Сравнение глобальных моделей гравитационного поля на территории Магаданской области

Abstract

The global databases of gravity anomalies, currently available to researchers, provide a new informative tool for constructing density models of the deep structure of the earth's crust for individual regions. Currently, there are six models of gravitational anomalies, presented as a series of spherical harmonics up to 2190 degrees, which corresponds to about 10 km on the earth's surface. Different methods of processing terrestrial, marine, aerial, and satellite gravimetric data, available to their authors, determine the differences between these models, both on a global scale and within specific regions. We have performed a comparison of the EGM2008, GECO, EIGEN-6C4, and WGM2012 models with the Gravimag database on the Magadan Oblast territory. The comparison showed that free air anomalies for the EGM2008, GECO, EIGEN-6C4, and WGM2012 models in the selected area almost coincide. Bouguer anomalies of the WGM2012 model can be used in regional density modeling for adjacent regions where there are no conventional ground gravity data; however, within Magadan Oblast the Gravimag database has the best data quality.