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通过对渤海地区黄骅盆地中新生代火山岩进行典型的岩芯取样、岩相及全岩分析 ,并结合K Ar法测年、微量元素和同位素地球化学分析 ,得出以下结论 :主要岩石类型有新生代老第三纪玄武岩、中生代晚白垩世玄武粗安岩、中生代晚白垩世粗面英安岩和流纹岩和中生代早三叠世英安岩。晚中生代火山岩岩石的主量元素丰度呈双峰分布 ,从老到新 ,火山岩主元素中SiO2 减少 ,Fe2 O3、FeO、CaO、MgO、TiO2 、P2 O5、MnO有所增加。新生代玄武岩可能源自亏损的软流圈地幔 ,晚白垩世玄武粗安岩源自玄武质组分亏损和受到富集改造的岩石圈地幔 ,晚白垩世及早三叠世长英质火山岩可能源自地壳组分的部分熔融。
Through the typical core sampling, lithofacies and whole rock analysis of the Mesozoic-Cenozoic volcanic rocks in the Huanghua Basin in the Bohai Sea region, combined with the K-Ar dating, trace element and isotope geochemical analysis, the following conclusions can be drawn: The main rock types are newborn The Upper Cretaceous basaltic basalts, the Mesozoic Late Cretaceous basaltic rocks, the Mesozoic Late Cretaceous rough dacite and rhyolite, and the Mesozoic Early Triassic dacite. The main elemental abundance of Late Mesozoic volcanic rocks showed a bimodal distribution. From the old to the new, the content of SiO2 decreased and the contents of Fe2O3, FeO, CaO, MgO, TiO2, P2 O5 and MnO increased in the main volcanic rocks. The Cenozoic basalts may originate from the depleted asthenosphere mantle. The Late Cretaceous basaltic gabbros are derived from the depletion of basaltic components and lithospheric mantle under enrichment and remobilization. The possible sources of Late Cretaceous and Early Triassic volcanic rocks Part of the melting from the crust component.