Petrology and geochemistry of rhizoliths from Plio-Pleistocene fluvial and marginal lacustrine deposits, east Lake Turkana, Kenya ( Koobi Fora Formation).

Recent studies of rhizoliths from the Koobi Fora Formation (Plio-Pleistocene) of east Lake Turkana, Kenya, indicate that their shapes vary with the depositional environment of their host sediment. Vertical rhizoliths are associated with channel-bar and overbank deposits of fluvial origin. Horizontal rhizoliths predominate in facies ascribed to beaches, lagoons, and floodplains associated with ancient Lake Turkana. The rhizoliths consist of sparry and micritic calcite cements whose petrography and geochemistry reflect differences in diagenesis between the two types of root systems.-from Authors