The Late Glacial and Early Holocene palaeoenvironmental changes recorded in landslide peat bog (landslide fen) deposits in the northern parts of the Polish Outer Carpathians (Southern Poland)

Abstract

In the northern part of the Polish Outer Carpathians, the Beskid Makowski Mts., four landslides formed during the Late Glacial have been identified so far. The landslide peat bogs  formed within landslide depressions represent specific type of minerogenic mires filled down by organic-minerogenic deposit. Within the depositional sequences of these peats, palaeoenvironmental changes of the Late Glacial and the Holocene are recorded. The oldest of the studied fens started to form in the Oldest Dryas, the younger ones – in the Bolling  (two peat bogs), Older Dryas and the Younger Dryas (Margielewski, 2003; Margielewski, 2006). In the sediments of the four landslide fens of the thickness varying from 4.5 m to 1.5 m, several logs were cored using the Instorf sampler. The laboratory study of the logs, reaching the deepest parts of the fens, included: palynological analysis, peat analysis (microscopic examination of organic deposits), grain-size (aerometric) analysis and content of minerogenic material (loss on ignition) analysis for 2.5 cm long intervals. Over 50 radiocarbon datings made in the studied logs (7-14 ones for each log), enable to date the horizons of lithological and pollen changes