Feldspar flotation as a quartz-purification method in cosmogenic nuclide dating: A case study of fluvial sediments from the Pamir.

Cosmogenic nuclide (CN) dating relies on specific target minerals such as quartz as markers to identify geologic events, including the timing of landscape evolution. The presence of feldspar in sediment samples poses a challenge to the separation of quartz and affects the chemical procedures for extracting the radioactive CNs Be and Al. Additionally, feldspar contamination reduces the Al/Al ratio, thus hinders the accurate determination of Al by accelerator mass spectrometry (AMS).

The age of the Lower Paleolithic occupation at Schöningen.

Thermoluminescence (TL) data are presented for eight samples of heated flint collected at the archaeological site of Schöningen 13/I-1 (Cycle I), for which a Holsteinian age is suggested by palynology of stratigraphically similar positions within a cyclic sedimentological model for the Quaternary sequence of Schöningen. Although the fire responsible for the zeroing of the TL-signal cannot be unequivocally attributed to human activities, any time difference between a natural fire and the human occupation is negligible for a site of this antiquity. The weighted mean age of 321 ± 16 ka places the last heating of the flints nominally in the age range of Marine Isotope Stages (MIS) 10 to 8.

Radiometric dating of the type-site for Homo heidelbergensis at Mauer, Germany.

The Mauer mandible, holotype of Homo heidelbergensis, was found in 1907 in fluvial sands deposited by the Neckar River 10 km southeast of Heidelberg, Germany. The fossil is an important key to understanding early human occupation of Europe north of the Alps. Given the associated mammal fauna and the geological context, the find layer has been placed in the early Middle Pleistocene, but confirmatory chronometric evidence has hitherto been missing.