Environmental and tectonic significance of Late Permian reefs in the Linxi and adjacent areas in Inner Mongolia of China.59(7): 1463-1476
Environmental and tectonic significance of Late Permian reefs in the Linxi and adjacent areas in Inner Mongolia of China.59(7): 1463-1476
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内蒙古林西及邻区晚二叠世生物礁的环境与构造意义.59(7): 1463-1476
DOI：
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发表时间：
2016
期刊：
影响因子：
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通讯作者：
ZHU Changwei
中科院分区：
文献类型：
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作者：
TIAN Shugang;ZHANG Yongsheng;GONG Yuexuan;LI Zishun;GAO Li;a;ZHAI Daxin;ZHU Changwei
内蒙古林西县及邻近地区发现了许多晚二叠世高原边缘生物礁和礁丘。这些珊瑚礁证实兴安蒙古地区在晚二叠世是一个开阔、畅通无阻的海槽。通过对林西组四段、五段生物礁地层相、层序的研究，为重建林西—九台裂谷海槽的闭合过程，即抑制沉降、抬升和最终闭合提供信息。根据不同化石的范围或丰度，含礁地层的年龄已确定为晚二叠世末期。根据主要包括海绵、苔藓虫和钙质藻类的生物体的形态功能和古生态适应，区分了代表不同生态条件的六种造礁有机组合。根据组合，对林西组四段、五段陆架斜坡进行了缓坡和陡坡两种类型的解释。这些礁体的露头位置和类型界定了中朝地台的北缘，并确定了晚二叠世末林西—九台裂谷的隆升和最终闭合。
Many plateau-edge reefs and reef mounds of the Late Permian have been discovered in Linxi County and adjacent areas of Inner Mongolia, China. These reefs verify that the Hinggan- Mongolia Area was an open and unobstructed sea-trough in Late Permian. Facies and sequences of reef strata in Member 4 and Member 5 of the Linxi Formation were studied for information to reconstruct the closing process of the Linxi-Jiutai chasm in the sea-trough, i.e., to constrain subsidence, uplift, and final closing. Ages of the reef-bearing strata have been determined to be late and end of Late Permian, based on ranges or abundances of diverse fossils. Six reef-building organic assemblages were distinguished, representing different ecologic conditions, according to morphological functions and paleoecological adaptations of organisms including primarily sponges, bryozoans, and calcareous algae. Two types of shelf slopes, the gentle slope and the steep slope, have been interpreted for Member 4 and Member 5 of the Linxi Formation, based on the assemblages. The locations of outcrops, and types of these reefs delineate the north margin of Sino-Korea Platform, and define uplift and final closing of the Linxi–Jiutai chasm at the end of Late Permian.