USA Marine
ALASKA
Bering Sea
This marine gravity survey was recorded in the Bering Sea between May 15th, 1971 and October 15th, 1971 by Geosource, later acquired by Western Geophysical and then purchased by Austin Exploration Inc.
The area was divided into a series of units to provide flexibility in the selection of data.
The grid patterns are varied with about 10 x 15 miles in the Kodiak Island area and east, 25 x 25 miles from Kodiak Island west to Dutch Harbor, 50 x 50 miles in the Bering Sea, and 25 x 25 miles in the Chukchi Sea.
Doppler Sonar was used to provide continuous readings of the ship’s location between satellite derived positions.The gravity data were recorded in analog and digital form, using a LaCoste & Romberg Air/Sea Gravity Meter.
A density of 2.03 gm/cm³ was used for the sea floor to make the Bouguer correction.The data to be furnished includes a Bathymetry Map, Free-Air Gravity Map, Bouguer Gravity Map, Gravity Derivative Map and a magnetic tape; maps are at a scale of 1:250,000.
This survey consists of 26,966 miles of gravity data.
Chukchi Sea
This marine gravity and magnetics survey was recorded in the Chukchi Sea during the years 1980, 1981, 1982 and 1983.
Mileage: 10,957 miles Marine Gravity and 6,165 miles Marine Magnetics
Instrumentation: LaCoste & Romberg Gravity Meter and Geometrics Proton Magnetometer.
Navigation: Loran/doppler sonar/satellite
Deliverables: Bouguer anomaly maps at a scale of 1:250,000 and Bathymetry maps at a scale of 1:250,000 and Total Magnetic Intensity maps at a scale of 1:250,000
Hope Basin
The following data were taken from marine gravity and magnetic data that were purchased from Western Geophysical, including that recorded by Petty-Ray Geophysical and GSI. During 1981, a LaCoste & Romberg Gravity Meter was used in acquiring marine gravity data in the Hope Basin, Alaska.
Mileage: 1,344 miles Marine Gravity
Delivery Items: Bouguer Gravity Anomaly Map at a Scale of 1:250,000 and Water Depth
Map at a Scale of 1:250,000
Optional Items: Free-Air Gravity Anomaly Map at a Scale of 1:250,000 and Interpretation
Map at a Scale of 1:250,000, Written Report and Digital Data.
Beaufort Sea
The following data were taken from marine gravity and magnetic data that were purchased from Western Geophysical, including that recorded by Petty-Ray Geophysical and GSI.
During 1981, a LaCoste & Romberg Gravity Meter was used in acquiring marine gravity data in the Beaufort Sea, Alaska.
Mileage: 922 miles Marine Gravity
Delivery Items: Bouguer Gravity Anomaly Map at a Scale of 1:250,000 and Water
Depth Map at a Scale of 1:250,000
Optional Items: Free-Air Gravity Anomaly Map at a Scale of 1:250,000 and Digital Data.
Bristol Bay
The following data were taken from marine gravity and magnetic data that were purchased from Western Geophysical, including that recorded by Petty-Ray Geophysical and GSI.
During 1979 and 1982, a LaCoste & Romberg Gravity Meter was used in acquiring marine gravity data in the Bristol Bay of Alaska.
Mileage: 1,030 miles Marine Gravity
Delivery Items: Digital Data
Shelikof Strait
The following data were taken from marine gravity and magnetic data that were purchased from Western Geophysical, including that recorded by Petty-Ray Geophysical and GSI.
During 1979, 1981, 1982 and 1983, a LaCoste & Romberg Gravity Meter and Geometrics Proton Magnetometer were used in acquiring data in the Shelikof Strait of Alaska.
Mileage: 3,598 miles Marine Gravity and 2,472 miles Marine Magnetics
Delivery Items: Bouguer Gravity Map at a Scale of 1:100,000 and Water Depth Map at a Scale of 1:100,000
Optional Items: Second Derivative Gravity Map
St. George Basin
The following data were taken from marine gravity and magnetic data that was purchased from Western Geophysical, including that recorded by Petty-Ray Geophysical and GSI.
During 1980, 1981 and 1982, a LaCoste & Romberg Gravity Meter and Geometrics Proton Magnetometer were used in acquiring data in the St. George Basin of Alaska.
Mileage: 11,641 miles Marine Gravity and 6,052 miles Marine Magnetics
Delivery Items: Bouguer Gravity Map at a Scale of 1:96,000 and Water Depth Map at a Scale of 1:96,000
Optional Items: Digital Data , Free-Air Anomaly Map at a Scale of 1:96,000 and Composite Map at a Scale of 1:250,000 and Integrated Interpretation (Maps/Written Report)
Southeast Platform
The following data were taken from marine gravity and magnetic data that was purchased from Western Geophysical, including that recorded by Petty-Ray Geophysical and GSI.
During 1982, a LaCoste & Romberg Gravity Meter and Geometrics Proton Magnetometer were used in acquiring data in the Southeast Platform area, offshore Alaska.
Mileage: 996 miles of Marine Gravity and 996 miles of Marine Magnetic
Delivery Items: Bouguer Gravity Map at a Scale of 1:250,000 and Water Depth Map at a Scale of 1:250,000 and Total Magnetic Intensity Map at a Scale of 1:250,000
Optional Items: Digital data.
Fairweather Area
The following data were taken from marine gravity and magnetic data that was purchased from Western Geophysical, including that recorded by Petty-Ray Geophysical and GSI.
During 1979, a LaCoste & Romberg Gravity Meter and Geometrics Proton Magnetometer were used in acquiring data in the Fairweather area, offshore Alaska.
Mileage: 2946 miles of Marine Gravity and 2942 miles of Marine Magnetics
Delivery Items: Bouguer Gravity Map at a Scale of 1:96,000 and Total Magnetic Intensity Map at a Scale of 1:96,000
Optional Items: Digital data.
Norton Basin
The following data were taken from marine gravity and magnetic data that was purchased from Western Geophysical, including that recorded by Petty-Ray Geophysical and GSI.
During 1977, 1979, 1980, and 1982; a LaCoste & Romberg Gravity Meter and Geometrics Proton Magnetometer were used in acquiring data in the Norton Basin area, offshore Alaska.
Mileage: 11,851 miles of Marine Gravity and 5,595 miles of Marine Magnetics
Delivery Items: Bouguer Gravity Map at Scales of 1:96,000 or 1:100,000 and Water Depth Map at a Scale of 1:96,000 and Total Magnetic Intensity Map at Scales of 1:96,000 or 1:100,000
Optional Items: Free-Air Anomaly Map at a Scale of 1:96,000 , Second Derivative Map at a Scale of 1:96,000 and Digital Data
Navarin Basin
The following data were taken from marine gravity and magnetic data that was purchased from Western Geophysical, including that recorded by Petty-Ray Geophysical and GSI.
During 1978, 1980, 1981, and 1982; a LaCoste & Romberg Gravity Meter and Geometrics Proton Magnetometer were used in acquiring data in the Navarin Basin area, offshore Alaska.
Mileage: 18,100 miles of Marine Gravity and 17,480 miles of Marine Magnetics
Delivery Items: Bouguer Gravity Map at a Scale of 1:96,000 and Water Depth Map at a Scale of 1:96,000 and Total Magnetic Intensity Map at a Scale of 1:96,000
Optional Items: Free-Air Anomaly Map at a Scale of 1:96,000, Derivative Map at a Scale of 1:96,000 , Composite Map at a Scale of 1:250,000, Interpretation Map at a Scale of 1:96,000, Written Report and Digital Data
North Aleutian Shelf
The following data were taken from marine gravity and magnetic data that was purchased from Western Geophysical, including that recorded by Petty-Ray Geophysical and GSI.
During 1981 and 1983, a LaCoste & Romberg Gravity Meter and Geometrics Proton Magnetometer were used in acquiring data in the North Aleutian Shelf area, offshore Alaska.
Mileage: 14,208 miles of Marine Gravity and 13,050 miles of Marine Magnetics
Delivery Items: Bouguer Gravity Map at a Scale of 1:96,000 and Water Depth Map at a Scale of 1:96,000 and Total Magnetic Intensity Map at a Scale of 1:96,000
Optional Items: Free-Air Anomaly Map, Composite Map at a Scale of 1:250,000, Interpretation Map, Written Report and Digital Data
CALIFORNIA
Offshore California surveys include the Santa Maria Basin, the Santa Cruz – San Nicolas Basin, the San Clemente – San Diego Basin, and also the Point arena, Bodega, and Outer Santa Cruz Basins.
The basins are located on the Coast Range Province of Southern California and bounded on the east by the mountain ranges of the North American Cordillera. Most Cenozoic formations are present with the Miocene and Pliocene sediments having the most thickness and oil potential. The oldest rocks consist of metamorphosed sedimentary and volcanic rocks of the Franciscan formation of Jurassic to Early Cretaceous age. These data were recorded with a LaCoste & Romberg Air/Sea Gravity Meter for all surveys and these data are on magnetic tape.
Santa Maria Basin – Gravity Survey
Principal lines N-NE with 2 mile spacing; Tie lines NW-SE with 5 mile spacing; Map Scale 1 inch = 8000 feet; Size 1685 miles and 6000 square miles.
Available Products: Bathymetric Map , Free-Air Gravity Map , Bouguer Gravity Map with 3D terrain corrections , Total Magnetic Intensity Map , Report describing results of the survey and Cd Rom containing along line digital data.
Santa Cruz – San Nicolas Basin – Gravity & Magnetic Survey
Principal lines NE-SW with 1.5 mile spacing; Tie lines NW-SE with 5 mile spacing; Map Scale 1 inch = 4000 feet; Size 9543.6 miles and 10,400 square miles.
Available Products: Bathymetric Map, Free-Air Gravity Map, Bouguer Gravity Map with 3D terrain corrections, Total Magnetic Intensity Map, Report describing results of the survey and Cd Rom containing along line digital data.
San Clemente – San Diego Basin – Gravity & Magnetic Survey
Principal lines NE-SW with 1 mile spacing; Tie lines NW-SE with 4 mile spacing; Map Scale 1 inch = 4000 feet; Size 2320 miles and 1750 square miles.
Available Products: Bathymetric Map , Free-Air Gravity Map , Bouguer Gravity Map with 3D terrain corrections , Total Magnetic Intensity Map , Report describing results of the survey and Cd Rom containing along line digital data.
Offshore California – Gravity Survey
Principal lines E-W with 6 mile spacing; Tie lines NE-SW with 24 mile spacing. Map scale 1:250,000. Size 13,000 miles and 88,000 square miles.
Available Products: Bathymetric Map , Free-Air Gravity Map , Bouguer Gravity Map with 3D terrain corrections , Total Magnetic Intensity Map , Report describing results of the survey and Cd Rom containing along line digital data.
GULF OF MEXICO
The East Break Survey Area
Austin Exploration has completed the compilation of approximately 4000 miles of gravity and magnetic data in the East Breaks area, offshore Texas. This was recorded with a 60 fold seismic project by GECO U.S. Gravity, magnetic and bathymetry data are available in profile form at the same horizontal scale as the seismic sections.
The Bouguer Gravity and Total Magnetic Intensity Maps are available at the scale of 1 inch = 8000 feet. We have computed a Residual Gravity Map by removing a regional gravity gradient from the Bouguer Gravity and a second Vertical Derivative Gravity Map. These maps accentuate the gravity anomalies that are meaningful to hydrocarbon accumulation. We have calculated and contoured depths to the basement from the magnetic data. The resultant Magnetic Basement Map is contoured in 1000 foot intervals. The interpretive maps are at a scale of 1 inch = 8000 feet.
Specifications: Surveyed: 1984 with a LaCoste & Romberg Air/Sea Gravity Meter and a Geometrics Proton Precision Magnetometer.
Navigation: The traverses were positioned using STARFIX.
Data: The gravity, magnetics and bathymetry data were recorded digitally and are available.
Principal lines of the survey: NW-SE and N-S with 1.25 mile spacing; E-W with 2.5 mile spacing.
Tie line spacing : NE-SW with 2.5 mile spacing and N-S with 5 mile spacing.
Map Scale : 1 inch = 8000 feet.
Size: Approximately 4000 miles.
The Green Canyon – High Resolution Gravity Survey Area
We are happy to announce the availability of 180 blocks of high resolution gravity data acquired in the Green Canyon area of the Gulf of Mexico. These data were acquired coincidentally with the Veritas DGC Green Canyon Phase III survey, aboard the M/V Polar Search. There are 72.8 kilometers of gravity data per block with track line spacing of 320 meters.
The gravity meter used on this survey is an upgraded LaCoste & Romberg meter using the ZLS Ultrasys™ digital acquisition and control system with 1 second recording.
Deliverables: Data Acquisition Report , Data Processing Report , CD-Rom containing along line digital data
Maps: Free-Air Gravity, Bouguer Gravity, Water Depth
Gulf of Mexico Ultra
High Resolution Gravity “ Ultra Survey”
We are pleased to announce the availability of 975 blocks of high resolution gravity data acquired coincidentally with the Western Geophysical Ultra Survey. There are 72.44 miles of gravity data per block with track line spacing of 200 meters.
The gravity meter used was an upgraded LaCoste & Romberg meter with the L&R SEASYS™ digital acquisition and control system with 1 second recording.
Deliverables: Data Acquisition Report , Data Processing Report , CD-Rom containing along line digital data
Maps: Free-Air Gravity, Bouguer Gravity, Water Depth
Gravity and Magnetic Lloyd Ridge Survey
Austin Exploration recorded approximately 6000 miles of gravity and magnetic data in Lloyd Ridge, Gulf of Mexico on the M/V Digicon Explorer in 1988. Traverses are oriented NE-SW with a 4×4 mile grid.
The gravity data were recorded with a LaCoste & Romberg Air/Sea Gravity Meter. Magnetic data were recorded with a Geometrics Marine Proton Precession Magnetometer. GPS/STARFIX was the primary navigation system. A Furuno deep water fathometer was used for bathymetric control.
The data are compiled at the scale of 1 inch = 8000 feet with profiles at that scale and the scale of the seismic cross sections.
Available Deliverables: Bouguer Gravity Map with 3D terrain corrections, Total Magnetic Intensity Map, Bathymetric Map, Total Magnetic Intensity Reduced to the Pole, Second Vertical Derivative Map of the Gravity, Second Vertical Derivative Map of the Magnetics, Along line digital data on CD-Rom
The Probe Gravity and Magnetic Survey Area
Gravity and Magnetic data are available across the PROBE seismic survey conducted by Geosource, now Western Geophysical. There are approximately 25,000 miles of traverse in PROBE.
These data were recorded from 1977 to 1988 when traverses were in filled to complete a 2 x 2 mile grid in the Walker Ridge.
Operations: The Gravity data were recorded with a LaCoste & Romberg Air/Sea Gravity Meter with digital and analog recording systems. The magnetic data were recorded with a Geometrics Marine Proton Precession Magnetometer with digital and analog recorders. The primary navigation system was SPOT used with GPS. A deepwater fathometer was used for continuous bathymetric data.
Compilation and Results: (The compiled gravity maps are at the scale of 1:500,000 feet)
– Bouguer Gravity Map with 3Dl terrain corrections
– Total Magnetic Intensity Map
– Bathymetric Map
– CD-Rom containing along line digital data
– Gravity Derivative Map
The Walker Ridge High Resolution Gravity Survey Area
Austin Exploration is pleased to announce the availability of high resolution gravity data acquired in the Walker Ridge area of the Gulf of Mexico coincidentally with the Veritas DGC Walker Ridge Phase I & II. 72.8 kilometers of gravity data were acquired per block with 320 meter track line spacing. These data were acquired onboard the M/V Polar Search and the M/V Polar Princess.
The gravity meters used on both vessels were digitally upgraded LaCoste & Romberg meters with 1 second recording.
Deliverables: Data Acquisition Report , Data Processing Report , Digital along line data on a CD-Rom
Maps: Free-Air Gravity, Bouguer Gravity, Water Depth
The Large Gulf of Mexico Survey Area
Austin Exploration has conducted a study of approximately 100,000 miles of gravity data that were recorded in the Gulf of Mexico by the Geophysical and Solar Terrestrial Data Center. Traverses are predominantly east-west and spaced about 8 miles apart. Tie lines are between 15 and 50 miles apart.
The gravity maps essentially represent a density distribution in the salt structure provinces with maximum gravity trends corresponding with thick sediments or depocenters. Minimum gravity trends correlate with thick salt masses. More local minima, responding to salt diapers, are mapped within the gradient between the maximum and minimum trends and in the maximum trends. Low density shale trends along the northwest portion of the Gulf are exhibited as minimum gravity anomalies. A major rift zone is indicated by a strong maximum and minimum gravity trend in the northeast and eastern portion of the Gulf. Reefing is suggested along the maximum trend that is generally located along the continental slope, offshore Florida. It is believed that the gravity data are very useful in evaluating the hydrocarbons potential of the Gulf of Mexico.
Specifications:
The Bouguer Gravity Map and Residual Gravity Map are on a base showing the offshore blocks. These maps are on three sheets at the scale of 1:500,000 and on a composite at the scale of 1:1,000,000. The regional gravity, traverse locations, and a series of north-south profiles showing the Bouguer and regional gravity are posted on maps scaled at 1:1,000,000.
The Integrated Mississippi Canyon Area
We recently integrated the marine gravity and magnetic data from the Louisiana Continental Slope Survey, conducted by GAI-GMX in 1969, with that from the Mississippi Canyon Survey recorded by Austin Exploration along with the Jebco Seismic Survey in 1984. Both surveys have very good repeat accuracy at line intersections.
The data from the LaConSlope has a line spacing of 1 x 5 miles and the Mississippi Canyon data are spaced 2×4 miles. The enclosed grid shows the combined control, believed to be the tightest gravity and magnetic grid in this area at about 1 x 2.7 miles. The combined data set includes about 7000 miles of data.
The above gravity and magnetics are of sufficient accuracy to aid in the interpretation of the salt structure, including vertical and horizontal movement. If the top of a salt flow is mapped by the seismic data and there is sufficient density contrast between the salt and the sediments, the bottom of the salt can be modeled with our data. Where the top and bottom of the salt in the section is defined by the seismic and does not account for all the minimum gravity and magnetic anomalies, salt structure below the tabular salt originating from Mother salt can be modeled. Subsalt sedimentary anticlines are mapped as maximum gravity anomalies and can be further substantiated with the magnetics if the basement is also uplifted.
The Offshore Louisiana – Garden Banks Survey Area
Austin Exploration recorded a marine gravity data survey in the Garden Banks area. These data were recorded with our LaCoste & Romberg Air/Sea Gravity Meter No. 101.
The standard corrections have been applied and the traverses merged at the intersections. The average mistie was only 0.45 milligals. The data are available on magnetic tape.
The salt domes in this area cause significant gravity anomalies.
USA LAND
Arkansas Ouachita Trend Belt Gravity Survey
Gravity is an effective tool in the study of the complex Arkansas Ouachita Trend Belt.
There is a major density contrast between the Arkansas Novaculite and the overlying Stanley Shale.
Anticlines in the novaculite, like that at the Isom Springs Field in Marshall County, Oklahoma, cause strong maximum gravity anomalies.
Another strong density contrast is between the Arbuckle formation and the overlying flysch deposits. Large suspected carbonate buildups in the Arbuckle into the flysch sediments would cause prominent maximum gravity anomalies.
Large reefs are expected along a broad carbonate trend projected from Texas to cross the gravity survey.
In addition, there are many intrusives evident from the gravity.
Specifications:
– The plat shows the number of stations by 30 minute quadrangles.
– Bouguer Gravity Maps and a digital tape are available.
– Residual gravity data are available for the quadrangles.
Gravity Survey Along the Ouachita Trend Belt in S.E. Oklahoma & N.E. Texas
Gravity is an effective tool in the study of the complex Ouachita Trend Belt.
There is a major density contrast between the Arkansas Novaculite and the overlying Stanley Shale.
Anticlines in the novaculite, like that at the Isom Springs Field in Marshall County, Oklahoma, cause strong maximum gravity anomalies.
Another strong density contrast is between the Arbuckle formation and the overlying flysch deposits. Uplifts in the Arbuckle into the flysch sediments would cause prominent maximum gravity anomalies.
Specifications:
The gravity control was recorded using high standards of quality. The new coverage in the area was integrated with previous control to provide a suitable grid. Gravity values are accurate to approximately 0.04 milligals.
The gravity coverage, including about 19,000 stations, may be purchased, with a minimum purchase of 1000 stations in a contiguous block.
The Mississippi Ouachita Trend Belt Gravity Survey
Austin Exploration acquired and compiled a detailed gravity survey along the Ouachita Trend in Mississippi.
There is a strong density contrast between the clastic section above the Devonian and the carbonate section below. This allows precise delineation of the structure in the lower Paleozoic by the gravity method.
The regional structure can be seen from the gravity, including the union of the Ouachita Trough and the Appalachian Basin, at right angles, south of the Black Warrior Basin.
Local anticlines, faults and synclines are also mapped in detail by the gravity.
Specifications:
– The data were recorded using high standards of accuracy.
– The maximum elevation difference at tie points was less than one foot and this was prorated down the traverses.
– The gravity data are accurate to less than 0.05 milligals.
– The plat shows the number of stations by 30 minute quadrangles.
– Bouguer Gravity Maps are provided.
– Residual Gravity Maps that are appropriate for the area data are available for the quadrangles.
A Detailed Gravity Survey Along S.W. Appalachian Overthrust Trend
Austin Exploration announces the availability of gravity data in the southwestern Appalachian Overthrust Trend.
Gravity information is very effective in defining structure in the Paleozoic section, both on and off the onlapping Mesozoic sediments.
The coverage offered is in sufficient detail to delineate anticlines and faults and can be used in the acquisition of acreage.
The gravity control was recorded by Austin Exploration using high standards of quality.
The new coverage was integrated with previously recorded data in Area 1.
Austin recorded the data in Area 5 earlier with accuracies equivalent to our present work.
Values are accurate to approximately 0.05 milligals.
Columbia River Plateau of Oregon Gravity Survey
Austin Exploration has completed a gravity survey in the Columbia River Plateau of Central Oregon.
New gravity stations were integrated with previous data to provide appropriate control for the area.
All data were digitized and a comprehensive correction for the terrain computed.
Gravity information is most useful in resolving the complex structural conditions in this area.
The region is covered with basalt that makes seismic exploration difficult.
The basalt has a higher density than the underlying sediments and makes gravity information particularly effective in defining areas of thin basalt and thick sedimentary section.
Basement structure contrasts in density with the overlying sediments and causes gravity anomalies.
Specifications:
– Bouguer gravity and Residual gravity data are available for purchase.
Gravity Survey of the Cordilleran Hingeline Thrust Belt in Utah
The Cordilleran Hingeline transects central Utah from the north central part of Utah to the southwest corner of the State.
The hinge area between the shelf and miogeosyncline of the Cordilleran geosyncline controlled deposition and erosion of sediments ranging in age from Cambrian through Early Triassic.
Facies changes occur in the Paleozoic and early Mesozoic. Superimposed on the stratigraphic changes are the major thrusts of the Sevier and Laramide orogenies.
Structures similar to those along the thrusts in northern Utah and southwestern Wyoming exist along the leading edges of the thrusts in the Hingeline area.
The gravity method works very well in this area due to a major increase in the density of the sediments, between the overlying Mesozoic and the underlying Triassic and Paleozoic section.
The gravity control was acquired using high standards of accuracy for the surveying and the recording of gravity.
Elevation loops tied within a maximum of one foot, which was then prorated out. Gravity values are accurate to approximately 0.04 milligals. A suitable grid of data was accomplished.
There are over 23,000 gravity stations in the central Utah portion.
Area A contains about 3346 gravity stations and Area B consists of about 3594 gravity stations.
Northern Columbia River Plateau Survey in Washington
Austin Exploration has acquired gravity coverage in the Northern Columbia River Plateau area of Washington.
This coverage is part of a nonexclusive magnetotelluric/gravity package offered by Advanced Energy Technology Inc. and Austin Exploration. The gravity data are now available separately.
The data grid has an approximate 3×3 mile loop covering 9,000 square miles.
All field operations were supervised by a Potential Field Geophysicist to provide quality control of the data acquisition.
The position accuracy is less than 50 feet horizontal and one foot vertical.
The gravity values have an accuracy of less than 0.05 milligals.
The region is covered with basalt that makes seismic exploration difficult. The basalt is higher density than the underlying sediments and makes gravity information effective in defining areas of thin basalt and thick sedimentary section.
Basement structure contrasts in density with the overlying sediments and causes gravity anomalies. Magnetotelluric data responds to the above conditions and has also been used successfully in the Columbia River Plateau.
Specifications:
– The plat (above) shows the outline of the survey area.
– There are 20,266 gravity stations.
Gravity Survey of Southeastern Mississippi
Austin Exploration, Inc. has completed a large gravity study in southeastern Mississippi as outlined in the map above.
The gravity method is very effective in the delineation of salt structure. The density of the salt contrasts sharply with the density of the sediments, producing strong gravity anomalies.
This information, integrated with geologic data, makes it possible to map the salt structure and predict the favorable positions on the salt flanks for production from the Norphlet, Smackover and Haynesville formations.