| 摘要: |
| 通过低成熟度泥岩生排烃模拟试验,结合高压压汞、液氮吸附、核磁共振等测试手段,对鄂尔多斯盆地延长组长7泥岩的生油、储油、排油及热演化特征进行研究,对生成原油及其可动性进行分析,建立全过程演化模式。结果表明:长7泥岩最大的生油量出现在成熟度Ro=1.0%附近,生油量约为120 mg/g TOC,而后随着成熟度增高,生液态烃量逐渐降低,气态烃量逐渐增加,累积生烃量持续增大；排出页岩油量随成熟度增加呈现先升高后降低的趋势,在Ro为1.15%时液态烃排出量最大,约为64.55 mg/g TOC,之后随后成熟度继续增大,液态烃排出率迅速降低；随热演化程度升高,泥岩微孔体积持续增大,中孔体积先增大后减少,大孔体积先减小后增大,宏孔持续增大；可动流体饱和度先增大后减小再增大,不同成熟度泥岩可动流体平均为23.17%；长7泥岩生储排烃演化过程可划分为低成熟阶段、成熟—自饱和阶段、成熟—排油阶段、成熟—高成熟阶段4个阶段。 |
| 关键词: 鄂尔多斯盆地 页岩油 生排烃 可动流体 演化模式 |
| DOI：10.3969/j.issn.1673-5005.2024.02.004 |
| 分类号: |
| 文献标识码:A |
| 基金项目: |
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GE Yunjin, HE Yonghong, XU Jing, MA Fangxia, DU Kefeng, LI Hongjin
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(Reseach Institute of Shaanxi Yanchang Petroleum (Group) Company Limited, Xi 'an 710065, China)
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| Abstract: |
| Based on hydrocarbon generation simulation experiments, this study investigates oil generation, storage, and discharge, as well as the thermal evolution characteristics of the Chang 7 mudstone in the Ordos Basin. Through the integration of high-pressure mercury injection, liquid nitrogen adsorption, nuclear magnetic resonance, and other testing methods, the generated crude oil and its mobility was discussed, culminating in the establishment of a comprehensive evolution model for the oil . The findings indicate that the peak oil generation of Chang 7 mud shale occurs near a maturity level of Ro=1.0%, corresponding to approximately 120 mg/g TOC. Subsequently, as maturity increases, the quantity of liquid hydrocarbons gradually decrease while gaseous hydrocarbons show a gradual increase.The cumulative hydrocarbon generation continues to rise. The discharge of liquid hydrocarbons reaches its maximum (about 64.55 mg/g TOC) at a Ro of 1.15%. As maturity further increases, the discharge rate of liquid hydrocarbons decreases rapidly. With the increase of thermal evolution degree, the micropore volume of Chang 7 mud shale continues to increase, while the mesopore volume initially increases and then decreases. The macropore volume exhibits an initial decrease followed by an increase. The movable fluid saturation experiences an initial increase, followed by a decrease, and then another increase with increasing thermal maturity. On average, the movable fluid content in mudstone with varying maturity levels is 23.17%. Based on the data pertaining to hydrocarbon generation, expulsion, retention, pore evolution, and movable fluid, the evolution process of Chang 7 mudstone can be divided into four stages:low maturity, mature self-saturation, mature drainage, and mature-high maturity. |
| Key words: Ordos Basin shale oil hydrocarbon generation and expulsion movable fluid evolution model |
