PETROLEUM RESOURCE POTENTIAL ASSESSMENT USING GRAVITY DATA IN LOWER SHIRE BASIN

The Lower Shire Basin of Malawi is a region with a significant potential for petroleum resources, however, the exact extent and location of these resources are not well understood. This study aims to assess the petroleum potential of the Lower Shire Basin using gravity data. The Bouguer anomaly map obtained from Geological Survey Department of Malawi was interpreted to identify the geological structure of the basin and the depth to the basement rocks. The results indicate that the Lower Shire Basin is composed of several faulted blocks. The depth to the basement rocks ranges from 0.5 km to 3.5 km. The gravity data also revealed areas of low density, which may be indicative of hydrocarbon accumulations. These results suggest that the Lower Shire Basin has a significant potential for petroleum resources and further exploration is warranted.

The Lower Shire Basin of Malawi is a region with a significant potential for petroleum resources, however, the exact extent and location of these resources are not well understood. This study aims to assess the petroleum potential of the Lower Shire Basin using gravity data. The Bouguer anomaly map obtained from Geological Survey Department of Malawi was interpreted to identify the geological structure of the basin and the depth to the basement rocks. These results suggest that the Lower Shire Basin has a significant potential for petroleum resources and further exploration is warranted.

The most recent structural understanding of the Lower Shire Basin is drawn from the analysis of Lengwe, Mwabvi and Ngabu domains (Castaing, 1991; Chisenga et al., 2019).
The Lower Shire Basin can be described as an area of repeated stress regimes beginning from the Karoo rifting period when NW-SE extension produced NE-SW grabens (Castaing, 1990, 1991). This regime was followed by sinistral slip systems with a slight normal component which enabled the NW-SE faults such as the Mwanza Fault to play a significant role in the evolution of the Karoo basins of the Shire Valley (Castaing, 1991).
The Karoo sedimentation and magmatism of the Lower Shire Basin was controlled by NW-SE extensional tectonic regime in which the minimum stress of the δ3 was dominant from the Permian to the Lower Jurassic. The basaltic magmatic phase was initiated as the late phase of the basin development and were followed by Stomberg dolerite dyke injection that are a manifestation of the last phase of basin rifting during Gondwana evolution.

District: Chikwawa

Coordinates: -16.2153, 34.6804