Tazhong low salient is part of the foreland thrusting system in the southeastern Tarim Basin from Middle Ordovician to early Late Devonian. During this geologic period,the faults in Tazhong area were dominated by north-dipping and thrusts, and might intersected the deep north-thrusting major fault, forming a north-propagating wedge structure front. The low salient in Tazhong area experienced multistage tectonic movements, resulting in different structural geometries in different stratigraphic units. For example, NW-trending compressional fault-related folds dominate the Sinian-Ordovician structural layer;NE-trending negative flow structures and pull-apart grabens are predominant in the Silurian-Devonian structural layer; while positive flow structures and collapse structures resulted from magma invasion or diaper are prevalent in the Carboniferous-Permian structural layer. The early structures are commonly destroyed by the later structures duo to multistage faulting, making it difficult to identifying them on seismic section. Therefore, structure interpretation should be based on the seismic profiles with approximate the same vertical and horizontal scales, so as to correctly define the deformation features in these structural layers and extrapolate into areas where seismic data quality is low.%塔中低凸起是中奥陶世—晚泥盆世早期塔东南前陆冲断体系的一部分.这个时期塔中地区的断裂以北倾反冲为主,并可能与深部由南向北逆冲的主控断裂交汇,形成向北扩展的楔形构造前锋.塔中低凸起历经多期断裂作用,在不同地层单元内部形成了特有的构造形态,如震旦系—奥陶系构造层内主要发育北西向的挤压断层相关褶皱,志留系—泥盆系构造层内主要发育北东向的负花状构造和拉分地堑,石炭系—二叠系构造层内主要发育由岩浆刺穿或底辟形成的正花状构造和垮塌构造.多期断裂作用也造成了早期构造通常被晚期构造切割与破坏而在地震资料上难以识别的问题,构造解释工作应尽量在纵横比例相等的地震剖面上进行,以直观显示并准确识别这些构造层内部的变形形态,并从资料可信度高的位置入手,由已知到未知,逐步获得资料不好地区的断裂解释方案.
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