The Chinese Tianshan belt is a major part of the southern Central Asian Orogenic Belt, extending westward to Kyrgyzstan and Kazakhstan. Its Paleozoic tectonic evolution, crucial for understanding the amalgamation of C...The Chinese Tianshan belt is a major part of the southern Central Asian Orogenic Belt, extending westward to Kyrgyzstan and Kazakhstan. Its Paleozoic tectonic evolution, crucial for understanding the amalgamation of Central Asia, comprises two stages of subduction-collision. The first collisional stage built the Eo-Tianshan Mountains, before a Visean unconformity, in which all structures are verging north. It implied a southward subduction of the Central Tianshan Ocean beneath the Tarim active margin, that induced the Ordovician-Early Devonian Central Tianshan arc, to the south of which the South Tianshan back-arc basin opened. During the Late Devonian, the closure of this ocean led to a collision between Central Tianshan arc and the Kazakhstan-Yili-North Tianshan Block, and subsequently closure of the South Tianhan back-arc basin, producing two suture zones, namely the Central Tianshan and South Tianshan suture zones where ophiolitic melanges and HP metamorphic rocks were emplaced northward. The second stage included the Late Devonian-Carboniferous southward subduction of North Tianshan Ocean beneath the Eo-Tianshan active margin, underlined by the Yili-North Tianshan arc, leading to the collision between the Kazakhstan-Yili-NTS plate and an inferred Junggar Block at Late Carboniferous-Early Permian time. The North Tianshan Suture Zone underlines likely the last oceanic closure of Central Asia Orogenic Belt; all the oceanic domains were consumed before the Middle Permian. The amalgamated units were affected by a Permian major wrenching, dextral in the Tianshan. The correlation with the Kazakh and Kyrgyz Tianshan is clarified. The Kyrgyz South Tianshan is equivalent to the whole part of Chinese Tianshan （CTS and STS） located to the south of Narat Fault and Main Tianshan Shear Zone; the so-called Middle Tianshan thins out toward the east. The South Tianshan Suture of Kyrgyzstan correlates with the Central Tianshan Suture of Chinese Tianshan. The evolution of this southern domain remains similar from east （Gangou area） to west until the Talas-Ferghana Fault, which reflects the convergence history between the Kazakhstan and Tarim blocks.展开更多
Northward subduction of the Cenozoic Tethys ocean caused the convergence and collision of Eurasia-Indian Plates, resulting in the lower crust thickening, the upper crust thrusting, and the Qinghai-Tibet uplifting, and...Northward subduction of the Cenozoic Tethys ocean caused the convergence and collision of Eurasia-Indian Plates, resulting in the lower crust thickening, the upper crust thrusting, and the Qinghai-Tibet uplifting, and forming the plateau landscape. In company with uplifting and northward extruding of the Tibetan plateau, the contractional tectonic deformations persistently spread outward, building a gigantic basin-range system around the Tibetan plateau. This system is herein termed as the Cir- cure-Tibetan Plateau Basin-Range System, in which the global largest diffuse and the most energetic intra-continental defor- mations were involved, and populations of inheritance foreland basins or thrust belts were developed along the margins of an- cient cratonic plates due to the effects of the cratonic amalgamation, crust differentiation, orogen rejuvenation, and basin sub- sidence. There are three primary tectonic units in the Circum-Tibet Plateau Basin-Range System, which are the reactivated an- cient orogens, the foreland thrust belts, and the miniature cratonic basins. The Circum-Tibetan Plateau Basin-Range System is a gigantic deformation system and particular Himalayan tectonic domain in central-western China and is comparable to the Tibetan Plateau. In this system, northward and eastward developments of thrust deformations exhibit an arc-shaped area along the Kunlun-Altyn-Qilian-Longmenshan mountain belts, and further expand outward to the Altai-Yinshan-Luliangshan- Huayingshan mountain belts during the Late Cenozoic sustained collision of Indo-Asia. Intense intra-continental deformations lead ancient orogens to rejuvenate, young foreland basins to form in-between orogens and cratons, and thrusts to propagate from orogens to cratons in successive order. Driven by the Eurasia-Indian collision and its far field effects, both deformation and basin-range couplings in the arc-shaped area decrease from south to north. When a single basin-range unit is focused on, deformations become younger and younger together with more and more simple structural styles from piedmonts to craton in- teriors. In the Circum-Tibetan Plateau Basin-Range System, it presents three segmented tectonic deformational patterns： prop- agating in the west, growth-overthrusting in the middle, and slip-uplifting in the east. For natural gas exploration, two tectonic units, both the Paleozoic cratonic basins and the Cenozoic foreland thrust belts, are important because hydrocarbon in cen- tral-western China is preserved mainly in the Paleozoic cratonic paleo-highs and the Meso-Cenozoic foreland thrust belts, to- gether with characteristics of multiphrase hydrocarbon generation but late accumulation and enrichment.展开更多
基金supported by National Basic Research Program of China (Grant No. 2007CB411301)the Bureau of China Geological Survey (Grant No. 1212010611806)ISTO
文摘The Chinese Tianshan belt is a major part of the southern Central Asian Orogenic Belt, extending westward to Kyrgyzstan and Kazakhstan. Its Paleozoic tectonic evolution, crucial for understanding the amalgamation of Central Asia, comprises two stages of subduction-collision. The first collisional stage built the Eo-Tianshan Mountains, before a Visean unconformity, in which all structures are verging north. It implied a southward subduction of the Central Tianshan Ocean beneath the Tarim active margin, that induced the Ordovician-Early Devonian Central Tianshan arc, to the south of which the South Tianshan back-arc basin opened. During the Late Devonian, the closure of this ocean led to a collision between Central Tianshan arc and the Kazakhstan-Yili-North Tianshan Block, and subsequently closure of the South Tianhan back-arc basin, producing two suture zones, namely the Central Tianshan and South Tianshan suture zones where ophiolitic melanges and HP metamorphic rocks were emplaced northward. The second stage included the Late Devonian-Carboniferous southward subduction of North Tianshan Ocean beneath the Eo-Tianshan active margin, underlined by the Yili-North Tianshan arc, leading to the collision between the Kazakhstan-Yili-NTS plate and an inferred Junggar Block at Late Carboniferous-Early Permian time. The North Tianshan Suture Zone underlines likely the last oceanic closure of Central Asia Orogenic Belt; all the oceanic domains were consumed before the Middle Permian. The amalgamated units were affected by a Permian major wrenching, dextral in the Tianshan. The correlation with the Kazakh and Kyrgyz Tianshan is clarified. The Kyrgyz South Tianshan is equivalent to the whole part of Chinese Tianshan （CTS and STS） located to the south of Narat Fault and Main Tianshan Shear Zone; the so-called Middle Tianshan thins out toward the east. The South Tianshan Suture of Kyrgyzstan correlates with the Central Tianshan Suture of Chinese Tianshan. The evolution of this southern domain remains similar from east （Gangou area） to west until the Talas-Ferghana Fault, which reflects the convergence history between the Kazakhstan and Tarim blocks.
基金supported by the National Science and Technology Major Project of China(Grant No.2011ZX05003-002)
文摘Northward subduction of the Cenozoic Tethys ocean caused the convergence and collision of Eurasia-Indian Plates, resulting in the lower crust thickening, the upper crust thrusting, and the Qinghai-Tibet uplifting, and forming the plateau landscape. In company with uplifting and northward extruding of the Tibetan plateau, the contractional tectonic deformations persistently spread outward, building a gigantic basin-range system around the Tibetan plateau. This system is herein termed as the Cir- cure-Tibetan Plateau Basin-Range System, in which the global largest diffuse and the most energetic intra-continental defor- mations were involved, and populations of inheritance foreland basins or thrust belts were developed along the margins of an- cient cratonic plates due to the effects of the cratonic amalgamation, crust differentiation, orogen rejuvenation, and basin sub- sidence. There are three primary tectonic units in the Circum-Tibet Plateau Basin-Range System, which are the reactivated an- cient orogens, the foreland thrust belts, and the miniature cratonic basins. The Circum-Tibetan Plateau Basin-Range System is a gigantic deformation system and particular Himalayan tectonic domain in central-western China and is comparable to the Tibetan Plateau. In this system, northward and eastward developments of thrust deformations exhibit an arc-shaped area along the Kunlun-Altyn-Qilian-Longmenshan mountain belts, and further expand outward to the Altai-Yinshan-Luliangshan- Huayingshan mountain belts during the Late Cenozoic sustained collision of Indo-Asia. Intense intra-continental deformations lead ancient orogens to rejuvenate, young foreland basins to form in-between orogens and cratons, and thrusts to propagate from orogens to cratons in successive order. Driven by the Eurasia-Indian collision and its far field effects, both deformation and basin-range couplings in the arc-shaped area decrease from south to north. When a single basin-range unit is focused on, deformations become younger and younger together with more and more simple structural styles from piedmonts to craton in- teriors. In the Circum-Tibetan Plateau Basin-Range System, it presents three segmented tectonic deformational patterns： prop- agating in the west, growth-overthrusting in the middle, and slip-uplifting in the east. For natural gas exploration, two tectonic units, both the Paleozoic cratonic basins and the Cenozoic foreland thrust belts, are important because hydrocarbon in cen- tral-western China is preserved mainly in the Paleozoic cratonic paleo-highs and the Meso-Cenozoic foreland thrust belts, to- gether with characteristics of multiphrase hydrocarbon generation but late accumulation and enrichment.
