Paleosols as indicators for late Pleistocene landscape dynamics in Crete (Greece)

Abstract

Paleosols in different climatic zones and geomorphological settings serve as important paleoenvironmental archives. Crete (Greece) with its central location in the eastern Mediterranean area constitutes an important (paleo)climatic transition zone between northern Africa and the Eurasia. While paleosols have been commonly described and used as chronostratigraphic markers within a large number of geological and archaeological studies in Crete, they have not been subject of a comparative study so far. In the present study, we analyse seven pedocomplexes in central and western Crete within different climatic, geological and geomorphological settings. Our analysis is based on geochemistry, grain size distribution, bulk and clay mineralogy, micromorphology and absolute datings (luminescence, radiocarbon). In all cases, the paleosol horizons, mainly Bt- und Bk-horizons, display strong indications for pedogenesis, such as increased clay contents or carbon accumulation, similar reddish-brown colours and abundant characteristic clay minerals, especially vermiculite, smectite and kaolinite, compared to the over- and underlying sediments. However, clay composition also reveals desequilibrium conditions indicating an allochthonous origin of at least part of the material. Furthermore, micromorphological results do not clearly confirm in-situ pedogenesis. Therefore, open questions related to the redeposition of Terra Rossa as pedosediments as well as the importance of dust inputs from long-range sources remain. Chronostratigraphically, the timing of the deposition of soil parent materials as well as the formation of petrocalcic horizons indicate that soil formation was related to climatic transition phases during the late Pleistocene in most studied cases. However, due to the limited number of profiles, datings and comparable geo-archives in Crete, these results need to be substantiated in future studies incorporating further paleosols in Crete and the surroundings areas in the Eastern Mediterranean.

Keywords

• Pedogenesis
• Alluvial fans
• Pedosediment
• Clay mineralogy
• Calcrete
• Mediterranean paleosol