The results of lithological, diatom analysis and radiocarbon dating of bottom sediments of small coastal lake basins along the Murmansk coast of the Barents Sea (the Kola Region, Russia) are presented. Sedimentary successions of two lakes reveal the presence of distinctive deposits, very different from the sediment above and below. These deposits are represented by erosional unconformity beds, gyttja and sand mixed with plant macrofossils, and characterized by changes in diatom flora and sand in a matrix of organic material. The sediments were deposited due to different catastrophic events: paleo-tsunami and paleo-earthquakes. According to radiocarbon analysis data, a tsunami occurred between 10,400–8200 cal yr BP and a paleo-earthquake occurred between 8200–7200 cal yr BP. We discuss various causes and mechanisms for the formation of disturbances in lake sediments, including the Storrega tsunami and paleo-earthquakes, which during and after deglaciation were strong and frequent.

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The paper presents isolation basin stratigraphy in bottom sediments from nine lakes in the Teriberka area on the Kola Peninsula, northwestern Russia. Isolation contacts in these basins, identified from lithological and diatom analysis, were used together with 25 radiocarbon dates, to construct a relative sea-level (RSL) curve for the Holocene. Records of marine water re-influx were found in the sediment sequence from one lake, located at c. 17 m a.s.l. The re-influx of marine water seems to be caused by the mid-Holocene (Tapes) transgression and tsunami event. The RSL curve indicates several phases in the postglacial evolution of the Kola coast. An early phase of rapid sea-level fall of c. 32 m around 11,500 cal yr BP, at a rate of c. 40 mm per year, corresponds to glacio-isostatically induced emergence following deglaciation at the Younger Dryas and beginning of the Holocene. In the time interval between c. 11,000 and 7600 cal yr BP, either a stillstand or a slight rise in relative sea level, cresting at about 21 m a.s.l., is suggested in the Teriberka area. This is followed, after c. 7300 cal yr BP to the present day, by a slow glacioisostatic emergence with an average rate of about 2–3 mm per year.