桂西晚古生代海相玄武岩的特征及其形成环境

广西西部广泛分布的基性岩，过去被认为是侵入的辉绿岩，晚古生代的基性熔岩只在泥盆系和下石炭统中零星分布，呈夹层产出，厚度不大。根据近年的野外工作，我们已经指出这些基性岩实际上是与晚古生代深水沉积共生的海相玄武岩，而不是象过去认为的大陆裂谷型玄武岩。玄武岩样品的地球化学分析结果表明，它们形成大洋板内构造背景，这证实了对古特提斯东延的设想，并有必要重新认识广西晚古生代地质演化的历史

Characteristics of the Late Paleozoic Oceanic Basalts and Their Eruptive Environments in West Guangxi

In west Guangxi, Late Paleozoic basic lava which were considered as the diabase, only scattered in Devonian and Lower Carbonaceous as interlayers with limited thickness. Recently, based on the field work we have recognized that those basic rocks actually were oceanic basalts intergrown with Late Paleozoic deep water deposits, rather than continental rift basalts. Geochemical analysis results of the basalts indicate that they were formed within oceanic plate. This supports our tentative assumption that the west Guangxi was the eastern part of the Paleo Tethys. It is necessary to reconsider the Late Paleozoic tectonic environments in Guangxi.