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1

Relative sea level changes and development of the Hiiumaa Island during the Holocene

Vassiljev J., Saarse L., Grudzinska I., Heinsalu A.

Geological Quarterly

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2015

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Vol. 59, No. 3

517--530

EN

Three sediment cores (Loopsoo, Tihu, Prassi) from Hiiumaa Island (Estonia) were investigated using diatoms, lithological proxies, magnetic susceptibility, geochronological dates and incorporated with the previously studied Kõivasoo site, aiming to reconstruct the development of the island and shoreline changes during the Litorina Sea and the Limnea Sea. The highest level of the Litorina Sea shoreline near Kõivasoo is at 27.6 m a.s.l., and it occurred during the Initial Litorina Sea. Within the Litorina Sea transgression, 7800 cal yr BP, relative sea level reached 24.9 m a.s.l. at Kõivasoo, 24.1 m a.s.l. at Loopsoo, 23.6 m a.s.l. at Tihu, and 21.5 m a.s.l. at Prassi. Kõivasoo became isolated from the sea about 8500 cal yr BP, Loopsoo between 7100 and 6800 cal yr BP, Tihu around 4800 cal yr BP, and Prassi about 2500 cal yr BP. Presently gained data from Hiiumaa Island confirm that the Litorina Sea regressed consistently during the last 8000 years due to progressively declining isostatic rebound. The present study is also illustrated by 3-dimensional palaeogeographic maps of the Hiiumaa Island development.

2

Deglaciation chronology of the Pandivere and Palivere ice-marginal zones in Estonia

Saarse L., Heinsalu A., Veski S.

Geological Quarterly

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2012

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Vol. 56, No 2

353-362

EN

Accelerator mass spectrometry (AMS) 14

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The history of the Yoldia Sea in Northern Estonia: palaeoenvironmental conditions and climatic oscillations

Heinsalu A., Veski S.

Geological Quarterly

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2007

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Vol. 51, No 3

295-306

EN

Late glacial and Early Holocene sediment sequences from North ern Estonia were investigated using diatom and pollen analysis and the accelerator mass spectrometry (AMS) 14C dating. The results of diatom analysis indicate that fresh water conditions prevailed during the initial and final phases of the Yoldia Sea in the investigated area. A near-bottom saline water current that penetrated into the Baltic Sea Basin during the brackish phase of the Yoldia Sea spread into the Gulf of Finland at ca. 11 300-11 200 calendar years BP. Coastal upwelling probably caused mixing of the water column and the circulation of brackish water up to the surface incertain near-shore areas in the Gulf of Finland. A slight change in the pollen composition may suggest deterioration in the climate and can be correlated to the Preboreal Oscillation. AMS 14C dates on aquatic plant macrofossils suggest a reservoir ef fect more than 1000 year for the brackish phase of the Yoldia Sea.