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Abstract. Lake Victoria, which is bordered by Uganda, Tanzania, Kenya, and has a catchment that extends to Rwanda and Burundi, is home to the largest human population surrounding any lake in the world and provides critical resources across eastern Africa. Lake Victoria is also the world's largest tropical lake by surface area, but it is relatively shallow and without a major inlet, making it very sensitive to changes in climate, and especially hydroclimate. Furthermore, its size creates abundant habitats for aquatic fauna, including the iconic hyper-diverse cichlids, and serves as a major geographic barrier to terrestrial fauna across equatorial Africa. Given Lake Victoria's importance to the eastern African region, its sensitivity to climate, and its influences on terrestrial and aquatic faunal evolution and dispersal, it is vital to understand the connection between the lake and regional climate and how the lake size, shape, and depth have changed through its depositional history. This information can only be ascertained by collecting a complete archive of Lake Victoria's sedimentary record. To evaluate the Lake Victoria basin as a potential drilling target, ∼ 50 scientists from 10 countries met in Dar es Salaam, Tanzania, in July 2022 for the International Continental Scientific Drilling Program (ICDP)-sponsored Lake Victoria Drilling Project (LVDP) workshop. Discussions of the main scientific objectives for a future drilling project included (1) recovering the Pleistocene and Holocene sedimentary records of Lake Victoria that document the dynamic nature of the lake, including multiple lacustrine and paleosol sequences; (2) establishing the chronology of recovered sediments, including using extensive tephra fingerprinting and other techniques from deposits in the region; (3) reconstructing past climate, environment, lacustrine conditions, and aquatic fauna, using an integrated multi-proxy approach, combined with climate and hydrologic modeling; and (4) connecting new records with existing sedimentary snapshots and fossils exposed in deposits around the lake, tying archaeological, paleontological, sedimentological, tectonic, and volcanic findings to new drilling results. The LVDP provides an innovative way to address critical geological, paleontological, climatological, and evolutionary biological questions about Quaternary to modern landscapes and ecosystems in eastern Africa. Importantly, this project affords an excellent opportunity to help develop conservation and management strategies for regional responses to current and future changes in climate, land use, fisheries, and resiliency of at-risk communities in equatorial Africa.
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ICDP workshop on the Lake Tanganyika Scientific Drilling Project: a late Miocene–present record of climate, rifting, and ecosystem evolution from the world's oldest tropical lake
Abstract. The Neogene and Quaternary are characterized by enormous changes in globalclimate and environments, including global cooling and the establishment ofnorthern high-latitude glaciers. These changes reshaped global ecosystems,including the emergence of tropical dry forests and savannahs that are foundin Africa today, which in turn may have influenced the evolution of humansand their ancestors. However, despite decades of research we lack long,continuous, well-resolved records of tropical climate, ecosystem changes,and surface processes necessary to understand their interactions andinfluences on evolutionary processes. Lake Tanganyika, Africa, contains themost continuous, long continental climate record from the mid-Miocene(∼10 Ma) to the present anywhere in the tropics and has longbeen recognized as a top-priority site for scientific drilling. The lake issurrounded by the Miombo woodlands, part of the largest dry tropical biomeon Earth. Lake Tanganyika also harbors incredibly diverse endemic biotaand an entirely unexplored deep microbial biosphere, and it provides textbookexamples of rift segmentation, fault behavior, and associated surfaceprocesses. To evaluate the interdisciplinary scientific opportunities thatan ICDP drilling program at Lake Tanganyika could offer, more than 70scientists representing 12 countries and a variety of scientificdisciplines met in Dar es Salaam, Tanzania, in June 2019. The teamdeveloped key research objectives in basin evolution, source-to-sinksedimentology, organismal evolution, geomicrobiology, paleoclimatology,paleolimnology, terrestrial paleoecology, paleoanthropology, andgeochronology to be addressed through scientific drilling on LakeTanganyika. They also identified drilling targets and strategies, logisticalchallenges, and education and capacity building programs to be carried outthrough the project. Participants concluded that a drilling program at LakeTanganyika would produce the first continuous Miocene–present record fromthe tropics, transforming our understanding of global environmental change,the environmental context of human origins in Africa, and providing adetailed window into the dynamics, tempo and mode of biologicaldiversification and adaptive radiations.
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- PAR ID:
- 10226047
- Date Published:
- Journal Name:
- Scientific Drilling
- Volume:
- 27
- ISSN:
- 1816-3459
- Page Range / eLocation ID:
- 53 to 60
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.5194/sd-27-53-2020
