The Baringo Basin in Kenya is well known for its record of human evolution and of geological and environmental change through the last several million years. We focus on new explorations at Kilombe Mountain at the southern end of the basin, comparing its long term record with others in the region.
The Baringo Basin in the central Rift Valley of Kenya is well known for its record of human evolution and of geological and environmental change through the last several million years. The session focuses on the long Pleistocene records under investigation in various parts of the basin. New explorations around and especially in the caldera of Kilombe Mountain, an extinct volcano, are revealing its near continuous record through the Pleistocene. In the first part of the Pleistocene, there was a caldera lake at high level. Volcanic ashes deposited in and around it preserve exceptional traces of animal and early hominin activity, including Oldowan sites. The 100 metre geological sequence is the subject of continuing geological, geochemical and palaeonvironmental research. The southern flanks of the mountain preserve later sequences. These can be compared with the record in other parts of the Baringo basin, where for example the Chesowanja sequence provide other important evidence of hominin evolution including late appearances of Australopithecus boisei and an early Acheulean record. The Kapthurin Formation is especially important for its record through the period of modern human origins, also now represented at Kilombe. Other environmental research examines changes in vegetation within the Holocene. The session explores the overall contribution which this sector of the Rift Valley is making to studies of early human adaptations in environmental contexts susceptible to multi-disciplinary investigations. It shows the rare ability of this basin to preserve a high grade record from almost every period through the last two million years.