Upper Paleolithic Cultural Regression in the Mankyung River basin

This study focuses on the dark brown layer among the Paleolithic sedimentary layers identified in the Mankyung River basin, elucidating the transitional and regressive characteristics of the Late Paleolithic culture through natural scientific analysis and archaeological review. The Mankyung River basin, adjacent to the Geum, Seomjin, and Yeongsan River basins in southern Korea, is a crucial area where Paleolithic cultures of different regions intersect and overlap. The Paleolithic cultural layers here are classified into red-brown, dark brown, and light brown layers. The dark brown layer is an independent cultural layer characterized by a significant decrease in lithic artifact quantities and a dominance of simpler lithic technologies centered on quartz materials. Natural scientific analyses indicate that the dark brown layer formed approximately 20,000 to 25,000 years ago during Marine Isotope Stage 2 (MIS 2) ‘Cold-1·2’ period, just before the Last Glacial Maximum (LGM), under cold and dry climatic conditions. This layer exhibits soil structures rich in clay and silt, features such as soil wedges, and reduced magnetic susceptibility reflecting climate deterioration. These environmental changes worsened the living conditions for Paleolithic humans, leading to simplified lithic manufacturing, reduced long-distance raw material acquisition, and a restricted range of group movement. The drastic reduction in lithic quantity and uniformity during this period reflect cultural decline due to environmental stress and survival pressures. While the preceding red-brown layer shows advanced blade technology using rhyolitic materials, such technologies are absent in the dark brown layer, which is dominated by simple lithic toolkits comprising quartz-based scrapers and choppers. The subsequent light brown layer shows a technological recovery with more refined Late Paleolithic lithic technologies. Thus, the Paleolithic culture in the Mankyung basin experienced cycles of growth, decline, and recovery in response to climatic fluctuations. The dark brown layer represents a significant geological, climatic, and cultural turning point, not merely a straightforward cultural collapse but an adaptive strategy to extreme climatic conditions such as periglacial environments. This study reinterprets Late Paleolithic cultural changes on the Korean Peninsula based on the Mankyung basin, emphasizing the need for scientific verification and comparative regional studies of the dark brown layer. These efforts will contribute to a more comprehensive understanding of the persistence, interruption, and complex dynamics of Paleolithic cultural change

Glacial period · Holocene · Last Glacial Maximum · Marine isotope stage · Middle Paleolithic · Paleolimnology · Paleosol · Upper Paleolithic · Varve · Geological formations and processes · Geology and Paleoclimatology Research · Pleistocene-Era Hominins and Archaeology