Shoreline displacement and human resource utilization in the southern Baltic Basin coastal zone during the early Holocene: New insights from a submerged Mesolithic landscape in south-eastern Sweden

Abstract

Along parts of the Hanö Bay coast in south-eastern Sweden, remains of a submerged landscape can be found down to depths of almost 25 m b.s.l. The coastal landscape was formed during two periods of lowered water levels in the Baltic Basin: the Yoldia Sea and the Initial Littorina Sea stages. In order to reconstruct the local environment and shoreline displacement during the Yoldia Sea and Ancylus Lake stages, sediment sequences were obtained at 4.5, 17.5 and 18.7 m b.s.l. Detailed bathymetric mapping was based on multi-beam echo-sounding while surveillance and sampling of tree remains and archaeological findings were performed through diving. The Yoldia Sea low-stand reached its minimum level at 24–25 m b.s.l. just before 10,800 cal. BP. During the subsequent Ancylus transgression, a slow-flowing river passed through the area, accumulating thick deposits of fine-grained organic sediments in lagoonal basins. The river was surrounded by open woodland dominated by pine. Based on successive flooding of rooted tree stumps, the transgression rate was estimated at 4 cm·yr−1, until the Ancylus high-stand was reached at 5 m b.s.l. at 10,400–10,300 cal. BP. Findings of worked aurochs and beaver bones provide evidence of human presence in the landscape and show the importance of terrestrial resources for their subsistence. These integrated palaeoecological and archaeological investigations demonstrate the importance of submerged landscapes with well-preserved sediment, wood and bone material for our understanding of southern Baltic coastal landscapes and their inhabitants during the Early Mesolithic.

A new early Holocene shoreline displacement record for Blekinge, southern Sweden, and implications for underwater archaeology

“…based on findings of rooted tree stumps (Hansson et al . 2018a). An extrapolation was performed based on this level at Haväng and the corresponding level in the Arkona Basin (Bennike & Jensen ) in the southern part of the Baltic Sea.…”

“…The shoreline displacement record is based on interpolations and extrapolations of lowstand and highstand levels at Haväng (Hansson et al . 2018a), Arkona Basin (Bennike & Jensen ) and Olsäng (Mikaelsson ). Individually 14 C‐dated (cal.…”

“…; Berglund & Sandgren ; Hansson et al . 2018a). In the late 1800s De Geer () proposed that the Yoldia Sea lowstand reached down to at least 12 m b.s.l.…”

“…2017b), but in Swedish waters relatively few studies of submerged landscapes have been performed (Hansson et al . 2018a). These coastal areas were important for the dispersal of humans, technology and culture between landmasses, and offered attractive habitats for hunting, gathering and fishing (Harff et al .…”

“…; Kjällquist & Friman ) and a new shoreline displacement record from eastern Scania, slightly further south (Hansson et al . 2018a), provide baseline evidence for refinement and completion of the shoreline displacement history in Blekinge, which is of key importance in a wider perspective across the Baltic Basin.…”