Application of Forward and Inverse Modelling to High-Resolution Gravity Data for Mineral Exploration

Document Type : Research Article

Authors

1 Senior Lecturer, Department of Physics, College of Physical Sciences, Federal University of Agriculture, Abeokuta, Nigeria

2 M.Sc. Student, Department of Physics, College of Physical Sciences, Federal University of Agriculture, Abeokuta, Nigeria

3 Professor, Department of Physics, College of Physical Sciences, Federal University of Agriculture, Abeokuta, Nigeria

Abstract

Gravity survey is a geophysical tool used to investigate the subsurface by measuring the differences in Earth’s gravitational field. The high-resolution gravity data within latitude 70.00׀ - 70.30 ׀N, and longitude 30.00 ׀- 30.30 ׀E was acquired through Bureau Gravimetrique Internationale (EGM2008). The research work employed the methods of the filtering techniques as well as forward and inverse modelling for data analysis and interpretations. The qualitative results of the gravity anomaly of the field through the regional-residual separation technique and the high pass filters show the local and geologic features of the study area. The low, fairly high and high-density areas are characterized by alluvial, meta-sediments/sedimentary and igneous deposits respectively. The derivative maps aided the locations, boundaries and edges of anomalous bodies, including the transition zones and sedimentary intrusions of the study area. Forward and inverse modeling techniques were applied to profiles (P1-P4) in a quantitative approach, to describe the geometry, density contrast, depth, position, strike, dip and plunge. The depth range of 1268 m to 3111 m was calculated, while the density contrasts of gravity bodies suggest the presence of mineral rocks such as limestone, quartz, gneiss, sandstone, schist, granite, quartzite and gypsum.

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References

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Journal of the Earth and Space Physics
Volume 46, Issue 4
February 2021
Pages 117-129

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