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克拉通破坏的时间和范围是华北克拉通破坏研究的重要基础问题,但是在华北克拉通破坏时间与破坏范围的问题上存在着不同观点。本文通过对位于华北克拉通西北部银根—额济纳旗盆地苏红图坳陷内采集的火山岩进行年代学及地球化学研究,认为苏红图火山岩年龄为105~113 Ma,为一套钾质碱性系列玄武岩,其形成机制是由于岩石圈发生减薄,软流圈地幔岩浆上涌,经分离结晶而形成的,而动力学机制主要是由于西伯利亚板块、内蒙古褶皱带和华北板块在晚侏罗世发生的碰撞拼合。此外,本文还在前人对华北克拉通破坏研究基础上,依据作者对苏红图坳陷火山岩做的一些工作,粗浅地探讨了华北克拉通破坏的时间与范围的问题,认为华北克拉通周缘均为构造薄弱带,北缘为兴—蒙造山带,南侧为大别—秦岭造山带,东侧为苏鲁带和太平洋俯冲带,河套裂陷、汾渭裂陷分别与古元古代高温变质孔兹岩带及约18.5亿年前华北克拉通东、西部块体拼合时形成的中部造山带内位置大致重合,而苏红图坳陷位于中亚造山带南缘,同时也处于两板块拼合交汇处。这些构造薄弱带处在不同时期发生的俯冲与碰撞的结合部位,它们可能是岩石圈减薄的起始位置,并且它们的俯冲与碰撞时间是华北克拉通破坏的起始时间。克拉通破坏范围主要发生在太行山以东地区,太行山以西的河套裂陷、汾渭裂陷发生了减薄,而苏红图坳陷在早白垩世也发生减薄,所以,破坏范围分布在地理上呈不连续分布特征,造成这种分布特征的主要原因是由于不同区域的破坏时间与破坏的动力学机制不同。
The time and scope of the craton destruction are important basic problems in the study of the damage caused by the craton in North China. However, there are different views on the extent to which the damage and destruction of the craton in North China are destroyed. In this paper, the volcanic rocks collected in the Suhongtu depression of the Yingen-Ejin Basin in northwestern North China Craton have been studied for chronology and geochemistry. The volcanic rocks of the Suhongtu volcano are 105-113 Ma, Series of basalts are formed by the thinning of the lithosphere and upwelling of the mantle of the asthenosphere by separation and crystallization. The kinetic mechanism is mainly attributed to the fact that the Siberian plate, the Inner Mongolia fold belt and the North China plate in the Late Jurassic Collision occurred. In addition, based on the previous research on the destruction of the North China Craton and based on the author’s work on the volcanic rocks in the Suhongtu Depression, this paper also discussed the problem of the time and scope of the destruction of the North China Craton. They are all tectonic weak belts, the northern margin is the Xing-Meng orogenic belt, the south is the Dabie-Qinling orogenic belt, the east is the Sulu zone and the Pacific subduction zone, and the Hetao rift and the Fen-Wei rift are respectively connected with the ancient Paleoproterozoic high temperature Metamorphic khondalic belts and about 18.5 billion years ago, the eastern and western blocks of North China craton formed during the convergence of the central orogenic belt roughly coincide, while the Suhongtu depression located in the southern margin of the Central Asian orogenic belt, but also in two plates Fight the intersection. These structurally weak zones are located at the junction of subduction and collision occurring at different times. They may be the starting sites for lithospheric thinning, and their subduction and collision time are the onset time of the North China Craton. The extent of the cratonic damage mainly occurred in the area east of the Taihang Mountains and the Hetao rifts to the west of the Taihang Mountains. The Fen-Fen rifting thinned and the Su-Hong-Tu depression also decreased in the Early Cretaceous. Therefore, the extent of the damage was distributed in the geography Discontinuous distribution of the characteristics, the main reason for this distribution is due to different regions of the destruction of the destruction of the dynamic mechanism of time and different.