| 塔中地区志留系海相碎屑岩储层石英溶蚀成因及影响因素分析 |
| |
| 引用本文： | 万友利,丁晓琪,白晓亮,黄方方,朱志良.塔中地区志留系海相碎屑岩储层石英溶蚀成因及影响因素分析[J].沉积学报,2014,32(1):138-147. |
| |
| 作者姓名： | 万友利 丁晓琪 白晓亮 黄方方 朱志良 |
| |
| 摘 要： | 塔中地区志留系柯坪塔格组顶部不整合面附近沥青砂岩中发育大量因石英及次生加大边的溶蚀贡献的次生孔隙，根据薄片（铸体）观察、SEM观察显示石英溶蚀主要有3种赋存状态，其中对储层有建设性作用的溶蚀主要有石英硅质颗粒边缘的溶蚀及次生加大边的溶蚀两种，而对储层建设性作用不大的溶蚀为碳酸盐对石英及硅质的交代作用，这些SiO2的溶蚀路径可分为碱性环境和酸性环境下的SiO2溶解，统计表明碱性环境下的SiO2溶蚀普遍发育，但程度较低，而在酸性环境中溶解时对有机酸的种类、数量、流体性质、溶解环境中的流体能力以及地层温度的要求更为苛刻。本次研究中的酸性流体介质条件下的石英溶解即为古油藏破坏过程中受微生物降解烃类释放出大量的草酸起主要作用，因其降低了石英颗粒表面溶解反应的活化能，并在地层水中碱金属离子的“盐效应”作用下，大大提高了SiO2的溶解速率，溶解产物扩散到地层水中被带走，从而造成强烈的石英溶蚀现象，研究同时表明溶蚀程度强烈但具有很强的局限性。SiO2的溶蚀（解）作用能够提供一定量的油气富集空间，改善储层的物性，对在埋藏较深、时代较老的志留系海相致密碎屑岩储层中发育孔隙度较高的优质储层具有重要意义。
|
| 关 键 词： | 溶蚀机理 控制因素 海相碎屑岩 柯坪塔格组 塔里木盆地 |
Quartz Dissolution Causes and Influencing Factors in the Silurian Marine Clastic Reservoir Rocks in Central Tarim Basin |
| |
| Abstract: | A large number of secondary porosity due to quartz overgrowths dissolution, at the top of the Lower Sandstone the bituminous sandstone near the unconformity in Kepingtag Formation, in the Silurian marine clastic reservoirs in the central of Tarim Basin. By microscopic and SEM observation, dissolutions of SiO2 of sandstone reservoirs can be divided into 3 types, in which the reservoir constructive roles include quartz siliceous particles edge of dissolution and overgrowths dissolution, while carbonate replacement of quartz and silicon has little constructive. The path of the SiO2 dissolution path can be divided into the alkaline environment and acidic environment, statistics show that SiO2 dissolution generally in the alkaline environment of development, but the low level, dissolved in the acidic environment of the type of organic acids, the number of fluid properties, dissolved in fluid ability, as well as the formation temperature requirements are more demanding. Quartz dissolution under acidic fluid medium conditions in the study is the ancient reservoirs destruction process by microbial degradation of hydrocarbons releasing large amounts of oxalic acid plays a major role, because it reduces the surface of the quartz grains activation energy of the dissolving reaction, and formation water alkali metal ion salt effect role, which greatly improve the dissolution rate of SiO2 lysate spread into the ground water was taken away, resulting in a strong quartz dissolution phenomena, research also shows that the dissolution degree of strong but has a strong limitations. Dissolution of SiO2(solution) role is to provide a certain amount of space for oil and gas, and important significance to the deep clastic rocks in the Tarim Basin. |
| |
| Keywords: | |
| 本文献已被 CNKI 等数据库收录！ |
| 点击此处可从《沉积学报》浏览原始摘要信息 |
| 点击此处可从《沉积学报》下载免费的PDF全文 |
|
