Late Paleozoic reefs and their significance for tectonics and oil-gas exploration in the Hinggan-Inner Mongolia area

作     者：TIAN ShuGang ZHANG YongSheng WANG JunTao NIU ShaoWu 

作者机构：Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China Institute of Mineral Resources Chinese Academy of Geological Sciences Beijing 100037 China Tianjin Institute of Geology and Mineral Resources China Geological Survey Tianjin 300170 China 

出 版 物：《Science China Earth Sciences》 (中国科学（地球科学英文版）)

年 卷 期：2011年第54卷第2期

页      面：212-222页

核心收录：

学科分类：081803[工学-地质工程] 08[工学] 0818[工学-地质资源与地质工程] 

基　　金：supported by the Geological Survey of China (Grant No. 1212010782004) National Natural Science Foundation of China (Grant No. 41072021) 

主　　题：reefs Late Paleozoic Hinggan-Inner Mongolia fold-zone oil-gas exploration 

摘      要：Many reefs of the Late Paleozoic have been discovered recently in the Hinggan-lnner Mongolia area. These reefs clearly are geographically extensive, and possess distinctive features and well-developed reef-facies. They have been found to contain five reef-building communities and were constructed in four periods. Colonial coral-algal reefs at Aohan and Chifeng represent a warm shallow-sea in the Carboniferous. Different reefs in the Xiwu Banner were formed in three periods： early Late Carboniferous, late Late Carboniferous and Early Permian. These reefs were built in warm sea conditions. Their buildup types include colonial coral frameworks, algae-buildings and lime-mud mounds. Bryozoan reefs in the Zhalaite and Dongwu banners were built in the late Middle Permian and thrived in a cold shallow-sea. All reefs grew independently on two kinds of sedimentary platforms, carbonate and carbonate-clastic mixed platforms. Four reef-forming periods occurred later from south to north, along a collisional course between the North China Plate and the Siberian Plate. These reefs can be arranged into three ＇reef-links＇ or reef zones that extend along plate margins. Among these, the Aohan-Chifeng reef-link indicates a northern margin of the North China Plate, the Zhalaite-Dongwu reef-link marks a southern margin of the Siberian Plate, and the Xiwu-Beishan reef-link reflects the former existence of some inter-plates. The strata of each reef-facies are thick and contain rich asphalt deposits. Overlapping and heteropic layers are very thick and contain dark oil/gas-rich horizons; TOC analyses verify that most of these are good hydrocarbon source rocks. This study shows that the study area is an excellent candidate for oil-gas exploration.