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本文根据INDEPTH-Ⅳ剖面所做的地质、地球物理探测所取得的资料,进行综合研究,提出了一个新的昆仑山造山模式,论述了:(1)在早二叠世松潘—甘孜洋向昆仑—柴达木地块下俯冲使地块南缘形成陆缘弧和弧后拉张区,使昆仑—柴达木地块在持续碰撞挤压过程中,分别形成了造山带与古近—新近纪盆地的不同构造演化特征;(2)昆仑地段老结晶基底在地块对挤中不断向上抬升成山,同时又受到强烈剥蚀,使老结晶基底及深成岩呈现在地表;南昆仑地块则沿昆仑地块中央断裂向北逆冲到北昆仑地块之上,断裂深10 km;昆仑地块没有发生向北逆冲推覆到柴达木地块上;(3)昆仑地块地壳增厚主要发生在中地壳(6.2~6.6 km/s),是中基性岩石层的增厚;(4)柴达木盆地作为昆仑弧弧后拉张地带,随昆仑造山隆升而下沉,新生界陆相沉积达12~14 km厚,由“沉积”与“挤入”两个作用造成了地壳增厚;结晶基底发生断陷形成新裂谷,裂谷宽度约12 km,深度约4 km,导电带显示裂谷通过断裂与深部发生热流体联系;(5)再次确定了,柴达木盆地莫霍界面深52 km,昆仑山的莫霍界面深65~70 km,莫霍界面台阶位于格尔木附近(185 km距离处);(6)松潘—甘孜地体复理石层厚度为10~14 km,其下面的6.2~6.3 km/s均匀速度层(同时有高导电性显示)是本地块所特有,推测为残留洋壳的堆积,约15 km厚;浅层通过古近—新近系风火山推覆系增厚,另在中地壳部位挤入了15 km厚岩层;(7)否定了亚洲岩石圈地幔向柴达木地块地幔岩石圈之下俯冲的模式,提出印度大陆地幔岩石圈从高喜马拉雅下拆离成两层,并沿高原地壳底部向北伸展,直到中祁连山之下,成为高原南北对挤过程中岩石圈地幔长度调节的新方式。
Based on the data obtained from the geophysical and geophysical surveys conducted by the INDEPTH-IV section, a comprehensive study has been carried out to propose a new Kunlun orogeny model. The paper discusses: (1) In the Songliao-Garzê ocean to the Kunlun - Subduction under the Qaidam block resulted in the formation of continental margins and post-arc extension zones on the southern margin of the block. During the continuous collision and extrusion of the Kunlun-Qaidam block, the orogenic belts and the Paleo-recent (2) The old crystalline basement of Kunlun area lifts upwards into the mountain upwards in the block-to-surface extrusion and is strongly denuded at the same time, so that the old crystalline basement and plutonic rock are presented on the surface; the Kunlun block distributes along the Kunlun The central fault of the block thrusts northward to the North Kunlun block with a depth of 10 km. The North Kunlun block did not thrust northward onto the Qaidam block. (3) The crust thickening of the Kunlun block mainly Occurred in the middle crust (6.2 ~ 6.6 km / s), which is thickening of medium-basic rock layers; (4) Qaidam Basin, as the Kunlun arc back-tension zone, subsided with the uplift of the Kunlun Mountains, and the Cenozoic The continental deposition reached 12-14 km in thickness, resulting in thickening of the crust by the two actions of “deposition” and “squeezing in” The rift valley is about 12 km in width and about 4 km in width. The conductive zone shows that the rift is in contact with the deep hydrothermal fluid through the fault. (5) Once again, the Moho interface of the Qaidam Basin Depth of 52 km, the Kunluo Moho interface is 65-70 km deep, the Moho interface step is located near Golmud (185 km distance), and (6) the Songpan-Ganzi complex is 10-14 km thick The following 6.2 ~ 6.3 km / s uniform velocity (with high conductivity) is characteristic of the local block, presumed to be the accumulation of residual oceanic crust, about 15 km thick; shallow through the Paleogene - Neogene volcano push (7) Negate the subduction of the Asian lithospheric mantle into the lithosphere beneath the mantle of the Qaidam block, and propose that the lithosphere of the mantle in the Indian mainland should rise from high Himalayas into two under the detachment, and along the bottom of the plateau crust extends northward until the Qilian Mountains, a plateau north and south during the extrusion process of lithospheric mantle length adjustment of a new way.