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以前未被发现的辽西医巫闾山地区瓦子峪变质核杂岩主要由一条向西倾的低角度正断层———瓦子峪拆离断层组成 ,它将由早白垩世沉积岩和火山岩组成的上盘与糜棱岩化和未变形的下盘分开。瓦子峪拆离断层 (以前称之为孙家湾—稍户营子断裂 )位于变质核杂岩的西侧 ,倾角 10～ 4 0°,构造标志指示向北西方向 (约 2 90°)剪切。与早白垩世地壳伸展相伴生的下盘糜棱岩剪切方向也是北西向 ,这与瓦子峪拆离断层运动相关。已经发表的和未发表的锆石U Pb年龄、40 Ar/3 9Ar热年代学和上盘阜新盆地中生物地层的时代研究表明 ,地壳伸展和变质核杂岩形成时代为早白垩世 (约 12 7～ 116Ma)。我们未发现以前文献报道的医巫闾山是一对称的变质核杂岩的任何证据。瓦子峪变质核杂岩以及WNW侧的拆离断层的厘定会加深我们对华北克拉通早白垩世伸展作用的理解和认识 ,下一步的研究重点包括野外构造研究以确定拆离断层和下盘糜棱岩的空间展布 ,进一步采集样品以研究变质核杂岩的地质 /热年代学和变质核杂岩范围内的岩体成因。我们认为瓦子峪变质核杂岩的形成是太平洋板块边界重组、早白垩世岩浆作用致使地壳升温 ,从而导致经造山作用而加厚的地壳垮塌的结果。
The undiscovered Wazuyu metamorphic core complex in the Wulalu Mountain area of western Liaoning Province is mainly composed of a westward low angle normal fault --- Waziyu detachment fault. It consists of the Upper Cretaceous sedimentary rocks and volcanic rocks, Mylonitization and undeformed lower disc separate. Waziyu detachment fault (formerly known as the Sunjiawan-Slightly Yingying fault) is located on the west side of the metamorphic core complex and has a dip angle of 10 ~ 40 °. The tectonic flag indicates that the fault should be cut northwest (about 2 90 °) cut. The lower mylonite associated with the Early Cretaceous crustal extension is also NW-trending, which is related to the detachment fault movement in Waziyu. Published and unpublished zircon U Pb age, 40 Ar / 3 9Ar thermochronology and biogenic stratigraphy from the Upper Fuxin Basin indicate that the crustal extensional and metamorphic core complex was formed in the Early Cretaceous (about 12 7 ~ 116Ma). We did not find any evidence of the symmetrical metamorphic core complex in Mt. The determination of Wazhou metamorphic core complex and WNW detachment fault will deepen our understanding and understanding of the early Cretaceous extensional behavior of the North China Craton. The next research focus will include field structural studies to determine the detachment faults and footwall The mylonites were spatially distributed and samples were further collected to study the genesis of the geologic / pyrogenic geochronology and metamorphic core complex within the metamorphic core complex. In our opinion, the formation of the Wazhouyu metamorphic core complex is the result of the collapse of the Pacific plate boundary and the early Cretaceous magma that caused the crust to heat up, resulting in thickening of the crust by the orogeny.