济阳坳陷深部热液活动与成岩成矿

The hydrothermal process and origin of illitation deeply in the Jiyang Depression

通常认为 ,沉积盆地中有机质热演化生烃和黏土矿物转化是埋藏深度加大的结果 ,温度升高是地热梯度的作用。深入研究济阳坳陷古近系发现 ,黏土矿物的转化是深部富烃、富碱、富金热液碱交代 (K+ 交代 )作用的结果 ,与此伴随的次生石英生成是碱交代过程中排硅的结果。许多证据表明济阳坳陷深部热液活动曾十分活跃 ,不仅提供热能 ,还提供重要的源物质 ,对油气藏形成和黏土矿物组合特征都有重大影响。我国东部裂谷盆地和西部克拉通盆地 (如塔里木盆地 )深部热液活动都十分活跃 ,重新认识深部热液活动与沉积盆地成岩、成矿作用的关系 ,将对油气勘探产生革命性影响。参 3

It is known that after the buried, thermal evolution, hydrocarbon generation of organic matter, kaolinite's transfer to montmorillonite, montmorillonite's transfer to illite, which coupled with hydrocarbon generation and migration. Investigation of the Paleogene sediments in Jiyang Depression of Sheng1i Oilfield showed that the transfer from montmorillonite, kaolinite into illite, montmorillonite into potash feldspar, sericite, illite is the result of K + metasomatism of deeper hydrothemol fluids, which associate with the generation of secondary quartz, and is the silicon release of K + metasomatism. In the Jiyang Depression there are some evidences of deeper hydrothermal fluids: gypsum salt generation, Paleogene reef and dolomization, anomalous high gold in crude oils, mantle derived CO 2 gas pool and 3 He isotopic anomaly, high temperature of quartz fluid inclusions, basalt magma effusive eruption, and so on. Recognition of illitation, dolomization, gypsum salt formation will bring about revolutionary effect on petroleum exploration in future.