千米桥潜山奥陶系碳酸盐岩储层成岩作用与孔隙演化

Diagenesis and pore evolution of Ordovician carbonate reservoirs in Qianmiqiao buried hill

渤海湾盆地千米桥潜山奥陶系储层经历了两次裸露岩溶及古近纪后的深埋藏成岩作用。其中 ,印支 -早燕山期裸露岩溶属溶丘 (梁 ) -洼地型岩溶发育模式 ,是储集空间形成的重要时期。 6期胶结事件的详细解剖表明 ,喜马拉雅期深埋藏岩溶主要与腐蚀性热流体的作用有关 ,是形成现今储层孔隙系统的最关键时期。局限的热液岩溶和裸露的背斜轴部之下地表岩溶的混合带 ,对千米桥潜山奥陶系孔隙分布具有重要控制作用。印支期挤压逆冲形成的背斜轴部 ,特别是潜山内幕背斜形态与潜山顶面形态相互协调的区域 ,是储层发育最好的部位。

Ordovician carbonate reservoirs in Qianmiqiao buried hill have experienced two periods of bare karst and post-Paleogene deep buried diagenesis. The bare karst during Indosinian-early Yanshan epoch, an important period for the formation of reservoir spaces, belongs to karst development mode of haystack hill-hollow type. Detailed study of 6 cementation events shows that deep-buried karst in Himalayan period, a critical period for the development of current reservoir pore system, is related to corrosive thermal fluids. The zones characterized by both local thermal fluid karst and surface karst under the outcropped anticlinal axes control the distribution of pores in Ordovician reservoirs in Qianmiqiao buried hill. Reservoirs are best developed in the anticlinal axes formed by compressional thrusting during the Indosinian epoch, especially in the areas where the shapes of anticlines within the buried hill harmonize with that of top of buried hill.