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以褶皱和逆冲断层为主构造区的压力-温度(P－T)径迹可能是复杂的,在一个变质带内可能变化很大.P—T径迹的复杂变化,是由于褶皱作用和逆冲作用造成的热水平对流、变形期间及变形后发生的热传导,以及褶皱和逆冲断层内相对短时间的热驰豫所造成的.在褶皱区,可以观察到背斜与邻近向斜具有不同的P－T径迹,背斜内是冷却径迹,而向科内是加热径迹,这些不同P—T径迹是由于变形期间发生等温线的褶皱作用,变形后又发生等温线验豫所造成的.在多期变形褶皱区,非共轴褶皱作用造成变形带短距离(＜15km)内复杂的P－T径迹,这是因为在每个褶皱作用事件中,重复发生等温线的褶皱作用以及驰豫过程.在逆冲断层为主的构造区,大型逆冲席体的P一T径迹之间存在差异,因为在变形期间从较热的逆掩席体向较冷的下盘发生热传递.逆冲作用期间的热传递引起上盘冷却,下盘加热.在发育多重逆冲席体的地区,P－T径迹可能是复杂的,它将取决于逆冲席体间的热传递速率与逆冲断层发育的相对同步性.本文讨论的褶皱和逆冲断层地区所观察到的P一T径迹,记录了10~5~10~6年的相对短时间间隔.由于小尺度的热扰动会引起矿物平衡,在一个变质带的短距离内,P－T径迹可能变化很大.因此,将P－T径迹用于恢复构造历史之前,必须进行构造及岩石学的双重研究.
The pressure-temperature (P-T) track, which is dominated by fold and thrust faults, can be complex and may vary widely within a metamorphic zone. The complex changes in P-T track are due to the fold action and Convection of heat due to thrusting, heat conduction during and after deformation, and relatively short thermal relaxation within folds and thrusts In the fold zone, it is observed that the anticline has a The different P-T tracks are the cooling tracks in the anticlines and the heating tracks in the Coen. These different P-T tracks are due to the folds of the isotherms that occurred during the deformation, followed by the isotherms In the multi-stage deformed fold zone, the non-coaxial fold causes a complex P-T track within a short distance (<15km) of the deformation zone because the isotherm occurs repeatedly in each fold event In the tectonic zone dominated by the thrust fault, there is a difference between the P-T trajectories of the large-size mantle due to the transition from the hoter mantle to the colder Heat transfer occurs in the lower plate Heat transfer during the thrust action causes cooling of the upper plate and the lower plate Heating. In regions where multiple recoils are developed, the P-T path may be complex and will depend on the relative synchronicity of the rate of heat transfer between the thrust mat and the development of the thrust. The folds and The observed P-T track in the thrust area recorded a relatively short time interval from 10 to 5 to 10 to 6. Since small-scale thermal disturbances would cause mineral balance, within a short distance of a metamorphic zone, The P-T trace may vary widely, so a dual study of tectonics and petrology must be conducted prior to using the P-T trace to restore the tectonic history.