An improved space domain algorithm for determining the 3-D structure of the magnetic basement

Abstract

The paper presents an improved algorithm based on Bhaskara Rao and Ramesh Babu’s algorithm to invert magnetic anomalies of three-dimensional basement structures. The magnetic basement is approximated by an ensemble of juxtaposed vertical prisms whose bottom surface coincides with Curie surface with the known depth. The computer program operating with the proposed algorithm is built in Matlab environment. Test applications show that the proposed method can perform computations with fast and stable convergence rate where the results also coincide well with the actual model structure. The effectiveness of the method is demonstrated by inverting magnetic anomalies of the southeast part of Vietnam continental shelf. The calculated magnetic basement relief of the study area provides useful additional information for studies in the aim of dealing with the geological structure of the area.References Beiki M., 2010. 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The utility of the enhancement techniques for mapping subsurface structures from gravity data

“…Geophysical methods have been used for many years in the determination of nature and processes of the Earth [1][2][3][4][5][6][7], and gravity method is one of the oldest methods used to solve this problem [8,9]. Despite the development of an increasing number of additional exploration techniques, some of which can determine geological structures with higher resolution, the gravity method has continued to be an important and sometimes crucial constraint in a wide variety of terrestrial investigations [8][9][10].…”

Contribution of advanced edge-detection methods of potential field data in the tectono-structural study of the southwestern part of Cameroon

“…Gravity and magnetic data can provide vital information on the subsurface structures (Dung and Minh, 2017;Hang et al, 2019;Eldosouky et al, 2021a;Eldosouky et al, 2021b;Oksum 2021). The determination of geological boundaries from the interpretation of gravity data has been the subject of several studies, and many different techniques have been introduced (Melouah et al, 2021;Eldosouky et al, 2022a;Pham et al, 2022a;Eldosouky et al, 2022b;Pham et al, 2022b;Eldosouky et al, 2022c;Ghomsi et al, 2022c;Eldosouky et al, 2022d;Ghomsi et al, 2022d), such as, for example, the peak detection methods (Blakely and Simpson, 1986;Hang et al, 2017;Pham et al, 2018;Pham et al, 2021), vertical derivatives, the filters of horizontal gradient (Cordell, 1979;Cordell and Grauch, 1985), the analytical signal (Nabighian, 1972;Nabighian, 1984;Roest et al, 1992), tilt angle (Miller and Singh, 1994), the horizontal gradient amplitude of tilt angle (Verduzco et al, 2004), enhanced horizontal gradient amplitude (Pham et al, 2020a), improved logistic function (Pham et al, 2020b), and balanced horizontal gradient amplitude filters (Prasad et al, 2022a;Prasad et al, 2022b).…”