【作者】 刘伟；

【导师】 沈晓华； 张玉广；

【作者基本信息】 浙江大学 ， 地质学， 2010， 硕士

【摘要】 大庆徐家围子位于松辽盆地北部地区,本文的主要研究目的是分析该地区地下水水性的分布特征,及其对油气藏形成的影响,从而预测该区油气分布规律及油气保存情况。通过大量研究资料说明,对油气聚集和保存最有利的环境,应是渗透水交替缓慢和停滞的环境。从现代水化学特征来看,这些地区是以C1-、Na+为主的高矿化水分布区。根据油气和油田水(实际是油层水)的渗滤和扩散作用,可以使浅层地下水、潜水、甚至地表水的化学成分发生变化,而具有了油田水的某些特征。这种作用在节理和裂隙比较发育的油气藏构造顶部和转折地带更容易发生。因此,在该区可以利用深层水的水化学资料或油田水特征在浅层水、潜水、甚至地表水中的这种效应,可以用来预测油气藏。通过研究得到,研究区地层水PH值在5.2-10.1之间,但大部分地区PH值大于7,水型整体呈NaHCO3型,部分井的个别深度段出现了Na2SO4、CaCl2、MgCl2水。松辽盆地北部深层在纵向上,随着地层深度的增加,地层水矿化度值逐渐增高,而氯钠系数及脱硫系数逐渐减小。徐家围子深层营城组地质构造复杂,各井间没有统一的气水界面,地层水中许多系数分布不均匀(如钠氯系数),水体是不连通的或连通性很差。地层水化学成分与天然气藏的形成和保存具有密切的关系,地层水总矿化度高值区、(钠氯系数、脱硫系数、碳酸盐平衡系数)低值区、氯镁系数高值区,最有利于天然气藏的富集和保存。工业气层、低产气层和非产气水层地层中的化学成分与气体产能有很好的对应关系。徐家围子深层主要目的层为营城组,其地层水矿化度值最高,钠氯系数及脱硫系数最小,地层水封闭性比较好,变质程度越来越深,处于比较强的还原环境,有利于油气的保存。更多还原

【Abstract】 Xujiaweizi of Daqing is located in north of Songliao Basin. The main research purpose of this article is to analyze the distribution characteristics of ground water and its impact on the formation of oil reservoir, thus predict the distribution and save of oil and gas in this area.The most favorable environment for oil and gas accumulation and save is the environment of infiltration water alternate slow and stagnates from a large number of information. These areas are high-mineralized water mainly with Cl-, Na+ from the view of modern water chemistry characters. Because of the percolation and diffusion of oil & gas and oilfield water (actually the water in reservoir), the chemical composition of shallow ground water, submersible water, and surface water have changed and have some characteristics of oilfield water. This effect is more prone to occur on the top of reservoir structure and turning zone with joint and cracks developed. So, we can use the water chemistry data of deep water or the effect of the oilfield water in shallow ground water, submersible water, and surface water to predict the formation of oil reservoir.Obtained from research, the PH value of the formation water in study area is between 5.2 and 10.1, but most of PH value are more than 7, water type is NaHCO3, section of the individual depth of some wells have water with Na2SO4、CaCl2、MgCl2.The deep of northern basin is in the vertical, with the stratum depth, the salinity values of the formation water increased gradually, however, the coefficient of sodium chloride and desulfurization coefficient decreases. The geological structure of deep Yingcheng formation in Xujiaweizi is complex, every well spacing didn’t have uniform air-water interface, many coefficients in formation water are nonuniform distribution (such as coefficient of sodium chloride), and water is not connected or very poor connectivity. Chemical composition of formation water has a close relationship with the formation and preservation of nature gas, the most beneficial environment for natural gas enrichment and preservation is the area of formation water with high salinity value, (coefficient of sodium chloride, desulfurization coefficient, carbonate equilibrium coefficient) low value area, high value area of coefficient of magnesium chloride. The chemical composition of industrial gas, low-yield gas and non-gas water formation layers have well relationship with gas production. The target layer in deep Xujiaweizi is Yingcheng formation, the value of mineralization in other layers is highest, the coefficient of sodium chloride and desulfurization coefficient is minimum, the formation water closure is better, the degree of metamorphism is more and more depth, in a relatively strong reducing environment, it is propitious to preserve the oil&gas.更多还原