ICDP workshop on the Deep Drilling in the Turkana Basin project: exploring the link between environmental factors and hominin evolution over the past 4 Myr

Abstract

Scientific drill cores provide unique windows into the processes of the past and present. In the dynamic tectonic, environmental, climatic, and ecological setting that is eastern Africa, records recovered through scientific drilling enable us to look at change through time in unprecedented ways. Cores from the East African Rift System can provide valuable information about the context in which hominins have evolved in one of the key regions of hominin evolution over the past 4 Myr. The Deep Drilling in the Turkana Basin (DDTB) project seeks to explore the impact of several types of evolution (tectonic, climatic, biological) on ecosystems and environments. This includes addressing questions regarding the region's complex and interrelated rifting and magmatic history, as well as understanding processes of sedimentation and associated hydrothermal systems within the East African Rift System. We seek to determine the relative impacts of tectonic and climatic evolution on eastern African ecosystems. We ask the follow questions: what role (if any) did climate change play in the evolution of hominins? How can our understanding of past environmental change guide our planning for a future shaped by anthropogenic climate change?

To organize the scientific community's goals for deep coring in the Turkana Basin, we hosted a 4 d ICDP supported workshop in Nairobi, Kenya, in July 2022. The team focused on how a 4 Myr sedimentary core from the Turkana Basin will uniquely address key scientific research objectives related to basin evolution, paleoclimate, paleoenvironment, and modern resources. Participants also discussed how DDTB could collaborate with community partners in the Turkana Basin, particularly around the themes of access to water and education. The team concluded that collecting the proposed Pliocene to modern record is best accomplished through a two-phase drilling project with a land-based transect of four cores spanning the interval from 4 Ma to the Middle–Late Pleistocene (< 0.7 Ma) and a lake-based core targeting the interval from ∼ 1 Ma to present. The second phase, while logistically more challenging due to the lack of drilling infrastructure currently on Lake Turkana, would revolutionize our understanding of a significant interval in the evolution and migration of Homo sapiens for a time period not currently accessible from the Kenyan part of the Turkana Basin. Collectively, the DDTB project will provide exceptional tectonic and climatic data directly associated with one of the world's richest hominin fossil localities.