论文部分内容阅读
Based on high-resolution 2D seismic profiles,the Paleozoic structural deformation char-acteristics of Bachu (巴楚) uplift of northwestern Tarim basin,NW China,are exhibited in this article. The deformation happened during three main geological periods:the end of Middle-Late Ordovician (O2-3),the end of Early-Middle Devonian (D1-2),and the end of Late Permian (P2). In the Bachu uplift,there developed a series of NW-trending thrust faults and imbricate structures due to the effect of the NW-SE compression stress towards the end of Middle-Late Ordovician (O2-3) (middle Caledonian movement),and there developed some NNE-trending thrust faults and fault blocks under the control of the NEE-SWW compression stress at the end of Early-Middle Devonian (D1-2) (early Hercynian movement). However,at the end of Late Permian (P2) (late Hercynian movement),some NE-trending thrust faults and associated folds developed as a result of the NE-SW compression stress. The first-stage (O2-3) deformation is obviously more violent than those of the latter two stages (D1-2and P2),which implies that the Tarim plate drifted quickly to the north at around the same time basin.
Based on high-resolution 2D seismic profiles, the Paleozoic structural deformation char-acteristics of Bachu uplift of northwestern Tarim basin, NW China, are exhibited in this article. The deformation happened during three main geological periods: the end of Middle -Late Ordovician (O2-3), the end of Early-Middle Devonian (D1-2), and the end of Late Permian (P2). In the Bachu uplift, there developed a series of NW-trending thrust faults and imbricate structures due to the effect of the NW-SE compression stress towards the end of Middle-Late Ordovician (O2-3) (middle Caledonian movement), and there developed some NNE-trending thrust faults and fault blocks under the control of the NEE-SWW compression stress at the end of Early-Middle Devonian (D1-2) (early Hercynian movement). However, at the end of Late Permian (P2) (late Hercynian movement), some NE-trending thrust faults and associated folds developed as a result of the NE-SW compression stress. The first-stage (O2-3) deformation is o bviously more violent than those of the latter two stages (D1-2 and P2), which implies that the Tarim plate drifted quickly to the north at around the same time basin.