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麻粒岩作为一种高压、高温岩石,传统上认为其形成源于在大陆碰撞带和岩浆弧深处的变质作用。而近来,许多注意力都集中在大陆裂谷期间形成麻粒岩的可能性,特别是目前麻粒岩是否正在北美贝森和兰奇省之下形成。报道的新西兰菲奥德兰与上述情形相似,但它具有更深的剥蚀伸展区中的温压资料和单锆石U-Pb年龄。在新西兰菲奥德兰,早白垩的麻粒岩在岩浆增厚的大陆伸展滑塌之后已位于地壳浅层次中,它们再一次经历了麻粒岩相的变质作用。资料表明,麻粒岩相的变质作用可以出现在大陆伸展期间,并指出在新西兰西部,在高构造层次中,麻粒岩相的变质作用常伴随有一个或多个变质核杂岩的就位,这与在贝森和兰奇省提出的模式一致。
As a high-pressure and high-temperature rock, granulite was traditionally thought to originate from the metamorphism of the continental collision zone and magmatic arc. More recently, however, much attention has focused on the possibility of granulite formation during the continental rifting, and especially whether granulite is currently under formation in Beessen and Ranchi in North America. The reported Fiordland, New Zealand, is similar to the above scenario, but it has deeper tectonic-temperature data and single-zircon U-Pb ages in denuded zones. In Fiordland, New Zealand, the early-chalky granulites were located in the shallow crust following the extensional slip of the magma-thickened continent, once again experiencing granulite facies metamorphism. The data indicate that the metamorphism of the granulite facies may occur during the extension of the continent and indicate that metamorphism of the granulite facies is often accompanied by the presence of one or more metamorphic core complexes in the western part of New Zealand at high structural levels , In line with the model proposed in Besen and Lanch.