Heterogeneity of folding in Zechstein (Upper Permian) salt deposits in the Kłodawa Salt Structure, central Poland

Abstract

Anal y sis of folds car ried out in the K³odawa Salt Struc ture (cen tral Po land) showed that the Up per Perm ian (Zechstein) siliciclastic-evaporitic suc ces sion is het er o ge neously folded, re sult ing from dif fer ences in bed com pe tence and stra tig ra phy. Rock salt and pot ash-rich suc ces sions of each Zechstein cy cle are in ter nally folded and con tain mul ti ple sheath folds, orig inated dur ing lat eral flow of salt at an early stage of de for ma tion. These folds have been re folded by up right sheath folds within thick PZ1-PZ2 rock salt com plexes. The lack of superposed folds in PZ3-PZ4 salt com plexes and un con formi ties between the PZ1-PZ2 and PZ3-PZ4 units in di cate that the rock salt beds were in ter nally folded prior to diapirism, in de pendently in each salt bed. The PZ1-PZ2 rock salt beds welded dur ing lat eral flow and were folded to gether into up right sheath folds dur ing the up ward flow of salt. These superposed folds clus tered into subordinary diapirs and pierced through the younger de pos its. The lat ter sunk in salt masses to form large-scale synclinoria, the strata of which con tain early tec tonic and weakly de formed sed i men tary struc tures.

Long Term Analysis of Deformations in Salt Mines: Kłodawa Salt Mine Case Study, Central Poland

“…1B) is part of the Izbica Kujawska-Łęczyca salt ridge which is the largest salt structure in Poland (Tarka, 1992;Burliga et al, 1995;Burliga, 2014). The salt dome is about 26 km long and about from 0.5 to 2 km wide and elongated in NW-SE direction.…”

“…The geological structure in the central and north-eastern part of the dome is more complex. Observations from mine galleries showed extremely complex internal deformations such as asymmetric folds, boudins, small-scale faults, veins and repetitions of the same lithostratigraphical units (Burliga, 1996(Burliga, , 2006(Burliga, , 2014Tarka, 1992).…”

“…The salt layers are covered by the gypsum-anhydritic-clay cap from the dissolution of the rock salt (residuum) and its thickness is from few to max. 250 m (Werner et al, 1960;Burliga 2006Burliga , 2014Burliga & Misiek, 1997;Toboła, 2016). Upward movement of salt and the structural evolution of the dome started in Triassic and continued till Tertiary (Krzywiec, 2004).…”

“…Upward movement of salt and the structural evolution of the dome started in Triassic and continued till Tertiary (Krzywiec, 2004). The internal structure of the dome is complicated as a result of deformations and different mechanical properties of rocks (Burliga, 2006(Burliga, , 2014Burliga & Misiek, 1997;Tarka, 1992). (after Garlicki & Szybist, 1986).…”

Inclusions in anhydrite crystals from blue halite veins in the Kłodawa Salt Dome (Zechstein, Poland)

“…Stud ies on the diapir struc ture in di cated its strong NW-SE elon ga tion. The length of the diapir is about 26 km, and its width var ies from 0.5 to 2 km (e.g., Werner et al, 1960;Tarka, 1992;Burliga, 2014;Burliga et al, 1995). The geo log i cal cross-sections show the asym met ri cal shape of the diapir: its NE slope dips mod er ately east ward at 55-70°, but its SW slope is al most ver ti cal.…”