Abstract
An automatic inversion using ridge regression algorithm is developed in the space domain to analyze the gravity anomalies of sedimentary basins, among which the density contrast decreases with depth following a prescribed exponential function. A stack of vertical prisms having equal widths, whose depths become the unknown parameters to be estimated, describes the geometry of a sedimentary basin above the basement complex. Because no closed form analytical equation can be derivable in the space domain using the exponential density-depth function, a combination of analytical and numerical approaches is used to realize forward gravity modeling. The depth estimates of sediment-basement interface are initiated and subsequently improved iteratively by minimizing the objective function between the observed and modeled gravity anomalies within the specified convergence criteria. Two gravity anomaly profiles, one synthetic and a real, are interpreted using the proposed technique to demonstrate its applicability.
Highlights
Gravity method plays an important role in the studies related to sedimentary basin modeling because detectable gravity anomalies can be observable on the surface of the Earth due to the presence of significant density contrast between sediment infill and the underlying basement
We develop a space domain based inversion technique to analyze the gravity anomalies of sedimentary basins, among which the density contrast varies exponentially with depth
We develop a space domain based inversion technique using the ridge regression algorithm to analyze the gravity anomalies of sedimentary basins among which the density contrast obeys exponential decrease with depth
Summary
Gravity method plays an important role in the studies related to sedimentary basin modeling because detectable gravity anomalies can be observable on the surface of the Earth due to the presence of significant density contrast between sediment infill and the underlying basement. Due to deficit in density of sedimentary rocks with the underlying basement complex, negative gravity anomalies are usually observed over sedimentary basins It is well-known that the interpretation of gravity anomalies for subsurface density structure(s) is a non-unique problem, because the surface gravity anomalies can be explained by a variety of mass distributions at different depths (Blakely 1995). Many 2D indirect methods (forward modeling) are available to compute the gravity anomalies of geological sources with uniform density (e.g., Won and Bevis 1987, Singh 2002) These forward modeling techniques find limited application in analyzing gravity anomalies of sedimentary basins because the parameters describing the structure are not known in advance. The applicability of the method is exemplified with both synthetic and real field examples
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
