塔中Ⅰ号坡折带上奥陶统礁滩的白云石化及其储集意义

作    者:郑兴平,寿建峰,朱国华,沈安江
单    位:中国石油杭州地质研究院
基金项目:
摘    要:
塔里木盆地塔中玉号坡折带上奥陶统良里塔格组礁滩灰岩发生了少量白云 石化作用。白云石化主要发育在溶洞充填的钙质渗流粉砂,泥晶生物碎屑灰岩的泥晶基质,亮晶颗粒灰岩的钙藻屑、藻砂屑、藻泥屑等三种组构中。白云石化直接贡献了平均1%的孔隙度,同时产生的白云石晶间孔为进一步溶蚀提供了通道,对有效储层的形成起到了重要作用。高镁方解石生物是白云石化所需镁离子的重要来源。这套与生物白云石化相关的礁滩储层地质预测需要深入研究钙藻、海百合等生物的古生态、岩相环境及分布。
关键词:塔里木盆地;塔中玉号坡折带;晚奥陶世;良里塔格组;礁滩相;白云石化

Dolomitization of Upper Ordovician Reef-Shoal Reservoir of Tazhong-ⅡSlop-Break Zone and Dolomitization Contribution to Reservoir

Author's Name: Zheng Xingping, Shou Jianfeng, Zhu Guohua, Shen Anjiang
Institution: HIPG PetroChina
Abstract:
A small amount of dolomitization is found in the Upper Ordovician Lianglitage Reef -Shoal complex reservoir of Tazhong-ⅡSlop-Break Zone in Tarim Basin. The dolomitization commonly are in three fabics: (a)the calcic vadose silt of cave filling, (b)mud matrix of bioclastic packstone, and (c)calcareous alga, eophyton sand and alga-mud sand of grainstone. The result of the dolomitization directly contributes an average 1 percent of the porosity to the reservoir, while the intercrystal pores provide for channels of further erosion, which plays an impor tant role to the formation of an effective reservoir. Biological high-Mg calcite is the important source of magne sium ions for dolomitization. In-depth study on the distribution of Crinoid and Calcareous Alga rock is required to predict this dolomitization-associated reef-shoal reservoir.
Keywords: Late Ordovician; Lianglitage Formation; Reef-Shoal complex; Dolomitization, Pore evolution;Tazhong-ⅡSlop-Break Zone; Tarim Basin
投稿时间: 2008-06-01  
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