42-1 Reflections on Deep Lake Drilling – 20 years of Science from Lake Malawi (Nyasa) Drill Cores

Session: Integrating 20 Years of Scientific Drilling in the East African-Syrian Rift: A Session In Honor of Andrew Cohen, Part II

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The concept of deep scientific drilling in the East African Great Lakes as a realizable scientific quest first materialized in 1980, at a workshop funded by the National Science Foundation and organized by Dan Livingstone of Duke University. Those in attendance (and greatly inspired) included Andrew Cohen, then a graduate student at UC Davis. Subsequently, in the 1980’s, the work of Project PROBE, also based at Duke University and led by Bruce Rosendahl, produced spectacular subsurface images of the East African Great Lakes, and provided new insights into continental rifting. These seismic data confirmed previous speculation about the antiquity of the rift valley and its remarkable lakes and paved the way for deep drilling on Lake Malawi (Nyasa). Prospects for global scientific lake drilling gained considerable traction in the 1990’s following drilling at Lake Biwa and Lake Baikal, the establishment of the International Continental Scientific Drilling program, and many more NSF- and ICDP-funded workshops. Our community infrastructure continues to evolve and is now supported by the Continental Scientific Drilling facility based at the University of Minnesota.

The planning and advance engineering work for scientific drilling on Lake Malawi required the better part of a decade and was only possible due to the confluence of many factors; Andrew Cohen played a pivotal role in advising the project and coordinating the program. The drilling occurred in early 2005 and was at the time the deepest and longest lake drilling effort attempted, and to date is the only global lake drilling project that utilized dynamic positioning to operate in deep water (600 m water depth in this project). The scientific results arising from this longest, most continuous high-resolution paleoclimate record in the continental tropics include seminal observations on orbital-scale hydroclimate, paleotemperature, landscape evolution and regional vegetation shifts; high-frequency climate perturbations teleconnected to global abrupt events; evolutionary dynamics including impacts on endemic fish and phytoplankton evolution; globally-impactful volcanic eruptions (e.g., discovery of the Toba ash); and many others. These drill cores remain a treasured archive, and work on the cores continues, including at present helping decipher long-term seismicity trends, normal fault behaviors and assessing earthquake risks in the Malawi (Nyasa) Rift Valley.

Geological Society of America Abstracts with Program. Vol. 57, No. 6, 2025

doi: 10.1130/abs/2025AM-8766

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