Stratigraphic Evolution of the Turkana Basin, Kenya and Ethiopia

图尔卡纳盆地、肯尼亚和埃塞俄比亚的地层演化

• 批准号: 9117956
• 负责人: Craig Feibel
• 金额: $ 11.47万
• 依托单位: University of Utah
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1992
• 资助国家: 美国
• 起止时间: 1992-04-15 至 1994-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9117956&HistoricalAwards=false
• 关键词: Stratigraphic; Evolution; Turkana; Basin; Kenya

The Turkana Basin of Kenya and Ethiopia has long been known as a critical locality for the understanding of vertebrate evolution in East Africa. The geologic record of the basin spans a broad range, including Cretaceous through Holocene sediments with intercalated volcanics. Cretaceous through Oligocene history has yet to be characterized, but Miocene to Holocene strata are well- known. They record the stratigraphic evolution of the basin from a volcanically active, localized sediment trap, to an integrated fluvial basin with periodic lacustrine phases, and finally to a structurally-controlled rift basin. Research over the past decade on the context of vertebrate evolution in the basin has greatly altered our perspective on the history of the region and development of the East African Rift. Within the stratigraphic and temporal framework established for vertebrate studies, it is now possible to examine in detail the evolution of the region in terms of its volcanic, tectonic and sedimentary history, and to reevaluate the history of geologic processes in this portion of Africa. We intend to focus our attention on the unstudied southern portion of the Turkana Basin, and to investigate exposures in the Loiyengalani region, the Chalbi Desert, on Mt. Kulal, and in the Suguta and Kerio Valleys. Understanding of the geologic record from these regions is critical to evaluating the history of major geologic events in the basin, including basin integration, hydrographic connections, and structural development.

肯尼亚和埃塞俄比亚的图尔卡纳盆地长期以来一直被认为是了解东非脊椎动物进化的关键地点。 该盆地的地质记录涵盖范围广泛，包括白垩纪到全新世沉积物以及夹层火山岩。 白垩纪到渐新世的历史尚未确定，但中新世到全新世地层是众所周知的。 它们记录了盆地的地层演化过程，从火山活动的局部沉积圈闭，到具有周期性湖相的完整河流盆地，最后到结构控制的裂谷盆地。 过去十年对该盆地脊椎动物进化背景的研究极大地改变了我们对该地区历史和东非裂谷发展的看法。 在为脊椎动物研究建立的地层和时间框架内，现在可以详细研究该地区火山、构造和沉积历史的演变，并重新评估非洲这部分地区的地质过程历史。 我们打算将注意力集中在图尔卡纳盆地未经研究的南部地区，并调查 Loiyengalani 地区、Chalbi 沙漠、Kulal 山以及 Suguta 和 Kerio 山谷的暴露情况。 了解这些地区的地质记录对于评估盆地重大地质事件的历史至关重要，包括盆地一体化、水文联系和结构发展。