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在高压、超高压变质岩出露齐全的西大别地区精确测制了一条比例尺为1∶1万的横穿造山带地质剖面。根据岩石组合、变质程度和变形样式,将剖面经过的区域从北到南划分出南湾、八里畈、浒湾、新县、红安、七角山、桐柏集和木兰山等8个岩石构造单元。区域构造变形解析表明,在西大别造山带剥露过程中,早期以多幕挤压褶皱和逆冲推覆变形占主导地位,晚期则主要表现为韧性伸展滑脱、正断和走滑改造。结合由榴辉岩推导的热结构特征,认为西大别造山带的基本构造样式是一个规模宏伟的、以超高压变质岩为核部并向西倾伏的不对称背形构造,后期的伸展滑脱使其发展成现今所展示的穹隆。
In the high pressure and ultrahigh-pressure metamorphic rocks reveal the complete range of West Dabie accurate measurement of a scale of 1: 1 Wan across the orogenic belt geological section. According to the rock assemblage, metamorphism and deformation pattern, the area passing through the section is divided into 8 rock structures of Nanwan, Balili, Huwan, Xinxian, Hongan, Qiaojianshan, Tongbaiji and Mulan Shan from north to south unit. Deformation analysis of the regional tectonic deformation shows that in the process of Xishan Dabie orogenic belts exhumation, multi-curtain extrusion folds and thrust nappe deformation predominated in the early stage, while ductile extensor slippage, normal fault and strike-slip transformation dominated in the late stage. Combined with the thermal structural features derived from the eclogites, the basic structural style of the Xishan Dabie orogenic belt is considered to be an asymmetric back-shaped structure with an ultra-high-pressure metamorphic rock as the core and a westward dip. Late extension Slippage has allowed it to develop into the dome that it shows today.