TECTONIC CONFIGURATION OF THE MALAWI RIFT REVEALED FROM CRUSTAL THICKNESS MODEL

In this study, a crustal thickness model of the Malawi rift is created from the inversion of the EIGEN-6C4 global gravity model. The regularized inversion based on the Gauss- Newton formulation of Bott's equation is employed to resolve the Moho topography. The inversion process uses tesseroids to account for the earth's curvature. Moho depth modeling for such a massive landmass cannot ignore the earth's curvature. The Bouguer effect, terrain effect, and gravity effect due to sediments are also corrected and calculated in a spherical approximation. The resulting crustal thickness model was validated seismology.

In this study, a crustal thickness model of the Malawi rift is created from the inversion of the EIGEN-6C4 global gravity model. The regularized inversion based on the Gauss- Newton formulation of Bott's equation is employed to resolve the Moho topography. Moho depth modeling for such a massive landmass cannot ignore the earth's curvature. The Bouguer effect, terrain effect, and gravity effect due to sediments are also corrected and calculated in a spherical approximation.

Malawi is part of the sub-Sahara of Africa and is a landlocked country located in the southeastern part of the continent. Composed of 45,747 square miles Malawi is bordered in the north and east by Tanzania, to the east, south, and southwest by Mozambique, and the west by the nation of Zambia. Much of the land surface of Malawi is a large plateau that is between 914.4 to 1219.2 meters above sea level. Elevations rise over about 2500 meters in the Nyika Plateau, Zomba mountain approximately 2087 meters and 3002 meters Mulanje mountain. The Shire highlands in the south are the lowest area in the country with elevations extending from 609.6 to 914.4 meters. The Malawi rift which is located at the southern end of the western area of the East African Rift between 90 and 140S is the prominent example of immature rifting hence making the rift system dynamic and two-thirds of it is covered by Lake Malawi (Grijalva, et al., 2018).

District: Blantyre

Coordinates: -15.6817, 34.92535