The Carboniferous-Permian sediments are distributed with eroded residual status under the Bohai Bay Basin; there were shallow intrusion rocks in the sediments with oil/gas. Through the geological and geochemical characteristic analysis on the distribution, main elements and trace elements in the intrusion rocks, the diorite porphyrites were richer in SiO2 and Na than that of the lamprophyres and both were rich in K and Mg for the intrusion rocks; the above rocks were very similar to the rocks of the same strata in Luxi uplift. The results showed that the intrusion rocks were formed because the earth upper mantle matter rose and intruded along the discordogenic fault at the beginning of Jurassic fault depression, and intruded in coal-series hydrocarbon source rocks in the form of magma rich in K with meta alkaline or meta neutral; the intrusion were small, and the ranges of roast on hydrocarbon source rock were less than the thickness of the intrusion, so that the intrusion had little influence on hydrocarbon generation from the coal-series hydrocarbon source rocks.%石炭系-二叠系沉积以剥蚀残余状分布在渤海湾盆地之下,在已发现油气的部位均发现浅层侵入岩.通过侵入岩产状、主量元素和微量元素组成等地质和地球化学分析,发现侵人岩主要为富二氧化硅、钠、钾和镁的闪长玢岩以及贫二氧化硅和钠、富钾和镁的煌斑岩,它们与鲁西隆起同层位侵入岩具有很多相似之处.研究认为它们是侏罗纪断陷形成初期上地幔物质上涌、沿深大断裂侵入形成的,以富钾偏碱性或偏中性两种岩浆侵入在煤系烃源岩中.研究还发现,煤系地层中的这些侵入体规模不大,对烃源岩的烘烤作用范围不超过侵入体的厚度,对整体的煤系生烃演化影响较小.
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