Late Saalian-Early Weichselian deposits in the Gulf of Riga (Kihnu Island) and Middle Weichselian deposits in NW Estonia (Vääna-J[otilde]esuu)

Abstract

The intertill deposits of the Kihnu Island in the Gulf of Riga, SW Estonia are according to their pollen content subdivided into two units: (1) the Late Saalian with a cold and drought-resistant pollen flora, and (2) the Early Weichselian with abundant redeposited Eemian pollen. Middle Weichselian interstadial deposits, overlain by till from the Late Weichselian stadial and underlain by the till from the Middle Weichselian, are known from the Vääna-Jõesuu site in NW Estonia. The erratic Holsteinian deposits at the Karuküla site, SW Estonia, previously dated as a Middle Weichselian Interglacial sediments, still complicate the Estonian till stratigraphy. According to the pollen content, the Late Weichselian late-glacial (Oldest Dryas, DR1) Haanja till in S Estonia cannot be correlated to the Late Weichselian till in N Estonia. Evidence for an Early Weichselian till is not known in Estonia.

Chronology of Late Saalian and Middle Weichselian episodes of ice-free lacustrine sedimentation recorded in the Arumetsa section, southwestern Estonia

“…On Kihnu Island brown silty-clayey deposits were described beneath the Eemian marine sediments at a depth of 34-40 m (-32 to -38 m relative to sea level) (Liivrand 1976;Raukas 1978;Kajak 1996). The sediment sequence in Core 21 in the Gulf of Riga (~ 17 km SSE from Kihnu Island) shows a (Funder et al 2002); 2, Peski (Miettinen et al 2002); 3, Põhja-Uhtju (Miettinen et al 2002); 4, Juminda (Kadastik et al 2003); 5, Prangli (Cheremisinova 1961;Kajak 1961;Liivrand 1987Liivrand , 1991; 6, Arumetsa (this paper); 7, Kihnu, Core 526 (Liivrand 1976(Liivrand , 1991(Liivrand , 2007; 8, Gulf of Riga, Cores 21 and 25 (Kalniņa 1997(Kalniņa , 2001; 9, Satiki (Kalniņa et al 2007); 10, Plašumi (Kalniņa 2001); 11, Grini (Kalniņa 2001); 12, Medininkai (Satkunas & Kondratienė 1998); 13, Pyshki (Shalaboda 2001;Litviniuk et al 2002); 14, Zhukevichi (Sanko et al 2002); 15, Dziewule (Bińka & Nitychoruk 2001); 16, Besiekierz (Mirosław-Grabowska 2009); 17, Studzieniec (Mirosław-Grabowska 2009); 18, Ruszkowek (Mirosław-Grabowska 2009); 19, Imbramowice (Mamakowa 1989;Mirosław-Grabowska 2009);20, Rzecino (Mirosław-Grabowska 2009); 21, Zeifen (Beug 1973); 22, Mondsee (Drescher-Schneider & Papesch 1998); 23, Klinge (Velichko et al 2005;Novenko et al 2008); 24, Gröbern (Wansa & Wimmer 1990;Litt 1994); 25, Lüneburger Heide (Behre 1962); 26, Brokenlande (Menke & Ross 1967); 27, Mommark (Kristensen & Knudsen 2006); 28, Anholt (Seidenkrantz 1993;…”

“…Late Saalian sediments and respective pollen assemblage zones were also distinguished in the sections on Põhja-Uhtju Island (Miettinen et al 2002) and the Juminda Peninsula (Kadastik et al 2003) in northern Estonia, both indicating open late glacial cold and dry conditions (derived from the presence of herbs Artemisia and Chenopodiaceae). Late Saalian siltyclayey deposits are found also on Kihnu Island (Liivrand 1976(Liivrand , 1991(Liivrand , 2007 in the Gulf of Riga, and in the coastal areas of Latvia (Kalniņa 1997(Kalniņa , 2001. On Kihnu Island brown silty-clayey deposits were described beneath the Eemian marine sediments at a depth of 34-40 m (-32 to -38 m relative to sea level) (Liivrand 1976;Raukas 1978;Kajak 1996).…”

“…Several marine and terrestrial records indicate a rapid Late Saalian (Saalian II, Warthe) deglaciation with gradual warming conditions (Mamakowa 1989;Bińka & Nitychoruk 2001;Funder et al 2002), others reflect a two-step event (called Zeifen-Kattegat oscillation), where warm conditions were interrupted by a cold dry oscillation preceding the Eemian Interglacial (Seidenkrantz 1993;Seidenkrantz et al 1996Seidenkrantz et al , 2000Beets et al 2006). In the northeastern Baltic region there are a number of sediment sequences (Peski, Põhja-Uhtju, Juminda, Prangli, Kihnu, Core 21 in the Gulf of Riga, Satiki, Plašumi, Grini) where, according to current knowledge (Cheremisinova 1961;Kajak 1961;Liivrand 1991Liivrand , 2007Kalniņa 2001;Miettinen et al 2002;Kadastik et al 2003), the end of the Late Saalian (MIS6) cold stage is represented by lacustrine sediments. The Late Saalian age of these, usually laminated silty-clayey deposits has been derived from their position under the Eemian strata.…”

“…The latter were recognized from the characteristic succession of pollen assemblage zones and occasionally from diatom analyses results (e.g. Kajak 1961;Liivrand 1987Liivrand , 1991Liivrand , 2007Kalniņa 1997Kalniņa , 2001Miettinen et al 2002;Kadastik et al 2003;Kalniņa et al 2007).…”

“…The absence of chronological data from the respective sequences may partly be due to the fact that most of the presumably Late Saalian and Eemian sediments were described and studied from core sections, which complicates the sampling for datings. The age control of the Late Saalian to Eemian sediment sequences has until now been based on the correlation of pollen and other micropalaeontological evidence with the NW European bio-and climate stratigraphies (Liivrand 1991(Liivrand , 2007Kalniņa 2001;Miettinen et al 2002).…”