在豫西济源地区发现的陆相微生物成因构造(Microbially Induced Sedimentary Structures,MISSs),主要发育在孙家沟组和刘家沟组,可分为2大类即微生物席生长构造和微生物席破坏构造,8小类即生长脊构造、瘤状突起、曲形脱水裂痕、纺锤状脱水裂痕、似正弦状构造、树枝状脱水裂痕、多边形脱水裂痕和直脊状脱水裂痕.镜下分析显示具有大"U"形脊、定向排列的石英颗粒、近平行的暗色黏土矿物条带及悬浮排列的云母颗粒等微生物成因特征.通过与鲁山、黎城中元古界以及宜阳、柳林早三叠系微生物成因构造对比研究,认为研究区的微生物成因构造具有较为特殊的埋藏学特征,受二叠纪末灾变事件、适宜的沉积条件和气候因素控制,代表着研究区以微生物群落为主、后生动物稀少、植被贫乏、气候炎热和水土流失严重等特征的一种陆相灾后生态系.%We have firstly reported the presence of eight kinds of microbially induced sedimentary structures ( MISSs) or sedimentary surface textures, including growth ridges, growth postulas, curved desiccation cracks, spindle-shaped cracks,"Manchuriophycus" structures, dendritic desiccation cracks, polygonal desiccation cracks and desiccation cracks from the terrestrial upper Permian Sunjiagou Formation and lower Triassic Liujiagou Formation in Jiyuan west-ern Henan. Large U ridges, oriented sand quartz, mica grains and thin clayey laminae arranged parallel to bedding plane are the main features visible under the microscope. A series of evidence indicate that the Jiyuan MISSs are of bi-ogenic origin. Compared with MISSs of the Mesoproterozoic Yunmengshan Formation in Lushan, the Mesoproterozoic Changchougou Formation in Licheng, Lower Triassic Liujiagou Formation in Yiyang and Liulin, we concluded that mi-crobially induced sedimentary structures has special taphonomic characteristics and was controlled by the end-Permian mass extinction, sedimentary environments and climate factor in Jiyuan. MISSs of Jiyuan stands for terrestrial ecosys-tems following the end-Permian mass extinction with rich microbial community, scarce metazoan, poor plant, hot weather and serious soil erosion.
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