【摘要】 位于松潘—甘孜造山带雅江穹隆群北东部的容须卡岩浆底辟穹隆区,经历了多期构造演化,内部构造极其复杂。为厘清容须卡地区岩浆与穹隆的演化关系,通过野外地质调查及室内综合研究,探讨了容须卡穹隆的地质特征及构造演化。该穹隆中心发育无根或肠状褶皱,及"S"型、"Z"型褶皱和"A"型平卧褶皱;穹隆外围发育叠加褶皱,反映造山带早期SN向和EW向收缩挤压。该穹隆主要经历了晚三叠世(印支末期)SN向与EW向的"双向挤压"作用;成穹期岩浆向上侵位时限为(214.4±1.2) Ma;成穹后经历了挤压推覆和应力松弛阶段;早中新世(17～10 Ma),由于青藏高原东南缘快速抬升,松潘—甘孜造山带发育NW-SE向鲜水河左旋走滑断裂,使容须卡地区形成一系列NNW向韧脆性和脆性破碎带。更多还原

【Abstract】 Rongxuka magma diapir dome is located in the northeastern part of Yajiang domes in Songpan-Ganzi orogenic zone, it has undergone multi-stage tectonic evolution, and the interior structure is extremely complex. In order to clarify the evolution relationships between magma and dome in Rongxuka area, the authors studied the geological characteristics and structure evolution of the dome on the basis of field geological survey and indoor comprehensive research. The rootless or ptygmatic folds in the center of the dome were well developed, as well as ’S-type’, ’Z-type’ folds and ’A-type’ recumbent folds. Superposed folds were developed in the periphery of the dome structure, which reflected that the orogenic zone was subjected to SN and EW biaxial compression in the early stage. Rongxuka dome has mainly underwent SN and EW biaxial compression in Indo-Chinese epoch or late Triassic. The time limited for the magma intruding upward to form the dome was(214.4±1.2) Ma. After the dome was formed, it went through the stages of extrusion nappe and stress relaxation. Owing to the rapid tectonic uplift of the southeastern margin of Tibetan Plateau during the early Miocene(17～10 Ma), the NW-SE sinistral strike slip faults of Xianshuihe were formed, which contributed to a series of NNW ductile and brittle fractured shear zones in Rongxuka area.更多还原