Principal facts for gravity data collected in the southern Albuquerque Basin area and a regional compilation, central New Mexico

The Geological Survey Center has conducted a seismic survey in the southern Natuna Sea region to obtain geological information below relating to the potential energy resources of the area. The area research is located in the western part and outside the Singkawang Basin area (BG, 2008), which is separated by a Metamorf ridge. 2D seismic survey results show 3 different rock units, namely shallow marine sedimentary rocks, tertiary sedimentary rocks and pre-Tertiary sedimentary rocks, with pre-Tertiary sediment depths of less than 2000 ms. Interpretation of seismic data shows the pattern of graben structures that form sub-basins. strong refl ectors seen in seismic record can distinguish pre-rift, syn-rift and post-rift deposits. There are 2 wells, namely Datuk 1X and Ambu 1X. Datuk 1X has a depth of 1187 meters, and The Ambu 1X has a depth of 880 meters that is crossed by a seismic line. Both drilling has obtained Tertiary aged sandstone that covers pre-Tertiary bedrock.Gravity anomaly data in the seismic region shows anomaly values between 10 to 54 mgal which form the anomaly ridge and basinThe ridge anomaly extends as an anticline, while the anomaly basin also rises to form a syncline. Sincline and anticline trending southwest - southeast, with widening and narrowing patterns.Based on its geological model, the depth of the sediment is relatively shallow between 1500 to 2000 meters. While the integration between seismic, gravity and geomagnetic data shows the discovery of new basins that have never been described before.Finally, the integration of seismic and gravity data succeed discovers a new basin which has never been delineated before. In addition, it shows the continuity of the regional geological structure spanning from the studied area to the West Natuna Basin which is well known to be rich in hydrocarbon potential.

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Chapter 7 Exploration implications

Geological Society London Memoirs ◽

10.1144/m53.7 ◽

2020 ◽

Vol 53 (1) ◽

pp. 187-196 ◽

Cited By ~ 3

Author(s):

A. O. Wilson

Keyword(s):

New Mexico ◽

Cross Sections ◽

The Black Sea ◽

Hydrocarbon System ◽

Future Production ◽

The Usa ◽

Intrashelf Basin ◽

The Uk ◽

Basin Area ◽

Reservoir Facies

AbstractExploration of the Jurassic hydrocarbon system in the Arabian Intrashelf Basin area is in a mature state. Given the scale of the present day anticlinal structures and the adjacent synclines, all of the supergiant conventional fields trapped in huge anticlines have already been discovered. The theme throughout this Memoir has been to present the evolution of the self-contained Callovian–Tithonian Arabian Intrashelf Basin hydrocarbon system. Its size, c. 1200 × 450 km, is greater than that of the UK, larger than the Black Sea and almost as large as Turkey or the area of Texas and New Mexico in the USA. It is geologically much simpler than these regions, both in the exceptionally remarkable continuity of facies within the sequences that developed and filled the intrashelf basin and its relative tectonic simplicity, including up to the present day. The cross-sections, facies maps, depositional profiles and other data and interpretations presented in this Memoir have documented this remarkable continuity. The source rock interval is well-defined everywhere it occurs and is mature; enough oil has been generated and migrated so that every sealed trap with reservoir facies will have oil. Around and within the basin, shallow water ramp facies in each sequence are in the reservoir facies and the early-formed porosity has been preserved. The carbonate seals and, even more so, the evaporite seals are remarkably laterally continuous. Therefore the big issue in future exploration is finding a sealed trap with potential reserves large enough to be worth drilling when compared to known reserves and estimates of future production. This chapter discusses some possibilities for stratigraphic traps and unconventional plays. Potential plays have been and/or can be identified, but finding them in the present day structural setting is likely to be very difficult.

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Three‐dimensional gravity or magnetic constrained depth inversion with lateral and vertical variation of contrast

Geophysics ◽

10.1190/1.1442840 ◽

1990 ◽

Vol 55 (3) ◽

pp. 327-335 ◽

Cited By ~ 13

Author(s):

D. Chenot ◽

N. Debeglia

Keyword(s):

Gravity Data ◽

Three Dimensional ◽

Sediment Compaction ◽

Inhomogeneous Density ◽

Dimensional Gravity ◽

Well Data ◽

Starting Model ◽

Basin Area ◽

Local Depth

Depth‐mapping inversion of gravity or magnetic fields generally assumes that anomalies originate from a main density or magnetization contrast interface. This particular inversion takes into account inhomogeneous density or magnetization distributions reflecting sediment compaction and basement heterogeneities: above the interface, the density can be approximated by an exponential function, and below it, an intrabasement contrast map can be used. The inversion also integrates local depth constraints from wells or seismic data, as well as general constraints set on the geometry and the contrast of the interface. After field transformations, spectral analysis and constraints help to define a starting model characterized mainly by the interface mean depth and the mean parameter contrast between the two media. The depth adjustment is completed iteratively under constraints using a space‐domain formulation derived from the Bouguer‐slab approximation. The interface model effect is computed in the wavenumber domain. A model data example shows the accuracy of the inversion and illustrates the role of the constraints. In a field example of a basin area where constraints can be derived from numerous well data, successive inversions of gravity data result in an isodepth map of the basement. The compatibility of the map with local depth constraints from wells is obtained by taking into account density heterogeneities related to known lithologic variations in the basement.

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