Loading
Vsp fundamntals and understanding of the
stratigraphy and sedimentary basin evolution of
the Upper Jurasic of the East Texas Basin
Interpretation of the VSP data of the interest
horizon and well log evaluation
Understanding of the stratigraphic model for the
Bossier formation
AVO analysis of the different VSP available
surveys
Seismic Characterization of the Bossier Upper and
Lower units and correlation with well data
Test of the results in the Donatello 3D-3C seismic
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Overview

• Introduction
• 1.1 Location and Generalities
• Problem
• Stratigraphy
• Dataset
• Methodology
• Where we are?
• What will be done?

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6.Where we are?

• Data was received at the end of 2008.
• Data loading and QC.
• Literature review of VSP fundamentals, Bossier
  Fm., tight gas analogues and stratigraphy of the
  East Texas basin.
• Well correlations and log interpretation of the
  available data.

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Correlation between the Zpp (zero offset),
corridor and the synthetic log well Gregory A-3
Travis Peak
CV Sand
Bossier
York
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Correlation between the Zpp corridor and the far
offset pp VSP, well Gregory A-3.
Travis Peak
CV Sand
Bossier
Bonner
York
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Overview

• Introduction
• 1.1 Location and Generalities
• Problem
• Stratigraphy
• Dataset
• Methodology
• Where we are?
• What will be done?

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7. Work Plan

• Once the data had been loaded properly, the plan
  is to start interpreting the Bossier Formation
  units and other horizons in the processed VSP
  data.
• AVO analysis.
• Integration of the well core data and the
  stratigraphic model of the units to make a valid
  seismic characterization.
• Testing the characterization in the Donatello
  3D-3C survey in order to give validity to the
  model.

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• Thanks!

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Acknowledgments

• Robert H. Tatham UT at Austin
• Ron Harris Anadarko
• Thomas Hess UT at Austin