U.S. GEOLOGICAL SURVEY DIGITAL DATA SERIES DDS-5
National Energy Research Seismic Library -- Processed Seismic
Data for 29 Lines in the National Petroleum Reserve in Alaska
DATA BASE DOCUMENTATION
INTRODUCTION
This disc contains (1) processed seismic data for 29 lines in
the NPRA, (2) seismic line location map image files and text
files of side panel information for those lines, and (3) a data
base of supporting text information built using the Borland
International PARADOX data base management system. Table 1 is a
list of the seismic line identification, the fold of the data,
the field party number, the line miles per field party, and the
total line miles for the seismic lines on this disc (Tetra Tech,
1982).
SEISMIC DATA FILES
The seismic data for each seismic line on disc are contained
in nine different files having the seismic line identification as
the file name and the file suffix identifying the type of
information contained. Each seismic line was converted from SEGY format to a .VAL file, a .RMS file, and a .HDR file. The .VAL
file contains the seismic data traces. The .RMS file contains
the root mean square (RMS) amplitude value for each of those data
traces. Any tape header information that may have existed is
contained in the .HDR file. Side panel information, as is
displayed on final sections describing the processing history of
the data, is contained in a .SPN file. A shot point location map
for each line, displayed graphically with the seismic data by the
programs SEGMENT or SEGDB (see SEGMENT.DOC), is contained in a
parameters used by the programs SEGMENT or SEGDB in displaying
the data, and a .EPT, .VPT, and .XPT file used for EGA, VGA, and
extended VGA displays, respectively. Additionally, each seismic
line has location map image files .EMP (EGA) and .VMP (VGA).
These image files are used independently from the seismic display
by the program MAPPER (see MAPPER.DOC) from within the Display
and Report System (see DRS.DOC) and display the specified seismic
line highlighted within the seismic line grid as well as other
features such as well locations, streams, water bodies, roads,
etc. Table 2 summarizes each file type.
As an example, seismic line 107-77 was converted from SEG-Y to
107-77.VAL, 107-77.RMS, and 107-77.HDR. It also has files 10777.SPN, 107-77.MAP, 107-77.LBL, 107-77.EPT, 107-77.VPT, and 107-
77.XPT, as well as location map image files 107-77.EMP and 10777.VMP.
1
A utility program, SEGYDISK, allows the reconstruction of the
original SEG-Y data, which may then be uploaded to a seismic data
processing system (see SEGYDISK.DOC).
SUPPORTING DATA BASE SYSTEM
In addition to the actual seismic data and the associated
files discussed above, the disc also contains a data base of
seismic and well data built using the Borland International
PARADOX data base management system and consisting of a
collection of related data tables. Tables containing seismic
data are related to one another by the seismic line identifier.
Well data tables are related through the well American Petroleum
Institute (API) number, which uniquely identifies each well.
Included with the data base is an interactive, menu-driven
Display and Report System (DRS), which may be used to present the
data to the user's screen or printer or to a disk file.
Associated with each table are specific forms and reports used by
the DRS to present that information to the user. Users owning
the PARADOX data base management system may use the data tables
directly, as well as use the DRS. Those not owning PARADOX may
execute the DRS using the PARADOX Runtime System included.
Information on the DRS and the PARADOX Runtime System is
available in DRS.DOC. Table 3 is a list of the data base file
types and describes their function.
SEISMIC DATA BASE
The seismic data base consists of eight tables of data related
through the seismic line identification and an additional table
used for display purposes by the DRS. Table 4 is a list of the
data tables composing the seismic data base.
The table Disk1 represents an index of the seismic data
available on this disc. Table 5 displays the Disk1 table
structure. Users may display this table to obtain a listing of
available seismic lines, the starting and ending shot point
numbers for that line, the starting and ending latitudes and
longitudes, and the number of shot point locations for that line.
Table Sptlocs contains the shot point locations for a given
seismic line identifier. Each shot point has an associated
latitude and longitude in decimal degrees. Table 6 displays the
Sptlocs table structure. The shot point location data were
obtained from the National Geophysical Data Center (NGDC) of the
National Oceanic and Atmospheric Administration (NOAA, 1981a).
Table Vedindex represents an index to the available velocity
information for the seismic lines contained on this disc. Not
all seismic lines presented in this data set have associated
velocity information. Users may display this table to obtain a
listing of seismic lines having associated velocity information,
the starting and ending shot point number associated with
2
velocity functions for a given seismic line, as well as the
number of time, velocity, and depth records for that seismic
line. Table 7 is a display of the Vedindex table structure.
Table Vels contains the time, velocity, and depth (TVD) data
by shot point for a given seismic line for those lines collected
between 1974 and 1978. Table 8 displays the Vels table
structure. The TVD data presented were derived from TVD data
available through the NGDC (NOAA, 1981b). The TVD data obtained
from the NGDC contained the seismic line identification, the shot
point number of the velocity function, the latitude and longitude
for that shot point, and the two-way traveltimes in milliseconds,
the average velocities in feet per second, and depth in feet at
those times calculated by using the corresponding average
velocities. RMS and interval velocities were calculated by using
those data. The interval velocity given with the first time
value represents the interval velocity between time 0 and that
first time value. A sample comparison between the RMS values
calculated and those used by the contractor processing the data
yielded a difference of 10 percent or less.
Table Intersec contains the seismic line intersections for the
29 lines in the data set. The table contains the seismic line
identification of the intersected line and its shot point and the
identification of the intersecting line and its shot point.
Table 9 is a display of the Intersec table structure.
Table Field contains various field recording parameters for
the seismic lines in the data set obtained from the "Petroleum
Exploration of the NPRA, 1974 - 1981, Final Report" prepared by
Tetra Tech (1982). Table 10 is a display of the Field table
structure.
Table Tapes contains the USGS Tape Library information of all
processed tapes for the seismic lines in the data set. These
tapes were turned over to the USGS by Tetra Tech at the
conclusion of the NPRA project in 1982. Table 11 is a display of
the Tapes table structure.
Table Cdptable contains information allowing conversion
between data trace number, common depth point (CDP) number, and
shot point number. One can identify the sequential data trace
number by its corresponding CDP number and shot point number.
Table 12 is a display of the Cdptable table structure.
Table Cdpdummy is used by the DRS as a template for displaying
a combination of information contained in the Sptlocs and
Cdptable tables. Table 13 is a display of the Cdpdummy table
structure.
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WELLS DATA BASE
The wells data base contains information for 126 U.S.
Government wells within or near the NPRA (Bird, 1988). It
consists of three tables of data related through the well API
number and an additional table used for display purposes by the
Display and Report System. Table 14 is a list of the data tables
composing the wells data base.
Table Wellocs represents an index of the well data available
on disc. The Wellocs table contains the API number, the well
name, and the latitude and longitude in decimal degrees. Table
15 is a display of the Wellocs table structure. Users may
display this table to obtain an index of available well data.
Table Wellhist gives the well history for a given well. Each
well in the Wellhist table has an API number, the agency drilling
the well, the spud and completion dates, the well class, the
ground and kelly bushing elevations (in feet), and a general
description. Table 16 is a description of the well classes used.
Table 17 is a display of the Wellhist table structure.
Table Welldeps gives the depths to sixteen different rock
units, where they exist, measured from the kelly bushing and
rounded to the nearest 5 feet; the table also gives total well
depth. Table 18 is a list of the rock units selected. Table 19
is a display of the Welldeps table structure.
Table Wellsful is used by the DRS as a template for displaying
a combination of information contained in the Wellocs, Wellhist,
and Welldeps tables. Table 20 is a display of the Wellsful table
structure.
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REFERENCES
Bird, K.J., 1988, Alaskan North Slope stratigraphic nomenclature
and data summary for Government-drilled wells, in Gryc,
George, ed., Geology and exploration of the National
Petroleum Reserve in Alaska, 1974 to 1982: U.S. Geological
Survey Professional Paper 1399, p. 317-353.
National Oceanic and Atmospheric Administration, 1981a, National
Petroleum Reserve in Alaska (NPRA); Seismic reflection shot
points for 1972 - 1980: National Geophysical Data Center, Data
Set No. TGZ-0230-MT. [Available from National Geophysical Data
Center, E/GC, Dept. CNP, 325 Broadway, Boulder, Colorado
80303.]
----- 1981b, National Petroleum Reserve in Alaska (NPRA); Time,
velocity, and depth (TVD) information, 1972 - 1978: National
Geophysical Data Center, Data Set No. TGZ-0220-MT. [Available
from National Geophysical Data Center, E/GC, Dept. CNP, 325
Broadway, Boulder, Colorado 80303.]
Tetra Tech, Inc., 1982, Petroleum exploration of the NPRA, 19741981, final report: Houston, Texas, Tetra Tech, Inc., vol. I,
II, III, Rept. 8200, 183 p., 132 figs., 71 seismic maps.
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Table 1: Summary of seismic data on disc.
Line Number Fold Field Party
field party Total line miles
107-77
12
G1184
12
G1186
107XE-78
12
G1173
107XW-78
6
G1186
133-76
6
G182
133-77
6
G1186
25-74
6
G184
25X-75
6
G195
25X-77
6
G1173
26-74
6
G184
26-76
6
G186
26X-75
6
G184
43-75
6
G184
46-75
6
G184
47-75
6
G195
47X-78
6
G1184
47XS-79
24
G1184
61-75
6
G186
61-76
6
G182
6
G186
62-75
6
G182
6
G186
24-79
6
G1182
63-75
6
G182
6
G186
630-79
12
G1186
65-75
6
G186
71-75
6
G184
71-77
6
G1173
711-80
6
G1182
726-80
6
G1186
728-80
6
G1182
U5-78
12
G1173
Total milage:
Line miles per
45.3
35.7
33.9
17.3
38.0
33.0
31.2
25.5
34.4
79.3
81.3
42.3
50.5
70.5
94.8
63.9
18.2
13.8
16.8
72.0
41.5
14.8
9.5
33.8
87.5
48.0
14.5
18.8
20.3
10.3
26.2
15.7
25.3
81.0
33.9
17.3
38.0
33.0
31.2
25.5
34.4
79.3
81.3
42.3
50.5
70.5
94.8
63.9
18.2
13.8
88.8
56.3
9.5
121.3
48.0
14.5
18.8
20.3
10.3
26.2
15.7
25.3
1263.5
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Table 2: Seismic data file types.
File Suffix
.VAL
.RMS
.HDR
.MAP
.SPN
.LBL
.EPT
.VPT
.XPT
.EMP
.VMP
Format
Binary
Binary
Binary
Text
Text
Text
Binary
Binary
Binary
Binary
Binary
Description
Converted seismic traces.
RMS values for converted seismic traces.
Tape header information.
Shot point location map.
Side panel information.
Parameters for display software.
EGA display.
VGA display.
Extended VGA display.
EGA location map image.
VGA location map image.
Table 3: PARADOX data base file types.
File Suffix
.DB
.PX
.SET
.F{n}
.R{n}
File Type and Function
Database table containing the data.
Primary index created by PARADOX for the table.
Table characteristics, such as column widths.
Form associated with a given table. Form number
{n} may range from 1 to 15
Report associated with a given table. Report
number {n} may range from 1 to 15.
Table 4: Seismic data base data tables.
Table Name
Disk1
Sptlocs
Vedindex
Vels
Intersec
Field
Tapes
Cdptable
Cdpdummy
Description
Index of seismic lines contained in this data set.
Shot point locations of seismic lines in this data
set.
Index of velocity data contained in this data set.
Time/Velocity/Depth information by seismic line.
Seismic line intersections.
Seismic line field recording parameters.
USGS processed tape library information.
Sequential trace number to CDP to shot point
conversion information.
Template used for the display of Cdptable and
Sptlocs information.
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Table 5: Disk1 table structure.
Field Name
Lineid
Sp1
Lat1
Lon1
Sp2
Lat2
Lon2
Nspts
Field Type
A10
N
N
N
N
N
N
N
Description
Seismic line identification.
Starting shot point number.
Starting latitude, decimal degrees.
Starting longitude, decimal degrees.
Ending shot point number.
Ending latitude, decimal degrees.
Ending longitude, decimal degrees.
Number of shot points in data base.
Table 6: Sptlocs table structure.
Field Name
Lineid
Spt
Lat
Lon
Field Type
A10
N
N
N
Description
Seismic line identification.
Shot point number.
Latitude, decimal degrees.
Longitude, decimal degrees.
Table 7: Vedindex table structure.
Field Name
Lineid
Sp1
Lat1
Lon1
Sp2
Lat2
Lon2
Numrecs
Field Type
A10
N
N
N
N
N
N
N
Description
Seismic line identification.
Starting shot point number.
Starting latitude, decimal degrees.
Starting longitude, decimal degrees.
Ending shot point number.
Ending latitude, decimal degrees.
Ending longitude, decimal degrees.
Number of time, velocity, and depth
entries.
Table 8: Vels table structure.
Field Name
Lineid
Spt
Time
Vrms
Vint
Vavg
Depth
Field Type
A10
N
N
N
N
N
N
Description
Seismic line identification.
Shot point number.
Two-way traveltime, msec.
RMS velocity, ft/sec.
Interval velocity, ft/sec.
Average velocity, ft/sec.
Depth, ft.
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Table 9: Intersec table structure.
Field Name
Lineid
Spt
Interid
Interspt
Field Type
A10
N
A10
N
Description
Seismic line identification.
Shot point number.
Intersecting seismic line
identification.
Intersecting seismic line shot point.
Table 10: Field table structure.
Field Name
Lineid
Party
LineMiles
Source
SpVpRange
NumChans
Fold
GrpInt
Spread
Geophones
SampRate
RecLen
SpVpSpace
VibrPt
VibrNumX
VibrPatch
Filter
SpOffset
Charge
Depth
Field Type
A10
A10
N
A10
A13
N
N
N
A10
N
N
N
N
N
A6
N
A7
N
N
N
Description
Seismic line identification.
Survey party identification.
Number of line miles recorded.
Energy source type.
Shot point/vibroseis point range.
Number of channels recorded.
Multiplicity of data recorded.
Group interval, ft.
Spread, symmetrical, ft.
Number of geophones per group.
Recording sample rate, ms.
Recording record length, ms.
Shot point/vibroseis spacing, ft.
Vibroseis point.
Vibroseis separation, in-line, ft.
Vibroseis location patch, in-line, ft.
Field recording filter, Hz.
Shot point offset, ft.
Dynamite charge, lbs.
Dynamite charge depth, ft.
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Table 11: Tapes table structure.
Field Name
Lineid
Slot
Reel
Year
Setname
Type
Format
Density
Proccomputer
Medium
Reclength
Samplerate
Numchans
Spts
Files
Fold
Field Type
A10
N
A20
N
A16
A20
A15
A10
A15
A8
N
N
N
A11
A11
N
Description
Seismic line identification.
Tape library slot number.
Tape reel number.
Year collected.
Data set name.
Data type.
Data format.
Recording density.
Processing computer.
Recording medium.
Record length, ms.
Sample rate, ms.
Number of channels.
Shot point range.
Files range.
Multiplicity.
Table 12: Cdptable table structure.
Field Name
Lineid
Spt
Trace
Cdp
Field Type
A10
N
N
N
Description
Seismic line identification.
Shot point number.
Sequential trace number.
Common depth point number.
Table 13: Cdpdummy table structure.
Field Name
Lineid
Spt
Trace
Cdp
Lat
Lon
Field Type
A10
N
N
N
N
N
Description
Seismic length identification.
Shot point number.
Sequential trace number.
CDP number.
Shot point latitude.
Shot point longitude.
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Table 14: Wells data base data tables.
Table Name
Wellocs
Wellhist
Welldeps
Wellful
Description
Index of wells contained in this data set.
Well histories of wells in this data set.
Depths to selected rock units.
Template used for a full display of well
information.
Table 15: Wellocs table structure.
Field Name
API
Name
Lat
Lon
Field Type
A12
A25
N
N
Description
Well API number.
Well name.
Latitude, decimal degrees.
Longitude, decimal degrees.
Table 16: Well classes used.
Class
DA-0
DA-1
DA-2
DA-0
DA-1
DA-2
DA-3
AP-1
AP-2
AP-4
AP-5
P-2
P-3
P-4
P-5
SP-1
Description
Dry, no shows, abandoned.
Dry, oil shows, abandoned.
Dry, gas shows, abandcription
Dry, no shows, abandoned.
Dry, oil shows, abandoned.
Dry, gas shows, abandoned.
Dry, oil and gas shows, abandoned.
Producing, oil, abandoned.
Producing, gas, abandoned.
Producing, oil with gas shows, abandoned.
Producing, gas with oil shows, abandoned.
Producing, gas.
Producing, oil and gas.
Producing, oil with gas shows.
Producing, gas with oil shows.
Producing, oil, suspended.
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Table 17: Wellhist table structure.
Field Name
API
Agency
Spud
Completed
Class
Grnd
KB
Descrip
Field Type
A12
A4
D
D
A4
N
N
A80
Description
Well API number.
Agency drilling well.
Spud date, mm/dd/yy.
Completion date, mm/dd/yy.
Well class.
Ground elevation, ft.
Kelly bushing elevation, ft.
Description.
Table 18: Rock units selected.
Designation
T1
T2
T3
T4
T5
T6
T7
T8
T9
T10
T11
T12
T13
T14
T15
T16
Rock Unit
Surficial deposits and/or Gubik Formation.
Sandstone of the Colville Group and Sagavanirktok
Formation, undivided.
Shale of the Colville Group.
Nanushuk Group.
Torok Formation.
Pebble shale unit.
Kingak Shale.
Sag River Sandstone.
Shublik Formation.
Fire Creek Siltstone Member of the Ivishak
Formation, Sadlerochit Group.
Ledge Sandstone Member of the Ivishak Formation,
Sadlerochit Group.
Kavik Member of the Ivishak Formation, Sadlerochit
Group.
Echooka Formation, Sadlerochit Group.
Lisburne Group.
Endicott Group.
Basement complex.
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Table 19: Welldeps table structure.
Field Name
API
Total
T1
T2
T3
T4
T5
T6
T7
T8
T9
T10
T11
T12
T13
T14
T15
T16
Field Type
A12
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
Description
Well API number.
Total depth, ft.
Depth to top of rock units as
described
in Table 18, ft.
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Table 20: Wellsful table structure.
Field Name
API
Agency
Spud
Completed
Class
Grnd
KB
Descrip
Name
Lat
Lon
Total
T1
T2
T3
T4
T5
T6
T7
T8
T9
T10
T11
T12
T13
T14
T15
T16
Field Type
A12
A4
D
D
A4
N
N
A80
A25
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
Description
Well API number.
Agency drilling well.
Spud date, mm/dd/yy.
Completion date, mm/dd/yy.
Well class.
Ground elevation, ft.
Kelly bushing elevation, ft.
Description.
Well name.
Latitude, decimal degrees.
Longitude, decimal degrees.
Total depth, ft.
Depth to top of rock units as
described
in Table 18.
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