Marquardt inverse modeling of the residual gravity anomalies due to simple geometric structures: A case study of chromite deposit

  • Ata ESHAGHZADEH Institute of Geophysics, University of Tehran, Iran
  • Alireza DEHGHANPOUR Islamic Azad University, Science and Research Branch, Tehran, Iran
  • Sanaz SEYEDI SAHEBARI Roshdiyeh Higher Education Institute, Tabriz, Iran
Keywords: chromite deposit, gravity anomaly, Marquardt’s algorithm, simple geometric shapes

Abstract

In this paper, an inversion method based on the Marquardt’s algorithm is presented to invert the gravity anomaly of the simple geometric shapes. The inversion outputs are the depth and radius parameters. We investigate three different shapes, i.e. the sphere, infinite horizontal cylinder and semi-infinite vertical cylinder for modeling. The proposed method is used for analyzing the gravity anomalies from assumed models with different initial parameters in all cases as the synthetic data are without noise and also corrupted with noise to evaluate the ability of the procedure. We also employ this approach for modeling the gravity anomaly due to a chromite deposit mass, situated east of Sabzevar, Iran. The lowest error between the theoretical anomaly and computed anomaly from inverted parameters, determine the shape of the causative mass. The inversion using different initial models for the theoretical gravity and also for real gravity data yields approximately consistent solutions. According to the interpreted parameters, the best shape that can imagine for the gravity anomaly source is the vertical cylinder with a depth to top of 7.4 m and a radius of 11.7 m.

Author Biographies

Ata ESHAGHZADEH, Institute of Geophysics, University of Tehran, Iran

Graduate student of geophysics

Alireza DEHGHANPOUR, Islamic Azad University, Science and Research Branch, Tehran, Iran

Graduate student of geophysics

Sanaz SEYEDI SAHEBARI, Roshdiyeh Higher Education Institute, Tabriz, Iran

Instructor

Published
2019-06-30
How to Cite
ESHAGHZADEH, A., DEHGHANPOUR, A., & SEYEDI SAHEBARI, S. (2019). Marquardt inverse modeling of the residual gravity anomalies due to simple geometric structures: A case study of chromite deposit. Contributions to Geophysics and Geodesy, 49(2), 153-180. https://doi.org/10.2478/congeo-2019-0008
Section
original research papers