Holocene environments of the high plateau, Yemen. Recent geoarchaeological investigations

The late Pleistocene and Holocene sedimentary stratigraphy is described for part of the high plateau of Yemen (altitude 2000–3000 m A.S.L.), to the south of Sana'a. The presence of angular slope debris and dune sand in pre-Holocene contexts suggest cold and arid late Pleistocene conditions, followed, after a phase of indeterminate semiarid fluvial activity, by the development of humic palaeosol A horizons at a wide range of altitudes. Dated to between 7500 and 4350 B.P., this palaeosol includes a valley floor component related to marsh and lake development. Correlation with the humid Neolithic phase of southern Arabia is suggested for this palaeosol. Above the palaeosol thick sedimentary accumulations are associated with increased evidence of human activity and the construction of terraced fields after around 4300 B.P.