Ilk_inv: a Matlab based algorithm for rapid computation of pseudo-3D density contrast distribution by using Bouguer gravity data

Year 2021, Volume: 166 Issue: 166, 19 - 31, 15.12.2021

İlkin Özsöz

https://doi.org/10.19111/bulletinofmre.959011

Abstract

The new generation Matlab-based algorithm provides a rapid estimation of density contrast distribution. The 3D assumption, which is based on the 1D equation, is used. Therefore, the output is called pseudo-3D instead of 3D. The algorithm uses singular value decomposition and the median filter to produce pseudo-3D results. The success of the method is tested by theoretical and field studies. For synthetic studies,  ingle-source models produce reasonable outputs, compared to the true density contrast value. However, the multiple source model shows slight deviations which are ±0.3 g/cm³, with respect to the true density contrast value. The acceptable results are observed for the Bouguer anomaly of the eastern Mediterranean region. The resolution matrix indicates that the inversion process is biased due to the generalised  inverse. The algorithm provides a quite different qualitative interpretation perspective to the interpreter.

Keywords

Singular Value Decomposition, Pseudo- 3D Density Map, Gravity Modelling.

Thanks

I would like to offer my special thanks to Dr. Chris GREEN for his insightful contributions to the theory of the algorithm. Moreover, I am grateful to anonymous reviewers for their comments.

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