Raně středověké říční koryto v blízkosti fortifikačního systému velkomoravského hradiska Pohansko u Břeclavi

Abstract

Geophysical, sedimentological, palynological, absolute-age dating and archeological techniques were used to study the deposits of the Early Medieval fluvial channel in the area of the Great Moravia Empire agglomeration Pohansko near Břeclav. Artificial profile situated on the base of ERT profiles and the archeological results led to opening of the fluvial channel. Newly documented fluvial channel erosively cut the complex of flood loams. Gravel lag covers the bottom of the channel and grade upwards into sandy channel infill with fining upward trend. Fluvial sandy dunes forming the most characteristic architectural element of the infill are represented mostly by trough cross-stratified medium-grained sands. These sands were penetrated by the piece of oak wood. Both the OSL dating of the sandy deposits and the dating of the oak wood (C14 and dendrochronology) point to the 9th century A.D. when the Great Moravia Empire was on its peak expansion. Active fluvial channel was probably used as a part of the fortification system and a possible wood bridge existed here in the front of the proposed Western Gate of the Pohansko agglomeration. Palynological studies reveal some fragmentation of the landscape and agricultural activities in the close surroundings. Deposits of the studied fluvial channel were covered by the beds of the younger flood loams.