Synthesizing emerging results and identifying future research in an early-stage, magma-poor rift: A workshop in the southern East Africa Rift System

Northern Arizona University, Flagstaff AZ

Investigators

Abstract

The East Africa Rift System (EARS) is one of the best examples in the world of a continent that is actively in the process of stretching and breaking apart; in the past, these geological processes have culminated in the breakup of continents and formation of ocean basins like the Atlantic Ocean. Although continental stretching and breakup has occurred repeatedly over Earth’s history, the early stages in this process remain poorly understood. In addition to being an important scientific topic, continental stretching is also essential to understand for assessing geohazards; rift zones like the East Africa Rift System are seismically and volcanically active. Over the past 10 years, a number of new scientific studies focused on the southern part of the East Africa Rift System have emerged that are providing new and surprising insights into the onset of continental breakup. This award will support a 4-day workshop in the summer of 2021 in Malawi, which is located within the rift valley, to bring together ~50 US and African scientists to share and synthesize the results of these recent studies to achieve a more comprehensive understanding of continental stretching and associated hazards in the southern part of the East Africa Rift system. This workshop will also provide opportunities to strengthen existing relationships and form new collaborations between US and African scientists, training for early career scientists, and public outreach on the rift and its hazards. The EARS exhibits along-strike changes in magmatism, deformation and cumulative stretching, offering the opportunity to examine active rifting processes at different stages of development and study controls on rifting. These attributes made the EARS an excellent locality to address major questions about rifting posed in the NSF GeoPRISMS science plan. The southern section of the EARS constitutes an endmember of this system in two important respects: 1) there is limited volcanism at the surface, providing the opportunity to more fully test models that require magmatism to weaken and thin the lithosphere, and 2) relatively little cumulative stretching has occurred, making it possible to observe controls on rift initiation. In the last ~5 years, a number of US and international studies have yielded interesting and surprising results on the southern EAR. However, because many EARS-related efforts were funded late in the GeoPRISMS program due to the phased funding model and/or leveraged efforts funded by other programs, there has not been an opportunity for the interdisciplinary community to meet and discuss these results in the context of the GeoPRISMS efforts. The 4-day workshop supported by this award will enable US and African scientists to meet in person and share results; in-person meetings are essential to foster communication and develop and maintain strong international collaborations. The workshop will take place in the summer of 2021 in Malawi, which is located within the rift valley, central to the focus area of the workshop. Holding the meeting here will enable participation by more African scientists, facilitate more networking between US and Africa scientists, and allow for education and outreach efforts associated with the workshop. We will carefully select attendees by application in order to ensure that participants represent a cross-section of expertise, career stage and experience working in Africa This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.