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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

The shallow water carbonate basin of the Zanzibar channel, Tanzania, has been investigated. This study discusses and describes the sea bottom topographic features, sediment composition, major characteristics of sediment distribution, provenance of sediments, and the depositional settings of the sediments . Zanzibar Channel consists of a Acentral deep@, a feature which is about 30-40 m in depth and approximately in the middle of the channel. The central deep is flanked to the east by an irregular topography, and to the west by a smooth topography. The morphological differences between the two sides of the channel are interpreted as partly caused by the differences in the tectonic development and partly due to differences in the deposition of land derived sediments on either side of the channel. The observed physiographic and tectonic difference between the western and eastern side of the channel have to a large extent controlled the major trends found in the sediment composition and distributions. The surface sediment composition is dominantly of biogenic origin except adjacent to the mainland coastline where the flux of siliciclastic (terrigenous) material from Rivers Ruvu and Wami occur along an approximately 5 km coastal band, and a thin lobe which projects from River Ruvu to the middle of the channel. The minor contribution of siliciclastic sediments originating from Zanzibar Island are generally limited to the intertidal areas west of the island. The lack of significant siliciclastic flux from Zanzibar Island and the shallow nature of the basin are considered to be the leading factors which have contributed to the development of the carbonate basin. The biogenic composition of the sediments in the channel is dominated by benthic foraminifera, followed by molluscs (pelecypods and gastropods) and corals.The mineralogy of the siliciclastic sediment is dominated by quartz, feldspar and hornblende. A possible source for the terrigenous sediments in the western part o, Härtill 5 uppsatser och Appendix 1-2