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苏鲁超高压带是否延伸到朝鲜半岛以及用何种方式延伸,成为很多地质学家注目的科学问题。新的研究成果包括:(1)在朝鲜半岛前寒武纪京畿陆块中,识别出一个含有榴辉岩的变质杂岩(洪城杂岩),榴辉岩透镜体出露于花岗片麻岩中,榴辉岩的锆石SHRIMP年龄是230Ma和～880Ma,围岩片麻岩的年龄约为810～820Ma;(2)朝鲜半岛的3个陆块(狼林、京畿和岭南陆块)具有与华北克拉通相似的岩石组合与演化历史;(3)南北朝鲜两个主要的古生代沉积盆地与华北具有很好的可比性;(4)临津江带和沃川带都不具有碰撞造山带的变质特征。据此提出了地壳拆离与逆冲模式,即华北与扬子陆壳的碰撞带沿朝鲜半岛西缘、大致呈南北走向分布。扬子陆壳俯冲带的深部(超高压部分)未在朝鲜半岛地表出露,下地壳(高压部分)从俯冲带拆离并逆掩到地表(洪城杂岩),以透镜体(岩片)状插入京畿地块的前寒武纪基底杂岩中,没有形成横穿朝鲜半岛的变质(造山)带。临津江带和沃川带有可能是扬子陆块的上地壳,它们从下地壳拆离、逆掩到地表,现在的展布状态是受到中生代构造的控制。
Whether or not the Sulu UHP belt extends to the Korean Peninsula and in what way extends it has become a prominent scientific issue for many geologists. The new research results include: (1) In the Precambrian Gyeonggi Land block of the Korean Peninsula, a metamorphic complex with eclogite (Hongcheng complex) was identified. The eclogite lens was exposed to granite In the gneisses, the zircon SHRIMP ages of eclogite are 230Ma and ~ 880Ma, and the age of gneiss in the surrounding rocks is about 810 ~ 820Ma. (3) The three land blocks of Korean peninsula (Wolfland, Gyeonggi and Lingnan land ) Have similar rock assemblages and evolutionary history with North China Craton; (3) the two main Paleozoic sedimentary basins in North and South Korea have good comparability with North China; (4) both the Imjin River and the Wawa River have no collision orogeny Belt metamorphic features. Accordingly, the crustal detachment and thrusting model is proposed, that is, the collision zone between North China and Yangtze continental crust is along the western margin of the Korean Peninsula and is generally distributed in a north-south direction. The deep (high pressure part) of the subduction zone of the Yangtze continental crust was not exposed on the surface of the Korean peninsula. The lower crust (high pressure part) was detached from the subduction zone and was inverted to cover the surface (Hongcheng complex) In the Precambrian basement complex in the Gyeonggi massif, no metamorphic (orogenic) belt across the Korean Peninsula was formed. The Imjinjiang belt and the Woochuan belt are probably the upper crust of the Yangtze block. They are detached from the lower crust and cover the surface of the earth. The current spreading status is controlled by Mesozoic structures.