Palynology and lithostratigraphy of Late Elsterian to Early Saalian aquatic sediments in the Ziemupe–Jūrkalne area, western Latvia

Abstract

Abstract This study is based upon lithological and palynological investigation of test-drilling cores along the Baltic Sea coast. Three intertill units of basin sediments are underlain by a thin layer of Lētiža (Elsterian) till and overlain by glaciotectonically deformed Kurzeme (Saalian Complex) till. The Kurzeme till differs from the Lētiža till by higher contents of limestone clasts and rounded hornblende grains. The lowermost intertill unit consists of glaciolacustrine to glaciomarine laminated clay of the Sudrabi member, a late glacial deposit of the Lētiža glaciation. Treeless vegetation covered the adjoining land. Next is the marine to brackish Akme n rags formation, deposited during the Pulvernieki (Holstenian) interglaciation. Thermophilous deciduous trees, spruce and alder dominated the forests during its climatic optimum. The youngest, dominantly sandy Jūrkalne formation was deposited in brackish- to freshwater at the beginning of the Kurzeme (Saalian Complex) glaciation, when land was covered by treeless vegetation. It contains a thin interbed of diamicton of Kurzeme till lithology suggesting a brief glacial advance in the Baltic Sea Basin at the beginning of the Kurzeme glaciation.