陆相页岩气成藏条件分析——以松辽盆地南部S洼槽为例

Accumulation conditions of shale gas in continental facies: taking S Depression of Songliao Basin as an example

赵静

ZHAO Jing

中国石油吉林油田分公司勘探开发研究院，吉林 松原 138000

Exploration & Development Research Institute, Jilin Oilfield Company, PetroChina, Songyuan 138000, China

松辽盆地南部S洼槽营一段发育的泥页岩是页岩气成藏的有利地质条件。文中通过分析S洼槽陆相页岩气藏特点和勘探成果认为，营一段为半深—深湖亚相，发育大套黑色碳质泥页岩和灰黑色泥岩。泥页岩有机碳丰度高，平均1.16%；有机质类型丰富，为Ⅱ1型、Ⅱ2型和Ⅲ型；成熟度为0.75%～1.17%，处于成熟热演化阶段。泥页岩储层孔隙度平均为3.71%，有机质孔发育，纹层状泥页岩内水平缝发育。泥页岩埋藏适中，累计厚度大，泥地比高，具备页岩气成藏的保存条件。泥页岩段总含气量较高，平均2.3 mg/g。脆性矿物质量分数高，平均71.3%，具有较好的可压裂改造性。多口探井测试资料表明，该区营一段下部气测显示好，其中sj1，sj3等井区存在一定规模的页岩气资源，具有良好的资源前景和勘探潜力。

The favorable geological condition for shale gas accumulation is found in the S Depression of Songliao Basin. This paper analyzes the continental shale gas characteristics and exploration achievements of the S Depression. It is considered that the shale of Ying 1 Section is mostly developed in semi-deep lake and deep lake sedimentary facies belts and has a large set of black carbonaceous shale and gray-black mudstone. The shale has high abundance of organic carbon with an average value of 1.16%, and the organic type is rich in Ⅱ1 , Ⅱ2 and Ⅲ. The maturity is 0.75%￣1.17%, which is in the stage of mature thermal evolution. The average porosity of the shale reservoir is 3.71%, the organic pores are rich in the shale reservoir, and the horizontal seams are rich in the stratified mud shale. The shale is moderately buried, which has a large cumulative thickness and a high mud-to-earth ratio. It has the storage conditions for shale gas accumulation. The total gas content of the shale section is relatively high, with an average value of 2.3 mg/g. The content of brittle minerals is high, with an average value of 71.3%, and it has good fissile reformability. The exploration well data of multiple drilling and testing show that the gas measurement in the lower part of the Ying 1 Section is good, and there are certain scales of shale gas resources in the well areas, such as Well sj1 and Well sj3, which have good resource prospects and exploration potential.

10.6056/dkyqt201903004