GRI-96/0182 rr DOE Boonsville 3-D Seismic Data Set A Technology Transfer Product Generated as Part of the Secondary Gas Recovery Project Bob A. Hardage, James L. Simmons, Jr., David E. Lancaster, Robert Y. Elphick, Richard D. Edson, and David L. Carr Supported by Gas Research Institute, the U.S. Department of Energy. and the State of Texas Bureau of Economic Geology Noel Tyler, Director The University of Texas at Austin Austin. Texas 78713-8924 1996
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GRI-96/0182 rr DOE
Boonsville 3-D Seismic Data Set
A Technology Transfer Product Generated as Part of the Secondary Gas Recovery Project
Bob A. Hardage, James L. Simmons, Jr., David E. Lancaster, Robert Y. Elphick, Richard D. Edson, and David L. Carr
Supported by Gas Research Institute, the U.S. Department of Energy. and the State of Texas
Bureau of Economic Geology Noel Tyler, Director The University of Texas at Austin Austin. Texas 78713-8924
1996
GRI-96/0182 Grl ® DOE
Boonsville 3-D Seismic Data Set
A Technology Transfer Product Generated as Part of the Secondary Gas Recovery Project
Bob A. Hardage.1 James L. Simmons. Jr.,1 David E. Lancaster.2 Robert Y. Elphick.3 Richard D. Edson,1 and David L. Carr4
1 Bureau of Economic Geology. The University of Texas at Austin 2S. A. Holditch & Associates. Inc., College Station. Texas 3Scientific Software-Intercomp, Inc.. Denver. Colorado 4Consulting Geologist, Austin. Texas
Supported by Gas Research Institute, the U.S. Department of Energy.
and the State of Texas
Bureau of Economic Geology Noel Tyler, Director
The University of Texas at Austin Austin. Texas 78713-8924
1996
Legal Notice This seismic and well log data set was prepared by the Bureau of Economic Geology as an
account of work sponsored by Gas Research Institute (GRI). Neither GRI, members of GRI, nor any person or organization acting on behalf of either
a. Makes any warranty or representation, express or implied, with respect to the accuracy, completeness, or usefulness of the information contained in this seismic and well log data set, or that the use of any information, apparatus, method, or process disclosed in this seismic and well log data set may not infringe privately owned rights, or
b. Assumes any liability with respect to the use of, or for any and all damages resulting from the use of, any information, apparatus, method, or process disclosed in this seismic and well log data set.
This technology transfer product contains the following:
• 5.5 mil of time-migrated 3-D seismic data, • digitized well log curves from 38 wells inside this 3-D seismic grid, • depths to the boundaries of many Bend Conglomerate genetic sequences interpreted
from these logs, • perforation depths, reservoir pressures, and production and petrophysical data for the
38 wells, and • vertical seismic profile (VSP) data and explosive-source checkshot data recorded in a
calibration well near the center of the seismic grid.
Use of the data:
We encourage use of this data set and welcome suggestions for the development of future digital products. This data set may be used for research and demonstration purposes provided that the authors, publisher, and supporting organizations are acknowledged. Components of this data set are considered a single product for use on one computer by one user. Any requests to use these data in any other way must be made in writing to the Director, Bureau of Economic Geology, The University of Texas at Austin.
Cover: Interpreted time-structure map of the top of the Caddo, which is the shallowest genetic sequence in the productive Bend Conglomerate section (fig. 3). Features 1, 2, and 3 are circular depressions created by karst dissolution and collapse in the Ellenburger carbonates (Ordovician) some 2,000 to 2,500 ft (610 to 760 m) below this siliciclastic Caddo (Middle Pennsylvanian) sequence. The downward continu-ation of these karst-generated collapse features appears in figure 6 in the text, which is the time-structure map of the top of the Vineyard sequence approximately 1,000 ft (305 m) below the Caddo (fig. 3).
Contents Summary 1
Project study area 2
Overview of public data base area 2
Detailed map of public data base area 3
3-D seismic data 3
Well log data 3
Sequence stratigraphy information 3
Reservoir engineering data 4
VSP and checkshot data 4
Acknowledgments 34
References 34
Appendix 35
Figures
1. Middle Pennsylvanian paleogeographic map showing the Fort Worth Basin and other basins related to the Ouachita orogeny and the Boonsville project area 5
2. Generalized stratigraphic column for the Fort Worth Basin 6 3. Stratigraphic nomenclature used to define Bend Conglomerate genetic
sequences in Boonsville field 7 4. Number of net-pay intervals occurring between the Caddo and Vineyard
sequences across the Boonsville study area 8 5. Distribution of net hydrocarbon feet between the Caddo and Vineyard
sequences 9 6. Interpreted time-structure map of the top of the Vineyard sequence 10 7. Seismic reflection amplitude response on the Vineyard surface 11 8. Seismic profile ABC 12 9. Map of public data set area showing inline and crossline coordinates of
the 3-D seismic grid and locations of the wells within the grid 13
Tables
1. Seismic inline and crossline coordinates of well data base 14 2. Digital log data provided for wells 15 3. Boonsville public data set log depths of interpreted genetic sequence boundaries 17 4. Perforation, production, pressure, and petrophysical data 20 5. Velocity checkshot data 32
iii
Summary This 3-D seismic data set is made publicly available as a part of the technology transfer
activities of the Secondary Gas Recovery (SGR) program funded by the U.S. Department of Energy and the Gas Research Institute. The data are a significant part of the total data base amassed during a 2-year SGR study of the Bend Conglomerate reservoir system in Boonsville field, located in the Fort Worth Basin of North-Central Texas.
The objective of this publication is to provide the public with an affordable copy of digital 3-D seismic data, together with supporting geologic and reservoir engineering information, which can be used for educational and training purposes for a broad range of industry and academic interests. This data set should be particularly appealing because the 3-D seismic data have a high signal-to-noise ratio and a wide frequency range of approximately 10 to 115 Hz. When coupled with the geologic and engineering control provided with this publication, the 3-D data present a challenging opportunity to study a complex reservoir system of genetic sequences (sensu Galloway, 1989) that were deposited in a low- to moderate-accommodation basinal setting. The 3-D data also show how karstification of deep Ellenburger carbonates has generated collapse structures that have compartmentalized siliciclastic Bend Conglomerate reservoirs 2,000 to 2,500 ft (610 to 760 m) above the depths where the collapse structures originated, which is perhaps the most important geological phenomenon represented by these Boonsville data.
This public data set consists of the following components: • 5.5 mil of time-migrated 3-D seismic data, • digitized well log curves from 38 wells inside this 3-D seismic grid, • depths to the boundaries of many Bend Conglomerate genetic sequences interpreted
from these logs, • perforation depths, reservoir pressures, and production and petrophysical data for
the 38 wells, and • vertical seismic profile (VSP) data and explosive-source checkshot data recorded in
a calibration well near the center of the seismic grid.
The 3-D seismic data are provided on an Exabyte tape in SEGY format; the digital well log data are ASCII files on 3.5-inch floppy disks; well completion, production, pressure, and petrophysical data are provided as a digital spreadsheet file on the disks and also as a tabular listing (table 4); VSP data are digital SEGY files on the disks; and all other geologic and geophysical data are given in tables 3 and 5.
Anyone who benefits from the public availability of these data should be particularly appreciative of three companies—Arch Petroleum (and their production company, Threshold Production), Enserch, and OXY USA, Inc. Collectively, these three companies operated all of the property inside the SGR Boonsville study area, and they were industry partners with the Bureau of Economic Geology in the reservoir characterization study that amassed this data set. Arch, Enserch, and OXY paid approximately 90 percent of the cost of the 3-D seismic data acquisition and processing, yet they are graciously allowing the public to have access to, and to benefit from, these data.
The SGR Boonsville study area is located in Jack and Wise Counties in the Fort Worth Basin in North-Central Texas (fig. 1). The accomplish-ments achieved in the 2-year study of this project area are described in a two-volume report by Hardage and others (1995), which is publicly available through the Gas Research Institute (phone 312-399-4601).
A generalized post-Mississippian descrip-tion of the stratigraphy of the Fort Worth Basin is shown by the stratigraphic column in figure 2. Several formations, extending from the Ellen-burger (Ordovician) to the Strawn (Middle Pennsylvanian), produce hydrocarbons in the
Boonsville area, but only the Atokan Bend Conglomerate reservoir system is described by the geologic and engineering components of this data base. The Bend Conglomerate is defined as the interval from the base of the Caddo Limestone to the top of the Marble Falls Limestone (fig. 3). Within the SGR study area, the thickness of the Bend Conglomerate ranges from 1,000 to 1,200 ft (305 to 365 m). Numerous genetic sequences exist within this interval; 13 are illustrated in the type log in figure 3. Other genetic sequence boundaries are defined in the accompanying geologic data base.
Overview of Public Data Base Area
The total data base involved in the Boonsville study consists of 26 mil of 3-D seismic data, VSP and checkshot control from five wells, and geologic and engineering information from more than 200 wells. The data that are publicly released through this publication are a carefully chosen subset of this larger data base, consisting of 5.5 mil of full-fold, time-migrated 3-D data near the center of the 26-mil seismic grid, VSP and checkshot control from 1 centralized well, and geologic and engineering data from 38 wells. The boundaries of the public data area are shown in a series of maps included as figures 4 through 7.
The most productive reservoir sequences described by this data base are the Caddo and Vineyard, the units at the top and near the base of the Bend Conglomerate (fig. 3). The map in figure 4 documents how many Bend Conglom-erate net-pay intervals exist between these two primary reservoir sequences across the study area. The public data set is thus deliberately positioned so that it spans a region where there is significant lateral and vertical variability in the productive potential of the central portion of the Bend Conglomerate section. The map in figure 5 illustrates the amount of net hydrocarbon feet that exists between the Caddo and Vineyard
levels. This display reinforces the concept that the public data span an area of considerable variation in reservoir facies, which allows users to evaluate data that describe both high- and low-productivity areas of the Bend Conglomerate.
The displays in figures 6 through 8 illustrate some of the intriguing seismic phenomena that are demonstrated with the public 3-D seismic data. Figure 6 is a seismic time structure map of the top of the Vineyard sequence, which is located near the base of the Bend Conglomerate (fig. 3). Several circular or quasi-circular depressions occur across this surface. Hardage and others (1995) explained that each of these depressions is a structural collapse of the Bend Conglomerate strata and that each collapse is genetically related to karst dissolution of Ellenburger carbonates some 1,000 to 1,500 ft (305 to 455 m) below the Vineyard level. The public 3-D seismic data are positioned so that the 3-D image spans several of these karst features. Figure 7 illustrates the reflection amplitude behavior across the top of the Vineyard sequence. Each white area in this display indicates a localized area where the reflection amplitude weakens and becomes distorted. Each of these disruptions in the Vineyard reflectivity corresponds to one of the karst-generated depressions in figure 6. Thus,
2
the public 3-D seismic data allow the reflection character of several of these karst phenomena to be studied in detail by those who wish to understand how deep carbonate dissolution affects overlying strata.
The profile labeled ABC in figure 7 traverses three of the disruptions on the Vineyard surface,
one rather large area of disruption located between A and B, and two smaller areas be-tween B and C. This profile is shown in figure 8 to illustrate how these karst collapse effects appear when they are viewed in a vertical section display.
Detailed Map of Public Data Base Area A more detailed depiction of the area
spanned by the public data set is provided by figure 9. This map specifies the inline and cross-line coordinates of the 3-D seismic grid, locates
3-D Seismic Data The seismic data provided on the Exabyte
tape are 3-D time migrated; no field records or unmigrated data are released in this publication. The digital seismic data exist as a time-migrated 3-D data volume composed of stacking bins
the VSP and checkshot calibration well (Billie Yates 18D), and sites all of the wells where geologic and engineering control is provided.
measuring 110 x 110 ft (33 x 33 m). The seismic reference datum is +900 ft (274 m). Specific information for reading this seismic data file is given in the appendix and on the sheet inserted in the tape box.
Well Log Data The wells included in this public data set
are sited on the map in figure 9. The specific inline and crossline coordinates for each well in the seismic grid are listed in table 1. The well log data for each well are listed in table 2. These
well log curves are digitized at depth increments of 0.5 ft (0.15 m) and are provided as ASCII files on the enclosed floppy disks. Specific instructions for reading these ASCII data are given in the appendix.
Sequence Stratigraphy Information Several genetic sequence boundaries have
been interpreted from the Boonsville well log data (table 3). These boundaries are designated by the descriptive abbreviations MFS, FS, or ES, and each of these abbreviations is then followed by a sequence code number N, where
MFS = maximum flooding surface, FS = flooding surface, ES = erosional surface, and N = a code number that identifies the
sequence.
The sequence code number N decreases as depth increases, with 90 referring to the Caddo sequence at the top of the Bend Conglomerate and 02 referring to the deepest Bend Conglomerate sequence just above the Marble Falls Limestone (fig. 3). The depths of the genetic sequence boundaries that have been interpreted at each of the wells are listed in table 3. These depths are measured relative to kelly bushing (KB). The deepest sequence boundary listed in this public data set is MFS10.
3
Reservoir Engineering Data
Company and public records were searched to build the reservoir engineering data base used in the Boonsville study. The information in this engineering control includes such parameters as perforation depth, initial reservoir pressure, and
volume of produced hydrocarbons. The engineering and petrophysical data amassed for the 38 wells composing this public data base are summarized in table 4. All depths listed in this table are measured from kelly bushing.
VSP and Checkshot Data
Both vibroseis-source VSP data and explosive-source checkshots were recorded in the Billie Yates 18D well and are included in this public data set. The location of the B. Yates 18D well is shown in figure 9, and its geographic coordinates are defined in table 1. The VSP data consist of two image profiles, each of which is a separate file on one of the enclosed disks. Image 1 is an offset profile that extends N18°E away from the B. Yates 18D well for a distance of 1,100 ft (335 m) (the vibrator was offset 2,752 ft [840 mi in this azimuth direction). Image 2 is a zero-offset profile.
The sources used for the 3-D seismic acqui-sition were small directional charges placed in shallow 10-ft (3-m) shot holes. A technical description of these specific directional charges is provided by a publication available from the Bureau of Economic Geology or the Gas Research Institute (Bureau of Economic Geology, 1995). For reasons of economy, vibrators were used as the
energy sources for the VSP data acquisition rather than drilled shot holes. Following the completion of the vibroseis-source VSP data collection in the B. Yates 18D well, an explosive-source checkshot survey was recorded so that the traveltime coordinates of the vibroseis-source VSP data could be adjusted to the traveltime coordinates of the 3-D seismic explosive-source wavefields, if significant traveltime differences occurred between the wavefields produced by these two energy sources. Traveltime differences of 6 to 10 ms do exist between the vibroseis and explosive wavefields, but in most applications using these public data, these differences can be ignored. However, for completeness of the public data package, the downhole seismic measurements recorded for both vibroseis and explosive sources are included in this publication. The explosive-source checkshot data and the equivalent zero-offset vibroseis checkshot data are listed in table 5.
4
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Figure 1. Middle Pennsylvanian paleogeographic map showing the Fort Worth Basin and other basins related to the Ouachita orogeny and the Boonsville project area. The solid rectangle on the Wise Jack county line designates the area where the 3-D seismic data were gathered.
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5
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Figure 2. Generalized post-Mississippian stratigraphic column for the Fort Worth Basin. The geologic and engineering data components of the public data base are restricted to the Bend Conglomerate interval, which in Boonsville field is equivalent to the Atoka Group shown here. The specific stratigraphic nomenclature used in this Boonsville study is described in figure 3. Modified from Thompson (1982).
6
*Main target zone in past Best gas-reserve-growth potential
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Bureau of Economic Geology sequence nomenclature
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Figure 3. Stratigraphic nomenclature used to define Bend Conglomerate genetic sequences in Boonsville field. As defined by the Railroad Commission of Texas, the Bend Conglomerate is the interval from the base of the Caddo Limestone to the top of the Marble Falls Limestone; however, the Caddo was also included in this particular study. The term MFS is an abbreviation for maximum flooding surface.
7
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Figure 4. Number of net-pay intervals occurring between the Caddo and Vineyard sequences across the Boonsville study area. The outlined area defines the boundaries of the public data set.
8
Net hydrocarbon feet > 2.0
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Net hydrocarbon feet < 1.5
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Figure 5. Distribution of net hydrocarbon feet between the Caddo and Vineyard sequences. The outlined area defines the boundaries of the public data set.
9
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Figure 9. Map of public data set area showing inline and crossline coordinates of the 3-D seismic grid and locations of the wells within the grid. Company names (Arch, Enserch, and OXY) indicate leaseholder at time of publication.
13
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18701
03
.82
187
0442.6
2
18
67
14
6.6
4
~ 1
865098
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186
6494.1
1
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70
590.1
9
18691
19
.42
18
776
91
.27
187
787
7. 32
187
8813.3
4
186957
8.3
0
18652
51
. 46
18
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579.0
7
187
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8
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7 000
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1
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73
648.4
8
18
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522
. 05
1 872
33
0.0
4
18
70754. 2
6
1872
586.0
2
18
73
547.1
4
187
1505.6
0
18694
07. 3
9 I
N •:1' C6 CO CO IC) ~ CO 1
87 4
545.5
8
187
432
4.2
7
18
751
51. 0
5
18
750
99
.15
187674
4. 5
7
1874
721.
00
41-a ~ ~
J 33.2
07
13
33.2
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3
33.2
01
18
I 33.1
9297
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O) r
coM 33.2
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80
33.1
9870
33
.1987
2
33
.1988
4
(C) O N
coM 33
.1972
7
33.1
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33.1
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01
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.18674
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97
_
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8
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33
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33.1
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co ~ r
coM 33.1
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ngit
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co O)
O O) . ~ 9'
r (") .4 CO O O) . r~ 9'
O CO O O) . ~ 9'
r ~ co
O O) . ~ 9'
O) O O) O) co . ~ 9' -9
7. 8
9452
-97.
89385
-97
. 90
594
CO (0 V N O) . r~ rn -9
7.9
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-97.
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4
LC) CO ~ N O) . ~ rn
O CO O) O) co . n rn -9
7. 8
992
2
CO
O O) co . r rn -9
7.9
264
2
-97. 9
4043
-97
.93
28
4
I-
o N O) . ~ rn
O O) v N O) . ~ rn
O) O) N_ O) . ~ rn -9
7.9
134
2
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7.9
224
5
-97.9
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8
-97. 9
1335
-97.9
2000
f~ CO CD N O) . ~ rn -9
7.9
0572
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CO O O) . ~ rn -9
7.9
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12
~ N CO O O) . ~ rn
(D CO N O co . n rn -9
7.9094
8
AP
I nu
mb
er
42
497
0137
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I
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37
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0
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0137 4
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7200
4
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01
37
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0
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49732
41700
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2370
15
5600
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2370
15
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1 42
23
70
26
1200
I 42
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7356
6300
I 42
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367
1100
I 42
237381
30
00
1 424970164200
I 42
497
0163
20
0
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6060
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730
2800
0
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22
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900
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0259
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1
42
23
70
25
93
00
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I 42497
3231
60
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3243400
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23
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6730
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42
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3247
800
424973251
40
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4223
7367
0200
I
4223
7380
0600
I 4
24
970
2142
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142
49
732
2240
0
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4973
2394
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4249
7325
3200
424
97
3253
400
424
9 70
1656
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4249732
2730
0
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ll n
ame
1Ash
e B
2
1Ash
e B
3
1Ash
e C
l
1Ash
e C
2
1Ash
e C
3
1Ash
e C
4
1Ash
e C
5
1Ash
e C
6
1B Y
ate
s 2
1B Y
ates
3
1B Y
ate
s 7
1B
Yat
es 1
1
1B Y
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s 13
1B Y
ate
s 1
5
B Ya
tes
18D
1Cra
ft W
B 12
-1
Cra
ft W
B 2
1-1
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ft W
B 21
-2
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ate
s 9
IF Y
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s 7
IF Y
ate
s 10
11.G
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es
3
11. G
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es 4
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s 9
11. G
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es
13
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tes
14
11. G
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tes
18
11
. G. Y
ate
s 19
1 1.G. Y
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s 2
1
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s 31
11.G
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es
32
1L. O
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er
1
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1
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re 2
14
Tab
le 2
. Dig
ital lo
g d
ata
pro
vided
for
wel
ls.
J
N 2
X X X X X X X X X X X X X X X x X X X X X x X X X X X X X X x
J Q U
X X X X X X X X X X X X X
O cc v X X
I-
G X X X X
LL
â X X X X X X
CO
= C<
X X X X X X X X X X X X X
= a z
x X X X X X X x x x x
°C c) x x X X X X x X X X X X X X X x x
N x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x I- 4 J
x x x
Z J X X
Z 0 X X X X X X X X X X X
0 CC (.7 cn
X
co J J
X X
CO
J X X X X X
J LL ci)
X X x X X X x X
2 J_ ~
X X X X X X X X X X X X X X X X
cm J_ ~
X X X X X X X X X X X X X X X X X x X X x X X X X X X X X X x
Lat
itu
de
3
3.2
07
13
j
CO N 'Tr O N M co 3
3.2
01
18
N- M N 0)
CO co
CO r CD 0)
CO co
~ 33.2
02
80
33.1
98
70
33.1
987
2
71- CO CO 0)
CO co
N LO N O N CO co 3
3.1
972
7
O ~ r CO0)
CO co
tn O 0)
CO co 3
3.1
92
59
33
19301
1 33
.18
67
4
33
.192
97
33
.19294
332
07
53
33
.18
008
V N- CO CO
CO co 3
3.1
858
9 1
33
.178
73
CO Co
M
CO co 3
3.1
849
6A
33
18150
N- co
07
CO co 3
3.1
85
04
I
33.1
875
3
33.1
82
60
N O tl) 00
CO co 3
3.1
89
03
N O •zr CO
CO co 3
3.1
8759
Lo
ng
itu
de
CD 0) ~ O 0) . N.: 0)
V co CO O
r` 0)
Q) .
-97.9
0160
CO *- ~ O Cn . ` O
0) O O 0)
r` (3)
CO .
-97
.89
452
-97
. 89385
~ O) ln O 0) . ~ 0)
CD CD ~ N
r` 0)
CT) .
-
97
. 92
35
7
-97
. 9343
2
N O
~
r` O -9
7. 9
36
42
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97
.92304
0) .
-97.
927
85
-97
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-97
. 89922
CD
CD 0)
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7. 9
264
2
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.
-97
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43
-97. 9
3284
n — O
Cc; ) . r` Q)
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0) Q) N
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N ~ CO
0) . ~ Q)
O Co f~
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O) .
-97
. 92
24
5 I
CO ~ CD
r\ 0)
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-97
. 91335
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N N- in O
r` 0)
0) .
-97
. 910
07 I
,— CO O
O) . ~ O)
AP
I nu
mb
er
424970
1378
00
42
49
701
37
700
42
49
701
37
400
42
49
70137300
42497
01
37
200
42
49
70
13
71
00
42
49
70137000
42
49
73
241
70
0
42
23
70
15
5600
4223
701
55700
42
23
702
61
20
0
42
2373031500
4223735
66
30
0
42237
36
71100
42
23
73
81
300
0
142
49
70
164
20
0
142
49
70
16
3200
142
49
70
160600
142
23
73
028000
142
23
70
259
900
142
23
70259
60
0
142
23
70
25
93
00
~42
23
70
25
9200
142
49
732
31
60
0
142
49
73243300
142
49
732
43
40
0
422373467300
24
97
3247
800
42497
32
51400
42
23
73
67
0200
422373800600
42
49
70
21
4200
42497
32224
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424973239400
Well
na
me
IAsh
e B
2
CO CO
a) L up Q
U a) L cn Q A
sh
e C
2
Ash
e C
3
Ash
e C
4
Ash
e C
5
lAsh
e C
6
B Ya
tes
2
B Ya
tes
3
IB Ya
tes
7
N ra >- CO B
Yate
s 1
3
B Y
ate
s 15
B Y
ate
s 1
8D
Cra
ft W
B 1
2-1
Cra
ft W
B 2
1-1
Cra
ft W
B 2
1-2
IC Ya
tes
9
IF Y
ate
s 7
IF Y
ates
10
II G
. Ya
tes
3
II. G
. Y
ate
s 4
II. G
. Ya
tes
9
1I.G
. Y
ate
s 13
11.G
. Y
ate
s 1
4
IG. Y
ate
s 18
I. G.
Ya
tes
19
I. G.
Ya
tes
21
I. G.
Ya
tes
31
I.G.
Ya
tes
32
~L. O
. F
an
che
r 1
IL. O
. F
anch
er
2
IL. O
. F
anch
er
3
15
X X X X
J
U
X
o m U
2
I-- J W
o _ m
X
We
ll n
am
e
O.
Fanche
r 4
L.O
. F
anch
er
5
W D
ew
bre
1
W D
ewb
re 2
x a z cc ~
a ~ X X X X
f- *g( J z J z ~
X
CO
-J - J
X
X
J J
X
-J ~ Cf)
2 _ J ~
X X
J_ X X X X
d
03 J
CV M O
~
O CO
C') M
co O N-
C")
V O co
M
CV
CA O rn r rn
~ N CO O CT) r
co co N O an r
424
97
3227300
42
49
73
25
320
0
42
49
73
25
34
00
AP
I n
um
be
r
42
49
70165600
Tab
let (c
on
t.)
3 .E = a) co o E12
>,
~~
a) >. -5 Q) >
cs)o
> .? in ~
E ~
Ç
~'
-a -o~ U) > C ~~ > ~
~ v) ~ •~ > - O Û>„ ~
-> ~ 5 U~ _
-0Q) C O >>~ N >
C
~ O
,-- O ? >,C' 0 7.7) N Q) a O _ `. o S p cn ~ ~`.~ 0 _d ç
_
U -o >,~ ~ ü (t a ~> ~ U §~ 7 c — C) N mEE O ~~' Û C Q)
17
Q) C E
~_O
_ c:
°UQ0 0 o ~ O E C 2 V • CM L O 0 0~C V l
~ `` °' °~ ~ ° ai ts mmrLc Q Q) a c ti 0 c~ Q cc o .c o .0 cti U
0 ~ n J J c/) Cn J
J(n (~ U m d o2 U 2
II II II II II II II II II II II II II II II II II II
c a~J =
O L J~I
UJ J
CO L J7 Z ZQ~~~ 2 WW Q UP CE CC U) J _J U) (n J J (n C3 Z Œn_ 02 U 2
Vibroseis Velocity Survey in Billie Yates 18D Well
Billie Yates 18D
Well location: (crossline, inline) 152, 112 Well location: (X, Y) 1867147, 557108
Kelly bushing elevation above mean sea level (MSL) Seismic reference datum (SRD) elevation above MSL Ground level elevation above MSL Velocity of medium from source -> surface sensor Velocity of medium from source -> SRD
Source Position Table
Source distance from wellhead Source elevation above MSL Source azimuth from north
These are three-component checkshot data There are 10 records, 3 traces per record Trace 1 = horizontal X-component Trace 2 = horizontal Y-component Trace 3 = vertical component
Trace Header Key Values
Bytes 1-4: Reel sequence number Bytes 13-16: Component flag (1 = horizontal X, 2 = horizontal Y, 3 = vertical) Bytes 41-44: Receiver depth (relative to kelly bushing) Bytes 105-108: First break time (ms) (picked by contractor)
Start time (ms): 0
End time: 3,000 Start trace: 1
End trace: 30
Input file: Number samples: 3,000 Format code: Bytes/sample: Float format: Bytes/trace: Sample rate: Length (ms):
1 (4 byte float) 4 IBM floating point 12,000 1 3,000
NOTE: End of file after sequential trace no. 30
33
Acknowledgments This work was funded by the U.S. Department
of Energy (contract no. DE-FG21-88MC25031) and Gas Research Institute (contract no. GRI-5093-212-2630) as a part of the Secondary Gas Recovery project. Additional funding was pro-vided by the State of Texas through the budget of the Bureau of Economic Geology. We thank Arch Petroleum, Enserch, and OXY USA, Inc., for allowing access to the study area and for provid-ing financial and technical support for the data collection and analysis. The 3-D seismic interpretation was done with software provided
by Landmark Graphics Corporation and work-station hardware provided by IBM Corporation. The 3-D seismic data were processed by Trend Technology, Midland, Texas.
Technical editing was by Tucker F. Hentz. Daniel D. Schultz-Ela reviewed the final draft. Figures were drafted by Randy Hitt, Susan Krepps, Joel L. Lardon, and Jana S. Robinson under the direction of Richard L. Dillon. Editing was by Susann Doenges. Word processing was by Susan Lloyd. Typesetting and design were by Margaret L. Evans.
References
Bureau of Economic Geology, 1995, The use of small, directionally focused charges as a 3-D seismic energy source: The University of Texas at Austin, Bureau of Economic Geology, technical summary of research conducted for the Gas Research Institute, U.S. Department of Energy, and State of Texas, GRI-94/0448, 10 p.
Galloway, W. E., 1989, Genetic stratigraphic sequences in basin analysis I: architecture and genesis of flooding-surface bounded depositional units: American Association of Petroleum Geologists Bulletin, v. 73, no. 2, p. 125-142.
Hardage, B. A., Carr, D. L., Finley, R. J., Lancaster, D. E., Elphick, R. Y., and Ballad, J. R., 1995, Secondary natural gas recovery: targeted applications for infield reserve growth in Midcontinent reservoirs, Boonsville field, Fort Worth Basin, Texas: The
University of Texas at Austin, Bureau of Economic Geology topical report prepared for the Gas Research Institute under contract no. 5093-212-2630 and the U.S. Department of Energy under contract no. DE-FG21-88MC25031, GRI-95 / 0454, two volumes variously paginated.
Lahti, V. R., and Huber, W. E, 1982, The Atoka Group (Pennsylvanian) of the Boonsville field area, North-Central Texas, in Martin, C. A., ed., Petroleum geology of the Fort Worth Basin and Bend Arch area: Dallas Geological Society, p. 377-399.
Thompson, D. M., 1982, Atoka Group (Lower to Middle Pennsylvanian), northern Fort Worth Basin, Texas: terrigenous depositional systems, diagenesis, and reservoir distribution and quality: The University of Texas at Austin, Bureau of Economic Geology Report of Investigations No. 125, 62 p.
34
Appendix
Loading the 3-D Seismic Data
The 3-D seismic data consist of 110 x 110 ft stacking bins. Trace (inline, X) values increase from west to east, and line (crossline, Y) values increase from south to north. The northeast corner of the survey is located at trace 206 and line 201, and the southwest corner is located at trace 74 and line 105. The longitude and latitude values for the four corners of the survey were translated to X and Y values for the North Central Texas Zone (4202) of the U.S. State Plane Coordinate System and the 1927 North American Datum. The following table describes the four corners of the 3-D public seismic data, starting in the southwest corner and going clockwise:
Trace Line Longitude Latitude X Location Y Location
74 105 -97.94162 33.17897 1864886 550461
74 201 -97.94132 33.20800 1865021 561020
206 201 -97.89384 33.20766 1879540 560838
206 105 -97.89416 33.17863 1879406 550279
Data on the Floppy Disks
Two 3.5-inch disks are included in this publication. Each disk contains a self-extracting archive that can be copied to a hard drive and run as an executable file. The executable file for disk 1 is named SGRPUB1.EXE. The executable file for disk 2 is SGRPUB2.EXE. Approximately 12 megabytes of disk space will be used by these two files after they are run. There are 39 *.LAS files, 3 *.SGY files, and 5 *.TXT files on the two disks. The *.LAS files are digitized well log curves in "log ASCII," version 2.0, format for the 38 wells within the seismic grid. These log curves have been digitized at a depth increment of 0.5 ft, or 0.15 m. The *.SGY files are a far-offset VSP image, a zero-offset VSP image, and dynamite checkshot wiggle trace data written in SEGY format. The *.TXT files are text files describing the far-offset VSP image, the zero-offset VSP image, the checkshot data, the well log data base, and the engineering data base and are in tab-delimited text format.
35
Completion, Production, and Petrophysical Information
Table 4 contains completion, production, and petrophysical information on the Boonsville wells provided as part of this public data set. The following descriptions explain the data contained in the various columns of the spreadsheet.
API Number
The API well identification number assigned to the well is recorded in this field.
Operator
The operator of each well is recorded in this field.
Well Name
The name and number of each well is recorded in this column.
Total Depth (ft)
The total depth (in feet) recorded by the driller for each well is listed in this field.
Top Perfs (ft), Bottom Perfs (ft)
The top and bottom of the perforated interval (in feet) for individual completion zones are recorded in these fields.
Zone (BEG)
The stratigraphic reservoir sequence in which a particular completion occurs is listed in this column. The sequence nomenclature for this project was developed by the Bureau of Economic Geology. Sequences that may be listed in this column include U Caddo (Upper Caddo), L Caddo (Lower Caddo), Davis, Trinity, Bridgeport, U Runaway (Upper Runaway), L Runaway (Lower Runaway), Beans Cr (Beans Creek), 4 Jasper Cr (4th Jasper Creek), U Jasper Cr (Upper Jasper Creek), M Jasper Cr (Middle Jasper Creek), L Jasper Cr (Lower Jasper Creek), and Vineyard.
The terms Caddo, Bend, Caddo/Bend, and Strawn may also appear in this column. If both Upper and Lower Caddo intervals are completed in a well, the Caddo designation is a combination of both completion intervals. This is because production from both Upper and Lower Caddo perforations is usually commingled and cannot be separated into Upper and Lower Caddo completions. Thus, the production information is reported
36
for the combined Caddo interval. Again, the Caddo designation does not indicate a unique or separate completion but rather a combination of Upper and Lower Caddo zones.
Likewise, the term Bend is used to refer to the combination of all completion intervals from the Wizard Wells through the Vineyard. The entire Bend Conglomerate section is considered a common source of supply, and production from multiple completion intervals is often commingled. Thus, the production information is often reported for the combined Bend interval. Again, the Bend designation does not indicate a unique or separate completion but rather a combination of Bend Conglomerate zones.
The term Caddo/Bend is used to summarize production information from all zones, from the Upper Caddo through the Vineyard, that may have completed in a particular well. Where possible, the combined production from all zones that have produced in a particular well is summarized here. In some wells, production from all zones from the Upper Caddo through the Vineyard may now be commingled.
The Strawn is the interval immediately above the Bend Conglomerate section, and information about the Strawn is not a part of this public data base. However, some Bend Conglomerate wells are later recompleted in the shallower Strawn. Whenever such a recompletion occurred for any of the 38 wells described in table 4, the production data from the Strawn appear in the table.
Initial or Recomplete
This field designates whether a particular perforation interval was part of the initial well completion or whether these perforations were added at some later date as part of a recompletion operation.
Type (Oil/Gas?)
This field designates whether a particular perforation interval was primarily oil or gas productive. The Caddo completion intervals are primarily oil productive throughout the project area. The Wizard Wells throughVineyard sequences are usually gas productive, although some of these intervals produce oil in the eastern portion of the project area, as seen in this data set.
Date of First Production
The date of first production on a sustained basis from a particular completion interval is recorded here. For zones that were tested, but never produced (NP), the date entered in this field is the date these intervals were perforated and tested.
Cum Gas (MMscf)
This is the cumulative gas production from a particular interval or group of commingled intervals in MMscf (million standard cubic feet).
37
Cum Oil (MSTB)
This is the cumulative oil production from a particular interval or group of commingled intervals in MSTB (thousand stock-tank barrels).
Cum Water (Mbbl)
This is the cumulative water production from a particular interval or group of commingled intervals in Mbbl (thousand barrels).
Cum As of Date
This is the date that corresponds to the cumulative gas, oil, and water production figures in the three previous fields. This date may vary from well to well and even among particular completion intervals within a given well. Often production from a completion zone that produced separately for several years will subsequently be commingled with production from zones added on recompletion. When possible, production attributed solely to this interval prior to commingling will be reflected in the three previous fields, and the last date of isolated production prior to commingling will be recorded here.
Current Status
This field designates the current status of a completion interval. It may be actively producing (P) isolated from other intervals, producing commingled (CO) with other intervals, shut in and temporarily abandoned (SI/TA), or abandoned (A) and no longer producing. Other designations include never produced (NP) for perforations that were tested but subsequently not produced, water injection well (WIW) for several Caddo wells that have been converted to water injection as part of a waterflood project, and drilled and abandoned (DA) for wells in the project area that were drilled and abandoned immediately as "dry" holes at the time of drilling, despite testing hydrocarbon potential in one or more of these wells.
Init. Pres. (psia)
This field designates the best estimate of initial reservoir pressure in psia (pounds per square inch, absolute), when available, for a particular completion interval. Initial pressure data are scarce throughout the project area and come from sources including drillstem tests, repeat formation tests, pressure buildup tests, and public data sources. When possible, initial pressure estimates are provided for individual completion intervals. Sometimes, initial pressure is measured only for a group of commingled intervals; in these cases, the initial pressure will be recorded in the Bend or Caddo summary fields.
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Field
Most of the gas production from these wells is part of the Boonsville Bend Conglomerate Gas (BBCG) field. This was the primary field of interest in the project area. The oil production and some of the gas production are part of several different field designations, however, and these are recorded here.
Zone (BEG)
This column is repeated here for reference purposes and for ease in viewing the log analysis results presented in the columns to the right. Only the specific completion intervals are listed in this column; there are no summary designations like Caddo, Bend, or Caddo/Bend. The log analysis results in the next five columns to the right were generated by Scientific Software-Intercomp, Inc. (SSI), and reflect SSI's final summations.
Gross Thick (ft)
This is the gross thickness (in feet) of the particular genetic stratigraphic sequence designated by the Bureau of Economic Geology.
When a dash (-) appears in this column or any of the next four columns, it means that the values for that sequence are given in another line. For example, there may be two Trinity intervals completed, but the log analysis results for the Trinity sequence as a whole are summarized the first time a Trinity completion is indicated in a particular well.
Net Pay (ft)
This is the net pay thickness (in feet) computed from SSI's log analysis for the particular reservoir sequence. To compute net pay, a porosity cutoff of 4 percent, a water saturation cutoff of 60 percent, and a shale volume cutoff of 50 percent were used.
Porosity (%)
This is the porosity (in percent) computed from SSI's log analysis for the particular reservoir sequence.
Water Sat (%)
This is the water saturation (in percent) computed from SSI's log analysis for the particular reservoir sequence.
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Net Hydro (ft)
This is the total net hydrocarbon feet computed from SSI's log analysis for the particular reservoir sequence. This value is calculated by multiplying net pay times porosity times (1 minus the water saturation), with both porosity and water saturation expressed as decimal fractions.
Remarks
This field includes any relevant comments about a particular completion interval or intervals.