US-Malawi Planning Visit: Developing a Multidisciplinary, Multinational Study of Continental Rifting, Seismicity and Volcanism Around Northern Lake Malawi

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Intellectual Merit: The ~2500-km-long East Africa Rift system is one of the best examples of active rifting of a continent in the world. Volcanism and seismicity associated with rifting pose a substantial risk to people who live in or near the rift valley. We are developing a multidisciplinary, multinational project to investigate the region around northern Lake Malawi in the southern part of the East Africa Rift system. We recently submitted a pre-proposal for this project to Continental Dynamics (1 April 2009), and plan to submit a full proposal for the 15 November 2009 deadline. Our project would involve scientists and students from the U.S., Malawi and Tanzania, and we plan to further contribute to scientific infrastructure and education in this region through AfricaArray. Our proposed project would involve imaging of the sediments, crust and mantle lithosphere around northern Lake Malawi, monitoring of surface deformation and seismicity over a 2-4 year time period, and geochemical analysis of volcanic rocks from a magmatic province at the north end of the lake. This powerful combination of temporal and spatial constraints will enable us to obtain unique insights into magmatic and tectonic processes throughout the lithosphere during early rifting. These datasets would also be applied to geohazard characterization and mitigation. We propose a planning trip for four US scientists to visit Malawi in order to strengthen relationships with foreign scientists and to solve key logistical challenges. US scientists will meet with Dr. Leonard Kalindekafe, Director of the Geological Survey of Malawi, and Mrs. Lostina Chapola, Head of the Geography Department at the Catholic University of Malawi, as well as other scientists and officials in relevant government ministries. Together, they will make specific plans for the full proposal, which will be submitted in November. Our ambitious project also poses several logistical challenges, particularly the identification of an appropriate vessel to deploy geophysical instrumentation and acquire data within the lake. A significant portion of the trip will be spent assessing academic and industry vessels. These particular PI?s from the Continental Dynamics proposal will be most closely involved in different aspects of the ?marine? portion of the experiment, and are thus needed to assess port facilities and ships. Finally, we propose to visit the field region to assess different strategies for deploying onshore instruments in the rugged terrain around the lake, inspect port facilities at Nkhata Bay and Chilumba, and acquire preliminary data for planning purposes. We plan to re-occupy two GPS monuments in our proposed study area (which were installed and used for data acquisition in 1997) for two to three days.Broader Impacts: Magmatism and seismicity associated with extension in this part of the Western Rift pose a serious hazard to surrounding communities in Malawi and Tanzania, particularly those residing near the Rungwe volcanic province. Our proposed Continental Dynamics program will provide unprecedented details on seismicity and present-day deformation in this region, which can inform hazard assessment and mitigation. Additionally, our study complements other active research and outreach efforts in this region, such as the Lake Malawi Drilling Project; it would provide a broader tectonic context for results on recent climate changes and the evolution of early humans. Our project will also contribute to scientific education and research in this region by augmenting AfricaArray (www.africaarray.org). The proposed program includes support for graduate students from Malawi and Tanzania, who will participate in acquiring data, evaluating geo-hazards, and analyzing the resulting datasets. Data from our temporary deployment will complement permanent and temporary AfricaArray stations in the south EARS, enhancing the value of both datasets. The team of US scientists contains a mixture of senior and junior scientists with a spread of expertise and varying levels of experience working in Africa. A planning trip would make it possible for them to gain local knowledge and strengthen collaborations in Malawi in order to develop a viable plan for a major investigation in this region. The longer-term impact of this trip is that it provides the opportunity for several scientists, including two early-career scientists, who have never worked in Africa to develop the contacts and familiarity necessary to plan and execute future scientific and educational programs here.