Compositional and textural correlations between Olduvai Gorge Bed I tephra and volcanic sources in the Ngorongoro Volcanic Highlands, Tanzania

Geochemical correlations indicate that widespread ignimbrites and airfall tephra erupted from Ngorongoro during Olduvai lower Bed I time, reaching at least 40 km from source. Upper Bed I records a switch in NVH volcanic activity from Ngorongoro to Olmoti, coinciding with the first appearance of stone artifacts in the Olduvai record. Olmoti continued to supply pyroclastic deposits to the Olduvai Basin until the end of Bed I.