松辽盆地梨树断陷苏家屯地区页岩气储层特征及含气性评价

Characteristics of shale gas reservoirs and evaluation of their gas potential in Sujiatun area, Lishu Fault Depression, Songliao Basin

宋振响 李忠博 张玺 周卓明 杨昊

Song Zhenxiang Li Zhongbo Zhang Xi Zhou Zhuoming Yang Hao

中国石化 石油勘探开发研究院 无锡石油地质研究所, 江苏 无锡 214126 2. 中国石化 东北油气分公司 勘探开发研究院, 长春 130062

Wuxi Research Institute of Petroleum Geology, SINOPEC, Wuxi, Jiangsu 214126, China 2. Exploration and Development Research Institute, SINOPEC Northeast Oil & Gas Branch Company, Changchun, Jilin 130062, China

页岩油气资源评价过程中除需对页岩作为烃源岩的特征进行评价外,更重要的是对其储层特征进行评价,尤其是可压裂性和含气性评价,直接涉及到资源的可动性。基于松辽盆地梨树断陷苏家屯地区苏2井营一段泥页岩系统取心和分析测试结果,开展了泥页岩生烃潜力评价、可压裂性及含气性评价。结果显示该区营一段泥页岩具备较好的页岩气生成条件。泥页岩脆性矿物含量高、杨氏模量高、泊松比低,压裂条件有利;孔隙度和渗透率普遍较低,但发育大量的天然裂缝和微裂缝,且压裂过程中容易产生形态较为单一的垂直裂缝,镜下还见到大量的微—纳米孔隙,主要以微孔和中孔为主,为页岩气提供了有利的运移通道和储集空间。该区多口探井在钻、测、录井的过程中均在营一段见到了良好的油气显示,并试获了高产气流,现场解吸显示泥页岩平均含气量达2.5 m3/t,显示出良好的资源规模及勘探开发前景。

In addition to the characteristics of source rocks, we should pay more attention to the evaluation of reservoir characteristics in shale oil and shale gas resource assessment, especially evaluation of fracturing and gas content which are directly involved in the mobility of resources.In this paper, we studied the hydrocarbon generation potential of mud shale as well as the fracturing properties and gas content on the basis of test results from the first member of Yingcheng Formation in well Su2 in the Sujiatun area of the Lishu Fault Depression.The results show that the mud shale from the first member of Yingcheng Formation have good shale gas generating conditions in this area.High content of brittle minerals, high Young's modulus and low Poisson's ratio make the mud shale easy to crack.The porosity and permeability of the mud shale are generally low, but there are a lot of natural fractures and micro-fractures;as well single vertical cracks are prone to form during the fracturing process.Beyond that, there are a lot of micro-nanometer pores under the electron microscope, mainly micropores and mesopores.All of these different scales of fractures and the availability of pores provide a favorable migration pathway and storage space for shale gas.During drilling, measurements and logging in the first member of Yingcheng Formation, many wells have shown a large amount of oil and gas;meanwhile, high-yield gas flows were obtained in wells Su2 and Li2.Field desorption tests showed that the averaged shale gas content in the first member of Yingcheng Formation in well Su2 is 2.5 m3/t, representing a considerable resource and a good exploration and development prospect.

国土资源部全国油气资源战略选区调查与评价专项(2009GYXQ15-07)资助。

https://doi.org/10.11781/sysydz201505606