Lithologic characterization using magnetic and gravity gradient data over an iron ore formation

*Cericia Martinez†,Yaoguo Li†, Richard Krahenbuhl†, Marco Braga‡
†Center for Gravity, Electrical, and Magnetic Studies, Department of Geophysics, Colorado School of Mines
‡Vale, Brazil

ABSTRACT

Magnetic and gravity gradient data over part of the Gandarela Syncline iron formation in the Quadrilátero Ferrífero have been utilized to obtain a 3D susceptibility and density contrast model using inversion. It is possible to use these detailed 3D physical property distributions of subsurface features for lithologic interpretation purposes. We group the two physical property distributions into geologically representative units. A distribution of these lithologic units can then be organized in a model similar to the susceptibility and density distributions in order to help characterize subsurface structure.