墨西哥湾盆地中生界沉积特征分析

The Characteristics of Mesozoic Sediment of the Gulf of Mexico Basin

通过整理、分析国内外学者的研究成果,总结了墨西哥湾盆地中生代沉积特征。分析认为,墨西哥湾盆地晚三叠世主要发育河流相、冲积扇相及浅水湖相等陆相红层沉积;中侏罗世晚期-晚侏罗世早期广泛发育了盐岩沉积;晚侏罗世到白垩纪期间,盆地上倾方向发育河流和三角洲相,盆地周缘广泛发育滩坝及生物礁滩,下倾方向发育水下浊积扇和正常海相泥岩沉积。在对沉积特征分析的基础上,结合盆地的构造演化背景,建立了沉积演化模式,并分析了沉积模式及构造演化控制下的油气成藏模式。研究认为,礁相油气藏为研究区中生代的主要油气藏类型,此外,海底扇以及滑塌扇等深水碎屑砂体是油气富集的重要相带。

By analyzing the research results of internal and external scholars,the characteristics of Mesozoic sediments of the Gulf of Mexico Basin were summed up.Analysis indicated that in the late Triassic,fluvial facies,alluvial fan facies and shallow lake and the other continental facies were developed in the Gulf of Mexico Basin,and carbonate sediments were developed in the late period of middle Jurassic-the early period of late Jurassic.And from the later Jurassic to Cretaceous,the river and delta facies were developed in the updip direction,the beach bar and biological reef were developed widely around the basin,and in the downdip,the under water turbidite fen and normal marine mudstone sediments were developed.On the basis of studying the sedimentary characteristics,combined with structural evolutional background,a sedimentary evolution mode was established,and the sedimentary mode and the hydrocarbon accumulation pattern controlled by the structural evolution were analyzed.Study shows that the reef facies reservoir is the major type of reservoir in the Mesozoic System,in addition,the deepwater clastic sand bodies,such as submarine fan and slump fan are the important facies zones of oil and gas enrichment.