Collision and amalgamation of continent and microcontinent block were recognized as one of the major processes for building up a continent. The pre Jurassic structure of Northeast China and its adjacent region (inclu...Collision and amalgamation of continent and microcontinent block were recognized as one of the major processes for building up a continent. The pre Jurassic structure of Northeast China and its adjacent region (including south of Russia Far East, north of North Korea and inner part of southwest Japan) is characterized by collision and amalgamation of microcontinent blocks, such as the North China block (NCB), Northeast China block (NECB), Khanka block and Hida block.The central Jilin belt and Yanbian Grodekovsk belt that juxtapose and amalgamate these blocks in between in Northeast China and its vicinity were formed by a series of rock assemblages that are typical for Paleozoic active continental margin island arcs. The dominant Permian marine sequences in Yanbian (Yanbian Grodekovsk) belt, which are known for bearing transitional marine fauna, include turbidite olistostrome sediments of a slope facies, and limestones, sandstones as well as siltstones of a neritic littoral facies sediments along with predominant acidic to intermediate volcanic materials. The Maizuru belt in southwest Japan is supposed to be the equivalent of Yanbian Grodekovsk belt. The central Jilin belt consists of a well developed sedimentary sequence and volcanics of Paleozoic. The Bamiantong Gudonghe Fuerhe Chongjin suture complex in Northeast China and the equivalent Sangun Akiyoshi belt in southwest Japan serve as a major suture zone among these microcontinental blocks and belts.展开更多
On the basis of the synthetic studies of geology and geochemistry, an ophiolitic tectonic melange waa discovered in Sanligang-Sanyang area, the western part of Xiangfan-Guangji fault, the south margin of the Qinling O...On the basis of the synthetic studies of geology and geochemistry, an ophiolitic tectonic melange waa discovered in Sanligang-Sanyang area, the western part of Xiangfan-Guangji fault, the south margin of the Qinling Orogenic Belt. It is composed of different tectonic blocks with different lithological features and ages, mainly including the Huashan ophiolite blocks, Xiaofu Island-arc volcanic blocks, pelagic sediments, fore-arc volcanic-sedimentary system, and the massif of the basement and the covering strata of the Yangtze Block. These massifs were emplaced in the western part of Xiangfan-Guangji fault, the boundary between the Qinling Orogenic Belt and Yangtze Block, contacting each other by a shear zone or chaotic matrix. The characteristics of geochemistry indicate that the bash of the Huashan ophiolite are similar to mid-oceanic ridge basalts (MORB) formed in an initial oceanic baain, and the Xiaofu volcanic rocks are formed in a tectonic setting of island arc. The ophiolitic tectonic melange is the fragments of subduction wedge, which implies that there has been an oceanic basin between Qinling Block and Yangtze Block.展开更多
文摘Collision and amalgamation of continent and microcontinent block were recognized as one of the major processes for building up a continent. The pre Jurassic structure of Northeast China and its adjacent region (including south of Russia Far East, north of North Korea and inner part of southwest Japan) is characterized by collision and amalgamation of microcontinent blocks, such as the North China block (NCB), Northeast China block (NECB), Khanka block and Hida block.The central Jilin belt and Yanbian Grodekovsk belt that juxtapose and amalgamate these blocks in between in Northeast China and its vicinity were formed by a series of rock assemblages that are typical for Paleozoic active continental margin island arcs. The dominant Permian marine sequences in Yanbian (Yanbian Grodekovsk) belt, which are known for bearing transitional marine fauna, include turbidite olistostrome sediments of a slope facies, and limestones, sandstones as well as siltstones of a neritic littoral facies sediments along with predominant acidic to intermediate volcanic materials. The Maizuru belt in southwest Japan is supposed to be the equivalent of Yanbian Grodekovsk belt. The central Jilin belt consists of a well developed sedimentary sequence and volcanics of Paleozoic. The Bamiantong Gudonghe Fuerhe Chongjin suture complex in Northeast China and the equivalent Sangun Akiyoshi belt in southwest Japan serve as a major suture zone among these microcontinental blocks and belts.
基金Project supported by the National Natural Science Foundation of China (Grant Nos. 49773187, 49732080).
文摘On the basis of the synthetic studies of geology and geochemistry, an ophiolitic tectonic melange waa discovered in Sanligang-Sanyang area, the western part of Xiangfan-Guangji fault, the south margin of the Qinling Orogenic Belt. It is composed of different tectonic blocks with different lithological features and ages, mainly including the Huashan ophiolite blocks, Xiaofu Island-arc volcanic blocks, pelagic sediments, fore-arc volcanic-sedimentary system, and the massif of the basement and the covering strata of the Yangtze Block. These massifs were emplaced in the western part of Xiangfan-Guangji fault, the boundary between the Qinling Orogenic Belt and Yangtze Block, contacting each other by a shear zone or chaotic matrix. The characteristics of geochemistry indicate that the bash of the Huashan ophiolite are similar to mid-oceanic ridge basalts (MORB) formed in an initial oceanic baain, and the Xiaofu volcanic rocks are formed in a tectonic setting of island arc. The ophiolitic tectonic melange is the fragments of subduction wedge, which implies that there has been an oceanic basin between Qinling Block and Yangtze Block.
