论文部分内容阅读
通过对松辽盆地徐家围子断陷营城组火山岩岩芯和薄片的观察,结合地震、测井资料,岩芯样品地球化学的测试数据和古地理背景,认为研究区内存在水下喷发作用形成的火山岩.松辽盆地徐家围子地区水下喷发火山岩的识别标志为沉凝灰岩与黑色泥岩互层、双层珍珠岩夹无斑或少斑流纹岩、膨润土和氧化系数(Fe3+/Fe2+).岩石类型有火山角砾岩、熔结角砾岩、珍珠岩、流纹岩、凝灰岩和沉凝灰岩,岩相以爆发相和喷溢相为主,水下喷发分布范围主要集中在汪家屯、升平、徐西、徐中和徐东等地区,以徐深1井区最为典型.研究区营城组火山岩上覆泥岩有机质丰度均值大于2.0%,为优质烃源岩,分析认为陆相水下喷发火山作用不仅为湖盆提供了丰富的矿物质和能量,使水体中有机质的含量增高,而且水体分异作用的产生,为有机质的保存提供了良好的还原环境,有利于优质烃源岩的形成,并据此建立了水下喷发与优质烃源岩形成的模式.
Based on the observation of the core and thin slices of the Yingcheng volcanic rocks in the Xujiaweizi Fault Depression, Songliao Basin, combined with the seismic data, logging data, geochemical data of the core samples and palaeogeographic background, it is concluded that underwater eruptions exist in the study area The volcanic rocks formed in the Xujiaweizi area of Songliao Basin are identified by the interbedded layers of sedimentary limestone and black mudstone, double-layer perlite with or without plaque rhyolite, bentonite and oxidation coefficient (Fe3 + / Fe2 +), The rock types are volcanic breccia, sinter breccia, perlite, rhyolite, tuff and tuff, and the lithofacies are dominated by eruptions and spouts. The distribution of underwater eruptions is mainly concentrated in Wangjiatun, , XuXi, XuZhong and Xudong etc., the most typical is Xushen-1 area.The organic matter abundance of the overlying mudstone of Yingcheng Formation in Yingcheng Formation is more than 2.0%, which is a high quality source rock. It is considered that the terrestrial underwater eruption volcano The role not only provides abundant mineral and energy for the lake basin, but also increases the content of organic matter in the water body and produces the differentiation of the water body, which provides a good reducing environment for the preservation of the organic matter and is favorable for the quality hydrocarbon The formation of source rocks and the formation of underwater eruptions and high quality source rocks are thus established.