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The Neogene and Quaternary are characterized by enormous changes in global climate and environments, including global cooling and the establishment of northern high-latitude glaciers. These changes reshaped global ecosystems, including the emergence of tropical dry forests and savannahs that are found in Africa today, which in turn may have influenced the evolution of humans and 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 and influences on evolutionary processes. Lake Tanganyika, Africa, contains the most continuous, long continental climate record from the mid-Miocene (∼ 10 Ma) to the present anywhere in the tropics and has long been recognized as a top-priority site for scientific drilling. The lake is surrounded by the Miombo woodlands, part of the largest dry tropical biome on Earth. Lake Tanganyika also harbors incredibly diverse endemic biota and an entirely unexplored deep microbial biosphere, and it provides textbook examples of rift segmentation, fault behavior, and associated surface processes. To evaluate the interdisciplinary scientific opportunities that an ICDP drilling program at Lake Tanganyika could offer, more than 70 scientists representing 12 countries and a variety of scientific disciplines met in Dar es Salaam, Tanzania, in June 2019. The team developed key research objectives in basin evolution, source-to-sink sedimentology, organismal evolution, geomicrobiology, paleoclimatology, paleolimnology, terrestrial paleoecology, paleoanthropology, and geochronology to be addressed through scientific drilling on Lake Tanganyika. They also identified drilling targets and strategies, logistical challenges, and education and capacity building programs to be carried out through the project. Participants concluded that a drilling program at Lake Tanganyika would produce the first continuous Mioce, SCOPUS: ar.j, info:eu-repo/semantics/published

Lake Tanganyika is the most widely cited modern analog for interpreting ancient rift-lake deposits. The lake consists of a series of half-grabens linked by a series of structural horsts. This asymmetric geometry allows classification of the basin margin into four distinct types of lake margins: escarpment (footwall), accommodation zone (structural horsts), axial, and hinged (hangingwall). Sedimentologic study of six study sites that represent all four margin types indicates that margin geomorphology, such as (e.g. depositional slope, and drainage size) and littoral sedimentology (e.g. occurrence of shore-parallel facies belts, and presence of certain environments such as winnowed surfaces, fan-deltas) differ significantly among the structural margin types. Compositional differences among the sites also reflect the structurally controlled variability in sedimentary processes. Total Organic Carbon (TOC) and Rock-Eval pyrolysis data show that relatively rich, hydrogen-rich organic matter typically accumulates along the accommodation-zone and escarpment margins, whereas typically lean, oxidized organic accumulates along axial and hinged margins. Sand composition among the margin types of Lake Tanganyika clusters tightly using the Gazzi-Dickinson point-counting methodology, confirming that provenance variability is generally minor. However, significant compositional differences among the tectonic margins appear when these data are cast using the traditional point-counting methodology. These compositional differences are primarily controlled by transport and depositional processes that vary among the sites. The Apache Canyon Formation, a mixed carbonate-clastic lacustrine sequence deposited within the extensional Bisbee basin of southeastern Arizona, provides a test of predictive capacities of the basin-fill model developed from the Lake Tanganyika data. Three measured sections, located along a transect perpendicular to the basin-bounding fault, are generally consistent w