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毕机沟侵入体作为扬子克拉通北缘已知分布面积最大的镁铁质－超镁铁质侵入岩体，在扬子克拉通岩石圈演化研究中具有重要地位。除在七十年代开展过部分矿产资源调查工作外，长期缺乏深入研究。本文在Ｓｍ－Ｎｄ和Ｒｂ－Ｓｒ年代学工作基础上厘定了毕机沟侵入体的侵位和后期构造热事件时代；根据侵入体源区地幔组成特征和地幔端元组成，显示出毕机沟岩体源区具有与大陆岩石圈脱层作用有关的成因信息，结合晚元古代扬子克拉通北缘在构造体制、幔源岩浆性质和地壳增生方式等发生突变的地质背景以及现代大陆岩石圈脱层作用研究成果，提出了区内新元古代可能存在大陆岩石圈脱层作用的初步认识
As the mafic-ultramafic intrusive rock with the largest distribution area known in the northern margin of the Yangtze craton, the Bijicao intrusive body plays an important role in the study of the evolution of the Yangtze cratonic lithosphere. In addition to carrying out part of the mineral resources survey in the seventies, the long-term lack of in-depth study. Based on the Sm-Nd and Rb-Sr chronological work, the emplacement of the Peridot invades and the post-tectonic thermal events were determined. According to the composition of the mantle and the composition of mantle plume, The source rocks of the pluton have the genetic information related to the delamination of the continental lithosphere. Combined with the geological background of the tectonic regimes, the mantle magmatism and the crustal hyperplasia, the northern margin of the Yangtze craton in late Palaeozoic, Layer effect research results, put forward a preliminary understanding of the Neoproterozoic continental lithosphere delamination may exist