Microbial deposits commonly occur at the transition between carbonate and sulphate facies,and they also abound in the uppermost part of the middle Wuchiapingian Zechstein Limestone in west Poland.These deposits occur ...Microbial deposits commonly occur at the transition between carbonate and sulphate facies,and they also abound in the uppermost part of the middle Wuchiapingian Zechstein Limestone in west Poland.These deposits occur as isolated reefs of the basinal zone and in the condensed sequences in most parts of the study area.The deposits of the latter category reflect evaporative drawdown,and the abrupt boundary between the carbonate and sulphate deposits in the basin suggests the nature of evaporites that start to precipitate as soon as they reach the saturation level.A few-metre-thick unit of mostly brecciated microbial deposits at the top,reefal portion of the Zechstein Limestone records extreme palaeoenvironmental events that occurred at the transition from carbonate to sulphate deposition.These events are related first to subaerial exposure of the reef,which lasted several 10~5 years and then to the Lower Anhydrite transgression.展开更多
基金Grant No.DEC-2013/11/B/ST10/04949 to TMP from the National Science Centre(Narodowe Centrum Nauki)[research]Grant No.62.9012.1949.00.0(Polish Geological Institute-National Research Institute statutory funds)to TMP[final editorial work]。
文摘Microbial deposits commonly occur at the transition between carbonate and sulphate facies,and they also abound in the uppermost part of the middle Wuchiapingian Zechstein Limestone in west Poland.These deposits occur as isolated reefs of the basinal zone and in the condensed sequences in most parts of the study area.The deposits of the latter category reflect evaporative drawdown,and the abrupt boundary between the carbonate and sulphate deposits in the basin suggests the nature of evaporites that start to precipitate as soon as they reach the saturation level.A few-metre-thick unit of mostly brecciated microbial deposits at the top,reefal portion of the Zechstein Limestone records extreme palaeoenvironmental events that occurred at the transition from carbonate to sulphate deposition.These events are related first to subaerial exposure of the reef,which lasted several 10~5 years and then to the Lower Anhydrite transgression.
