Combination of horizontal gradient ratio and Euler methods for the interpretation of potential field data

Abstract

The horizontal gradient ratio has been widely used to enhance the linear features of potential field data. I explore a combination of the horizontal gradient ratio and Euler method to interpret gridded potential field data, called HGR-EUL method. A linear equation derived for the Euler equation and expressing the fields as horizontal gradient ratio can be used to estimate the horizontal location and the depth of the source without any priori information about the nature (structural index) of the source. After obtaining the source location parameters, the nature of the source can be determined. The HGR-EUL method is tested on synthetic magnetic anomalies, and the inversion results show that the method can accurately provide the location parameters for noise-free data, and also obtain reasonable results for noise-corrupted data by applying a low pass filter to smooth the data. I also applied the HGR-EUL method to real magnetic data, and the results are compared with results from the standard Euler deconvolution method. The results obtained by the HGR-EUL method show less unjustified variability and are more useful for geologists.

A Note on the Use of the Second Vertical Derivative (SVD) of Gravity Data with Reference to Indonesian Cases

“…Horizontal and vertical gradients are expected to enhance anomalous source boundaries from anomaly maps [1,2]. On the other hand, decaying characteristics of the anomaly may be used to infer the lateral position and depth of simple or elementary anomalous sources, as in Euler deconvolution or its variants [3,4].…”

Ratio‐Euler deconvolution and its applications

“…For example, Keating and Pilkington (2004) apply the Euler equation to analytic signal of the potential field to estimate source location and SI simultaneously. Salem et al (2008) develop a linear equation without the parameter SI by applying tilt angle, which is known as Tilt-Euler method and followed by many researches (Ma, 2013(Ma, , 2014Alamdar et al, 2014;Guo et al, 2014Guo et al, , 2020Wang et al, 2019). In our previous studies, we also suggest an improved Euler method to avoid the parameter SI (Huang et al, 2019) based on high-order derivatives.…”

“…Since it was first developed by Thompson (1982) and applied to magnetic data interpretation, Euler deconvolution has been extensively studied (Reid et al ., 1990; Barbosa et al ., 1999; Zhang et al ., 2000; Mushayandebvu et al ., 2001; Nabighian & Hansen, 2001; Hsu, 2002; FitzGerald et al ., 2004; Gerovska et al ., 2005; Salem et al ., 2008; Fedi et al ., 2009; Ma, 2013; Alamdar et al ., 2014; Cooper, 2014; Zhou et al ., 2016; Melo & Barbosa, 2018, 2020; Huang et al ., 2019; Amaral Mota et al ., 2020). In the standard Euler deconvolution (Thompson, 1982; Reid et al ., 1990), a source parameter, known as the SI, needs to be determined before the calculation.…”

“…However, it is a challenge to determine an optimal SI when we know less about the subsurface sources’ shape, especially when the potential field from multiple different sources with different SI interferes with each other (Hsu, 2002). Consequently, lots of methods have been developed without specifying the SI (Roy et al ., 2000; Hsu, 2002; Keating & Pilkington, 2004; Gerovska et al ., 2005; Salem et al ., 2008; Beiki, 2010; Davis et al ., 2010; Ma, 2013, 2014; Alamdar et al ., 2014; Zhou et al ., 2016; Liu et al ., 2019). For example, Keating and Pilkington (2004) apply the Euler equation to analytic signal of the potential field to estimate source location and SI simultaneously.…”

Balanced gradient methods for the interpretation of gravity tensor gradient data

“…We also apply a four steps clustering method to get better image of the horizontal location and depth of the causative source (Reid et al, 1990;Ma, 2013;Ma et al, 2013).…”