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中国东部中新生代盆—山系及有关地质现象,受水平挤压力和重力共同作用而呈正断层产出的上地壳平面X型断裂—压剪性正断层的控制,分别形成于晚保罗—早白垩世库拉板块北北西向挤压和晚自垩世以来印度板块北东向挤压时期。其断层上盘在重力作用下的受力状态和变形情况,类似于以中地壳塑性层为弹性基础、以断层面为自由端的悬臂梁,从而在该梁的弯矩和剪切力作用下,形成箕状断陷盆地。盆地基底在大幅度沉降过程中,把下伏中地壳塑性物质大量压向下盘,促使该盘上升为断隆山,使阴山、燕山、秦岭和太行山等山脉与断陷盆地毗邻。富含有用元素的中地壳高温塑性物质的上升,还产生了变质核杂岩、岩浆活动、成矿作用、高热流和地质灾害。
The Meso-Cenozoic basin-mountain system and related geological phenomena in the eastern China are dominated by horizontal crustal pressure and gravity, and are controlled by the normal crustal upper-crust X-fracture-compression shear normal fault formed by normal faults. Northwestern compression of the Kula plate of the Cretaceous and northeast extrusion of the Indian plate since the Late Cretaceous. Under the action of gravity, the stress state and deformation of the upper plate of the fault are similar to the cantilever beams whose elastic foundation is made of the plastic layer in the middle crust and whose free surface is the fault plane, so that under the action of bending moment and shearing force of the beam, Form a half-graben fault basin. During substantial subsidence, the basement of the basin pressed a large amount of plastic material in the underlying mid-crust to the lower plate, prompting the plate to rise up to a decadent mountain, so that mountains such as Yinshan, Yanshan, Qinling and Taihang Mountains are adjacent to the faulted basin. The rise of high-temperature plastic materials rich in useful elements in the crust also produced metamorphic core magmatism, magmatic activity, mineralization, high heat flux and geological disasters.