塔里木盆地玉北地区奥陶系鹰山组储层特征及岩溶模式

通过岩心观察、孔洞缝统计、测井、成岩演化等综合研究,指出玉北地区不同构造带之间奥陶系鹰山组风化壳储集空间类型及其性能存在较大差异,其中玉北NE向构造带鹰山组风化壳叠加多期岩溶,发育洞穴、孔洞、裂缝等多种储集空间,储集性能较好;平台区、玉东断洼区仅发育加里东中期Ⅰ幕岩溶,储集性能较差且多以裂缝+弱溶蚀孔为主;而鹰山组下部岩溶内幕在白云岩化作用下,发育大量顺层状溶蚀孔洞和裂缝性储层,但孔洞呈孤立状,连通性较差,未—半充填(油或方解石)。建立了该地区鹰山组岩溶储层发育模式,指出加里东中晚期—海西早期构造运动是控制古地貌、影响岩溶储层发育的主要原因。

Reservoir characteristics and karst model of Ordovician Yingshan Formation in Yubei area,Tarim Basin

By means of core observation, statistics of pore, hole and fraction, logging, and diagenesis, researches are carried out, indicating that the reservoir space types and property of the weathering crust of the Ying-shan Formation are different among different structures in the Yubei area. The superposition of multi-period karst took place in the weathering crust of the north-east trending structure in the Yubei area, and the reservoir spaces such as cave, hole and fracture developed, showing good reservoir property. In the Pingtai area and the Yudong fault depression, only the middle Caledonian stage Ⅰ karsts generated with poorer reservoir property, mainly of fractures and weak solution pores. Because of dolomitization, bedding solution pore and fracture reservoirs deve-loped in karst insider of the lower member of the Yingshan Formation, and pores and holes occurred alone, showing poor connectivity and no/half filling (oil or calcite). The evolution models of the Yingshan Formation karst reservoirs were established. And the tectonic movement of the middle-late Caledonian and early Hercynian controlled ancient landform and influenced the karst reservoir development in the Yabei area.