摘要
白垩系上统浦口组岩石组合分异明显,自下而上可分为四个岩性段,总体属于下粗上细,其中具有油气封盖意义的岩石是浦口组三段、四段的泥质岩,局部地区含膏盐岩。该套泥质岩是下扬子区中、古生界形成最晚的一套区域性盖层,由于印支—燕山运动的推覆、断隆、剥蚀等作用,使浦口组盖层与下覆不同层位的海相中、古生界呈不整合接触。在苏北盆地,浦口组泥质岩和膏盐岩具有厚度大、突破压力高的特征,是该区盖层发育与保存的有利地区。因此,作为区域性重要盖层之一的浦口组巨厚的泥质岩和膏盐岩,对下扬子区海相中、古生界的油气保存状况具有重要的意义。
The Pukou Formation of Upper Cretaceous has different rock assemblage, which can be divided into four lithologic sections from bottom to top. The cap rock is mudstone in third and fourth section of Pukou Formation, or gypsum - salt rock in local region. It is a set of regional caprock above Paleozoic and Mesozoic in the Lower Yangtze area. Due to nappe ,fault -uprising or eroding in Indosinian -Yanshanian movement, it was formed to an unconformity between Pukou Formation and various formations of Paleozoic and Mesozoic marine strata. In Subei Basin, the mudstone and gypsum - salt rocks of Pukou Formation have features of big thickness and high breakthrough pressure, which was significant to the hydrocarbon preservation of marine Paleozoic and Mesozoic in Lower Yangtze area.
出处
《复杂油气藏》
2010年第3期9-12,共4页
Complex Hydrocarbon Reservoirs
基金
江苏石油勘探局(JSG8804-07-ZS-0010-03)
关键词
下扬子区
浦口组
岩石类型
封盖能力
the Lower Yangtze area
Pukou formation
types of rock
sealing capacity
