Mesozoic extensional brittle tectonics of the Arabian passive margin, inverted in the Zagros collision (Iran, interior Fars)
Mesozoic extensional brittle tectonics of the Arabian passive margin, inverted in the Zagros collision (Iran, interior Fars)
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阿拉伯被动边缘的中生代伸展脆性构造，在扎格罗斯碰撞中发生反转（伊朗，法尔斯内陆）
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发表时间：
2010
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影响因子：
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通讯作者：
É. Barrier
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作者：
P. Navabpour;J. Angelier;É. Barrier
现今伊朗西南部的扎格罗斯山带是新特提斯盆地南部的前东北阿拉伯被动大陆边缘，它起源于二叠纪-三叠纪裂谷作用，具有晚新生代碰撞叠瓦状构造。通过对法尔斯省高扎格罗斯带同沉积期正断层滑动资料的脆性构造分析，利用应力张量反演重建了中生代被动陆缘的伸展变形。这一重建揭示了两个主要的延伸方向，从北-南边缘倾斜的趋势发展到东北-西南边缘垂直的一个。考虑到基底构造和基底下寒武系盐拆离的存在，我们推断，一个transstensional伸展可能已经启动了两个主要时期的地壳拉伸：二叠纪-三叠纪厚皮阶段的基底断层发展的斜向裂谷，和中生代薄皮阶段的沉积盖层受到连续的伸展构造和块体倾斜。这种伸展构造历史可能在大陆碰撞之前的第三纪早期继续。断层滑动的几何形状和中生代伸展和晚新生代压缩的结构模式表明，在随后的薄皮和厚皮阶段的地壳缩短在扎格罗斯碰撞继承的结构反转。
Abstract The present Zagros mountain belt of SW Iran is known to be the former NE Arabian passive continental margin of the southern Neo-Tethyan basin, which originated by Permian–Triassic rifting, and has a late Cenozoic collisional imbricate structure. We carried out brittle tectonic analyses of syndepositional normal fault slip data in the High Zagros Belt of the Fars Province to reconstruct the extensional deformation of the passive margin during the Mesozoic era in terms of stress tensor inversion. This reconstruction revealed two main directions of extension, developing from a north–south margin-oblique trend to a NE–SW margin-perpendicular one. Considering the basement structures and the existence of the basal Infracambrian salt detachment, we infer that a transtensional extension could have initiated two major periods of crustal stretching: a Permian–Triassic thick-skinned phase with the basement faults developing in an oblique rifting, and a Mesozoic thin-skinned phase with the sedimentary cover being affected by successive extensional structures and block tilting. This extensional tectonic history probably continued during the early Tertiary period, prior to the continental collision. Fault slip geometries and structural patterns of both the Mesozoic extension and the late Cenozoic compression indicate inversion of the inherited structures in the Zagros collision during the subsequent thin- and thick-skinned stages of crustal shortening.