Abstract The Tornquist Fan, reflecting the northern part of the Trans-European Suture Zone, comprises a series of fault zones and major single faults, striking mainly subparallel to the SW margin of the Fennoscandian Shield. The deep-seated faults of Wiek, Nord Jasmund and Schaabe, which cross the northern part of Rügen Island and areas of the adjacent Baltic Sea from NW to SE, originated in the late Paleozoic. They are accompanied by younger faults, especially in the Pomeranian Bay, that were formed by Mesozoic tectonic processes. Based on reprocessed offshore seismic lines east of Rügen, a polyphase evolution for the Wiek Fault System is proposed. It implies changes in the stress field since the Caledonian Orogeny. Crustal extension in the Middle Devonian led to the formation of basins along the SW margin of Laurussia. Subsequent compressional movements, induced by the distant Variscan Orogeny, resulted in segmentation and block faulting of the Rügen Basin prior to the late Carboniferous. These Paleozoic faults were reactivated by Mesozoic extensional stress regimes. In addition, new en echelon faults were generated, contemporaneously with the formation of the Western Pomeranian Fault System. Since the Late Cretaceous (Africa–Iberia–Europe convergence), selected major normal faults have been reactivated as reverse faults.

Abstract Based on reprocessed offshore seismic lines acquired during oil and gas exploration in the 1980s, we reconstruct the formation and reactivation of major fault systems in the southern Baltic Sea area since the late Paleozoic. The geological evolution of different crustal blocks from the Caledonian Avalonia–Baltica collision until the Late Cretaceous–Paleogene inversion tectonics is also examined. The detected fault systems occur in the northern part of the Trans-European Suture Zone (TESZ) and belong either to the late Paleozoic Tornquist Fan or to the complex Western Pomeranian Fault System (WPFS) generated during Mesozoic extensional movements. While the NW–SE-trending deep Wiek Fault separates the Arkona High from the Middle Rügen Block, the NNW–SSE-trending Agricola Fault demarcates the Middle Rügen Block to the Falster Block in the west. Together with the Plantagenet Fault and numerous younger faults in the Mesozoic cover, it forms the Agricola Fault System. Furthermore, structural analyses of the Prerow Fault Zone above the Prerow salt pillow and the Werre Fault Zone crossing the Grimmen High indicate a complex fault history.

Abstract The region of NW Russia connecting with the Baltic Sea presents a dynamic ecological system that was sensitive to environmental changes during the Holocene. Certain factors affected environmental changes in the region during the Holocene: deglaciation processes, that finally terminated about 9 cal ka BP; eustatic sea-level changes; and tectonic movements, which are basically considered in the region as isostatic uplift processes. Contextual remains of ancient human occupation sites can be the only evidence of surface stabilization in monotonous sediments, such as aquatic and subaquatic deposits. Prehistoric settlements also mark ancient shorelines. The latter is of great importance for studying the history of water oscillations and coastal-line displacements on the territory of NW Russia. The transgressive–regressive stages of the Baltic Sea (at c. 10.15 cal ka BP, the Ancylus transgression; at c. 7.6–7.0 cal ka BP, the Littorina transgression) have an impact on the positions of prehistorical sites. The complex investigations of the Stone Age archaeological settlements on the Karelian Isthmus and in the Dvina–Lovat’ basin, and their altitudes below sea level, allowed us to reconstruct palaeoenvironmental changes during the Holocene, the chronology of cultural–historical processes and the adaptation strategy of ancient people to environmental conditions in this territory.

Abstract We examine three questions concerning the post-glacial geological history of the eastern Gulf of Finland: (1) the amplitude of the Holocene sea-level regressions; (2) the time and mechanism of the development of large sand accretion forms (bars and spits), including dunes; and (3) the sea-level changes and coastal development over the last 4 kyr. Recent on-land geoarchaeological studies, as well as detailed marine geological research of the Gulf of Finland nearshore bottom, have provided new data for developing a hypothesis about the palaeogeographical development of the area. Geoarchaeological studies carried out around Sestroretsky Artificial Lake and within Okhta Cape, as well as analyses of previous studies of the Neolithic–Early Metal settlements, have shed new light on some aspects of coastal system development. Geographical information system (GIS)-based modelling of Holocene shorelines for the different time periods can be useful for future archaeological research. A series of submarine terraces was found at the bottom of the Gulf (sea depths from 10 to 2 m). The analysis of marine geological data (submarine terraces) and distribution of archaeological sites can be explained by a possible rise in relative sea level in the Gulf of Finland at 5 ka BP and a regression around 3 ka BP.

An accurate chronology for the exchange of aquatic species between water basins is important for paleoenvironmental reconstruction on both regional and continental scales. During the early Holocene, the range of zebra mussels, Dreissena polymorpha , was limited to the Black, Azov, Caspian, and Aral Seas, as well as the estuaries and lower and middle reaches of the Pontic-Caspian rivers. We present new findings that challenge the currently held view that this species migrated into the Baltic Sea watershed during the early 1800s through the canals joining the tributaries of rivers that drain into the Black and Baltic Sea basins. Geological investigations along the southeast Baltic Sea coast (Curonian and Vistula spits and lagoons) have uncovered shells of D. polymorpha that yielded radiocarbon ages older than 1000 radiocarbon yr B.P. We propose two scenarios to explain the new radiocarbon dates for D. polymorpha . The first scenario involves an anomalously large reservoir effect—as large as 600–800 yr—however, several lines of evidence cast doubt upon the validity of such a large reservoir correction. The second scenario that might explain the old zebra mussel ages is the earlier arrival of Dreissena polymorpha into the Baltic region. Natural exchange may have been facilitated by the proximity of the tributaries draining the Pontic and Baltic watersheds. Human-mediated transport is also considered in association with Viking voyages from the Baltic to the Black and Caspian Seas between A.D. 800 and 1000, and the riverine trade exchange during the Lithuanian expansion into the Pontic steppe in subsequent centuries. It is likely that both scenarios played a role, with implications for late Holocene biogeography and paleoecology of the Pontic-Caspian and Baltic basins.