Microearthquake Survey at the Buranga Geothermal Prospect, Western Uganda

Abstract

The BGR supports the Government of Uganda in the geoscientific investigations at the Buranga geothermal prospect since 2004. The objective of the project is to raise the knowledge about Buranga to a level (pre-feasibility status) that can be the base for planning of exploration wells. Geochemical findings, which have been achieved in the framework of the joint project, proofed the existence of a magmatic body that most likely serves as the heat source of the hot springs. Hence the .task of active ground geophysics was detecting and delineating this magmatic intrusion. The known high seismicity (about 300 local earthquakes per month) suggested that Buranga provides excellent requirements to apply seismology.

From May 2005 to August 2006 up to 15 seismological stations were deployed to record local earthquakes in the Buranga region. The tomography of the seismic data is expected to yield two results:
- Delineation of the underground magmatic intrusion and
- via an exact localization of the hypocenters delineation of the active faults/fault systems.

The first results, which will be reinforced and better elaborated when aJI the data will be included, are presented in this paper. Low velocity anomalies, which most likely represent the magmatic intrusion body, arc shown in horizontal and vertical sections and arc