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基性岩墙群广泛出现在全世界前寒武纪地盾中 ,它的发育往往与区域性伸展构造环境有关 ,并可能与地幔柱有密切联系。前寒武纪出现的基性岩墙群以拉斑玄武质占绝对优势 (>80 % ) ,但在新太古代—古元古代高Mg的苏长质组分和苦橄质岩石也占重要位置 ,碱性岩类则相当稀少 ;而在新元古代碱性岩墙则变得很重要。基性岩墙群总体以富集LREE和大离子亲石元素为特征 ,其中在苏长岩中更为富集。基性岩墙群的岩浆有多种来源 ,其中苏长质岩浆主要来源于太古宙的陆下岩石圈 ,而拉斑玄武质岩浆多来源于主要由主体地幔组分 (PREMA)构成的地幔柱。地壳混染总体说来不是造成基性岩墙同位素及地球化学特征的主要机制。
The mafic dyke swarms occur extensively in the Precambrian earth shields throughout the world. Their development is often related to regional extensional tectonic settings and may be closely related to mantle plumes. The Precambrian basement dikes dominated tholei basaltic (> 80%), but they are also important during the Neo-Archean-Paleoproterozoic period with high-Mg permafrost and picrites Location, alkaline rocks are quite rare; and Neoproterozoic alkaline dikes become very important. The basic dyke swarms are generally characterized by enrichment of LREEs and large ion lithophile elements, of which, they are enriched in the latter. There are many sources of magma in the basic dyke swarm, in which the magmatic magma mainly comes from the Archean submarine lithosphere, whereas the tholeigen magmatic magma mostly comes from the mantle plume consisting mainly of the main mantle component (PREMA) . Crustal contamination in general is not the primary mechanism responsible for the isotopic and geochemical characteristics of the basic dyke.