High resolution magnetostratigraphy and raio-isotope dating of early Pleistocene lake sediments from southern Armenia

The Pleistocene geology of Armenia is dominated by widespread occurrence of sediments recording recurring rapid and drastic changes of the environmental conditions during at least the last 2 million years. These sediments, predominantly diatomites, contain a huge variety of various fossil remains, allowing the reconstruction of flora, fauna as well as the climatic conditions especially during dispersal of early man into Eurasia 1.8 Ma. Radio isotope dating of pumice levels as well as a detailed magnetostratigraphic study have been carried out in Syunik Province near the town of Sisian, southern Armenia, in order to establish a temporal correlation of all major outcrops of paleo-lake sediments and to provide a timeframe for paleoenvironmental studies within this lake sediment succession.A total of 455 oriented drill cores was sampled at six large and four short sections with a sampling resolution between 5 and 20 cm. Detailed paleomagnetic experiments reveal the presence of a characteristic remanent magnetization (ChRM) pointing either to the north and down or south and up. A positive reversal test suggests the primary character of this magnetization component. Combining the normal and reverse polarity directions results in an overall sample mean direction of D = 354.8°, I = 51.5° with a Fisherian precision parameter k of 14.6 and the associated α