Tectonic control over active volcanism at a range of scales: Case of the Rungwe Volcanic Province, SW Tanzania; and hazard implications

The volcano-tectonic architecture of the Rungwe Volcanic Province in SW Tanzania, part of the East African Rift System, was studied with integrated remote sensing imagery. A Shuttle Radar Topography Mission Digital Elevation Model was draped with geo-referenced geological and topographical maps and air photos. The entire RVP region was inspected systematically for tectonic lineaments and volcanic vents. Tectonic lineaments show two distinct directions, NW-SE and NNE-SSW, consistent with the idea of a current stress regime of local NE-SW compression. We find that there is tectonic control on the regional location for at least two of the three major volcanoes as well as for local distribution of eruptive vents on each of these three volcanoes. Field data show that major volcano instability events occurred in the Holocene for Ngozi caldera and Rungwe. These instability events are possibly associated with the faults controlling the location of both volcanoes. This study highlights the need for monitoring RVP tectonic and volcanic activity.