烃源岩中不溶有机质：源于生物体的骨壁壳有机大分子

Insoluble organic matter in source rocks: derived from organic macromolecules in the skeleton, cell wall and shell of organisms

秦建中 潘安阳 申宝剑

QIN Jianzhong PAN Anyang SHEN Baojian

页岩油气富集机理与有效开发国家重点实验室, 江苏 无锡 214126 国家能源页岩油研发中心, 江苏 无锡 214126 中国石化油气成藏重点实验室, 江苏 无锡 214126 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

State Key Laboratory of Shale Oil and Gas Enrichment Mechanisms and Effective Development, Wuxi, Jiangsu 214126, China State Energy Center for Shale Oil Research and Development, Wuxi, Jiangsu 214126, China SINOPEC Key Laboratory of Petroleum Accumulation Mechanisms, Wuxi, Jiangsu 214126, China Wuxi Research Institute of Petroleum Geology, SINOPEC, Wuxi, Jiangsu 214126, China

结合超显微有机岩石学等技术的实验分析数据，从生物细胞分子构成及其稳定性的角度来探讨不同类型生物体骨壁壳有机碎屑与优质烃源岩中不溶有机质的关系。烃源岩中有机骨壁壳及其碎屑包括浮游藻类、疑源类、底栖藻类、真菌类和细菌类的细胞壁壳及其碎屑；浮游动物结缔组织的壳骨皮毛腱韧及其碎屑；水生植物及陆生高等植物的细胞壁和细胞骨架及其碎屑。对生物体起支持或保护作用的有机骨壁壳及其有机碎屑主要是由纤维素、几丁质、果胶、肽聚糖等无效碳水化合物和硬蛋白等非活性蛋白质构成，这些生物高分子化学结构稳定，不溶于有机溶剂和水，在优质烃源岩形成过程中以非脂类的不溶有机质形式保存下来，不具备生油能力，高成熟—过成熟早期可具有一定的生烃气能力，烃气转化率一般低于15%，约与Ⅲ型有机质或镜质组生烃能力相当。

Ultramicroscopic organic petrology analysis and other techniques were used to examine the relationships between organic detritus (from different types of biological skeleton, cell wall and shell) and insoluble organic matter in excellent source rocks from the point of view of molecular structure and stability of biological cells. Previous studies have shown that the organic skeleton, cell wall, shell and detritus in source rocks could be assigned to three main categories: (a) benthic algae, fungi, bacteria, pelagic algae and acritarchs; (b) shell, skin, hair and tendon as the connective tissue of zooplankton; (c) aquatic and vascular plants. The organic detritus playing the role of supporting or protecting the organisms were composed of inactive carbohydrate (e.g., cellulose, chitin, pectin, peptidoglycan) and inactive protein (e.g., scleroprotein). These biopolymers were chemically stable and insoluble in organic solvents and water. They were preserved in the form of insoluble organic matter (nonlipid) during the formation of excellent source rocks but without the ability to generate oil. They had hydrocarbon gas-generating capacity in the highly to early over-mature stage with a general conversion rate of hydrocarbon lower than 15%, which was equivalent to type Ⅲ kerogen or vitrinite.

国家科技重大专项 2017ZX05036-002;联合基金项目集成项目 U19B6003;国家自然科学基金项目 41690133;中国石化科技部项目 P19017-4

https://doi.org/10.11781/sysydz202006946