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华北克拉通存在3.8 Ga以上的地质演化历史。本文对近年来我们在鞍本、冀东、鲁西、胶东和阴山地区研究取得的进展作了简要介绍。在鞍山,深沟寺杂岩获得~3770 Ma,3600–3660 Ma,~3450 Ma,3310–3330 Ma和~3120 Ma锆石年龄,与白家坟杂岩和东山杂岩的岩浆事件十分类似。在冀东,对曹庄杂岩副变质斜长角闪岩和石榴黑云片麻岩定年,发现大量3.5–3.8 Ga碎屑锆石,并获得~2.5 Ga变质锆石年龄,冀东地区很可能存在始太古代岩石,可把曹庄杂岩形成时代限定在2.5 Ga和3.4 Ga之间。在鲁西,把太古宙基底从东北到西南依次划分为A、B、C三个岩带:A带主要为新太古代晚期的壳源花岗岩,B带主要为新太古代早期的岩石,C带主要为新太古代晚期的新生岩浆岩。鲁西是华北克拉通新太古代早期岩石分布最广泛的地区,也是华北克拉通确认新太古代早期和晚期表壳岩系共存的唯一地区。在胶东,规模巨大的2.9 Ga岩浆热事件被识别出来,它是强烈地幔添加作用的产物。可能作为岩浆板底垫托作用的结果,2.9 Ga岩石与2.7 Ga岩石一道,在新太古代晚期(~2.5 Ga)遭受强烈变质改造。在阴山地块,除2.5 Ga表壳岩和侵入岩外,还存在2.7 Ga英云闪长岩和2.6 Ga花岗岩。新获得的资料表明阴山地块与华北克拉通东部陆块具有类似的早前寒武纪地质演化历史。还对华北克拉通太古宙变质基底的锆石年龄和Hf同位素组成及全岩Nd同位素组成进行了统计研究。结合前人工作,初步总结了华北克拉通太古宙地质演化特点。认为华北克拉通与其它克拉通类似,新太古代早期—中太古代晚期是陆壳形成增生的主要时期,但最强烈广泛的构造热事件存在于新太古代晚期。在我们新提出的构造区划中,划分出了三个古陆块(>2.6 Ga),即东部古陆块、南部古陆块和中部古陆块。
North China Craton over 3.8 Ga geological evolution history. This article gives a brief introduction of the progress made in the research on sadan, Jidong, Luxi, Jiaodong and Yinshan areas in recent years. In Anshan, the zircons of the deep-seated complex rocks are ~ 3770 Ma, 3600-3660 Ma, ~ 3450 Ma, 3310-3330 Ma and ~ 3120 Ma, which are similar to the magmatic events of the Baijiafen and Dongshan complexes. In Jidong, the Paleogene amphibolite and pomegranate gneisses of the Caozhuang complex were dated and a large number of 3.5-3.8 Ga detrital zircons were found, and ~ 2.5 Ga metamorphic zircon ages were obtained. In the eastern part of Jidong There may be Paleo-Archean rocks that can limit the age of the Caozhuang complex to 2.5 Ga and 3.4 Ga. In Luxi, the Archean basement is divided into three types A, B and C from northeast to southwest: belt A is dominated by late Neo-Archean crustal granite, belt B is mainly the Neoproterozoic rock, C Belonging to the Neo-Archean Late Cenozoic magmatic rocks. Luxi is the most widely distributed Neo-Archean rock in North China Craton and the only area in North China where the craton confirms the coexistence of early Neo-Archean and late-crust rock series. In Jiaodong, the massive 2.9 Ga magmatic event was identified as a product of intense mantle addition. As a result of the magmatic plate underplating, 2.9 Ga rocks, along with 2.7 Ga rocks, were strongly metamorphosed during the Late Neo-Archean (~ 2.5 Ga). In the Yinshan block, in addition to the 2.5 Ga epikarst and intruded rocks, there are 2.7 Ga and 32 Ga granodiorites. The newly obtained data show that the Yinshan Block and the eastern part of the North China Craton have similar early Precambrian geological evolution history. The zircon ages, Hf isotopic composition and whole-rock Nd isotopic composition of the Archean metamorphic basement in the North China Craton were also studied. Combined with the work of predecessors, we initially summarized the geological evolution of Archean in North China Craton. It is considered that the North China Craton is similar to other craton. The Early Neo-Archean-Late Meso-Archean is the main period for the formation of continental crust. However, the most intense tectonic thermal event occurred in the late Neo-Archean. In our newly proposed structural division, three ancient continental blocks (> 2.6 Ga) are distinguished, namely the ancient eastern continental block, the ancient southern continental block and the ancient central continental block.