Palaeomagnetic dating of the Grotta Romanelli (Apuglia, Italy) upper sedimentary filling: Insights on the Late Pleistocene-Holocene palaeoenvironment and human settings in the Mediterranean

Abstract

Situated along the Adriatic coast of southern Apulia (Italy), Grotta Romanelli (40.02o N, 18.43o E) is a natural coastal cave considered as a key site for understanding the Middle Pleistocene-Holocene geomorphological, palaeoenvironmental and stratigraphic evolution of the Mediterranean area. Its sedimentary fillings, extremely rich in archaeological and palaeontological findings have been long investigated for their stratigraphical and palaeontological aspects while efforts, mainly based on radiocarbon and pollen analyses, have been focused on better understanding their chronological framework. In this study, we propose a new age model based on the palaeomagnetic record of the uppermost Stratigraphical Unit IUS5 of Grotta Romanelli, also known as Terre Brune. Stepwise alternating field demagnetization provided well-defined directions, which were compared with the reference geomagnetic field curves calculated from the SHA.DIF.14k global geomagnetic field model directly at the cave’s geographic coordinates. A continuous age model was determined taking into consideration the principle of stratigraphic superposition. A selection of reliable, previously published, radiocarbon ages from animal teeth, bones and charcoal was also used for comparison. The proposed age-depth model covers the 14ka-8ka BP period, offering new insights on the chronology of the sedimentation and frequentation of the cave before its complete infilling. This chronological frame enables new considerations on the palaeoenvironmental evolution and climate changes that took place during the transition from the Late Pleistocene to the Holocene, and offers new insights on the dating of the Grotta Romanelli fossil remains, human rests and archaeological artifacts, including lithic tools and rock art.