中上扬子地区海相成烃物质聚集分布规律及主控因素

以构造-层序地层学、沉积学与岩相古地理学理论和动态演化观为指导,通过新一轮中上扬子区震旦系-古生界成烃物质聚集分布规律分析,认为纵向上烃源岩与层序格架发育具有良好的对应关系,即对应于全球二级海平面变化旋回中的海侵体系域;主力烃源岩系以泥质烃源岩占绝对优势,次为碳酸盐质、硅质烃源岩,成层性好,单层厚度较薄;烃源岩母质类型和有机质演化随时代变新具有规律性变化;陡山沱组、筇竹寺组、龙马溪组和中上二叠统烃源岩品质较好,对油气成藏贡献大.横向上层序格架中各层烃源岩发育和分布规律及其有利区具有明显差异性;四川盆地内各层烃源岩全,江汉盆地下组合烃源层残存保留,雪峰西缘地区残存下组合烃源层,黔桂地区各套烃源岩相对较发育;以泥质烃源岩的分布范围最宽广,其层位、厚度和岩相最稳定,有机地化指标较佳.综合分析认为成烃物质聚集分布规律主要受构造背景、盆地性质、古气候、古地理以及沉积环境等因素控制,与各种成因引起的海平面上升的关系密切,并且总是聚集分布于滨海含煤体系、滞留陆棚、局限海湾、局限台地、台盆、大陆斜坡以及深水盆地等低能缺氧环境.

Distribution rule and main controlling factors of the marine facies hydrocarbon substances in the middle and upper parts of Yangtze region,China

Under the guidance of the tectonic-sequence stratigraphy,sedimentology and lithofacies palaeogeography and dynamic evolutionary view,the authors reappraise the distribution of the Sinian-Paleozoic hydrocarbon source rocks in the middle and upper parts of the Yangtze region.The vertical distribution of carbonate reservoirs is correlated well to the sequence stratigraphic framework,that is,to the transgressive system in the second order sea-level change cycle.The muddy source rocks are dominant in the main hy...