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.

中文翻译：

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Jabłonna Reef (Zechstein Limestone) 的消亡和石膏沉积的开始（Wuchiapingian，波兰西部）：一个盐碱地巨岩中的碳酸盐到蒸发岩的转变

微生物矿床通常发生在碳酸盐岩和硫酸盐相的过渡带，在波兰西部的五家坪阶中泽希施泰因石灰岩的最上部也有大量的微生物沉积。这些沉积物作为盆地带的孤立礁体和研究区大部分地区的凝聚层序出现。后一类沉积物反映了蒸发下降，盆地中碳酸盐和硫酸盐沉积物之间的突然边界表明蒸发岩的性质一旦达到饱和水平就开始沉淀。在 Zechstein 石灰岩的珊瑚礁部分顶部有几米厚的大部分角砾岩微生物沉积单元记录了发生在从碳酸盐沉积到硫酸盐沉积转变的极端古环境事件。