THE ZECHSTEIN STASSFURT CARBONATE HYDROCARBON SYSTEM OF THE THURINGIAN BASIN, GERMANY

The Thuringian Basin is the oldest hydrocarbon province in Eastern Ger many: wet gas and oil accumulations have been discovered since 1930. A fter a long inactive period of about twenty years, exploration for hyd rocarbons now continues with improved methods. Carbonates and evaporit es of the Permian Zechstein comprise the source, reservoir and seal fo r the main gas and oil play in the area. Today, they are buried less t han 1000 m deep over the major part of the basin. Modelling of the bur ial history of the basin indicates that up to 1500 m of Mesozoic strat a were eroded during a Late Cretaceous inversion event. peak hydrocarb on generation occurred just prior to this inversion, implying that hyd rocarbons have been effectively trapped in the reservoirs since that t ime. in addition, dry gas and nitrogen appear to have been sourced fro m pre-Zechstein intervals, which, with respect to nitrogen, poses a se vere exploration risk.