Development of a user's-friendly algorithm for gravimetric data processing Using Visushrink thresholds technique in a standalone tool

Abstract

Gravity is an efficient means of determining the shape and size of the Earth as well as the exploration of natural resources beneath the Earth's surface by examining the sudden variations in the fields (gravity anomalies) caused by the heterogeneous nature of Earth's
materials. To satisfactorily and optimally separate the gravity anomalies into regional (deep sources) and residual (shallow sources) components has constrained the use of gravimetric data for geodetic and geophysical exploration. In this paper, an attempt was made to optimally separate gravity anomalies into regional and residual components for geodetic and geophysical surveying using the Visushrink thresholds technique in the Discrete Wavelet domain. Gravity anomalies over an area in the Gongola Basin of Nigeria were obtained and used. The method was found to yield a good Regional Residual Ratio of 22.3113db and a regional anomalies variance of 6.2545 which is smoother and better than the Regional and Residual Ratio of 19.4197dB and a regional anomalies variance of 6.6488 obtained from theleast square collocation technique. In separating gravity anomalies into regional and residual components, the VisuShrink Thresholding technique of Discrete Wavelet Transformation is recommended.