塔河油田奥陶系碳酸盐岩岩溶发育模式的测井分析

构造运动控制着岩溶发育的期次。塔河油田奥陶系主要发育了加里东中期岩溶和海西早期的两期岩溶。加里东中期岩溶保留于本区南部下奥陶统,岩溶较弱,以发育小的溶孔为特征;海西早期的两期岩溶发育于北部下奥陶统,岩溶较强,以大型溶洞、地下暗河为特征。各期岩溶在纵向上可分为三个带：地表岩溶带、垂直渗沈岩溶带和水平潜流岩溶带。利用各岩溶带自然伽玛测井、井径测井、双侧向电阻率、密度测井、中子孔隙度测井、声波副井和地层檄电阻率成傈测井的响应特征,对两口典型井岩溶带进行划分。以“双峰灰岩”为标准,对两口井的岩海带进行横向对比,建立加里东中期和海西早期岩溶空间分布与发育强度的模式。

WELL-LOG ANALYSIS ON KARST MODEL OF ORDOVICIAN CARBONATE IN TAHE OILFIELD

Tectonic movement controls karst sequence and periods. The ka rs ts formed during middle Caledonian and early Hercynian were mainly developed in Ordovician of Tahe oilfield. The karst of middle Caledonian is weak and reserve d in the south sub-Ordovician of Tahe oilfield, characterized by pores. The two karst stages of early Hercynianare strong and reserved in the north sub -Ordovician of Tahe oilfield, characterized by big underground solution cavity and river. Karst system of each stage can be divided into three vertical sectio ns: surface karst layer, vertical infiltration karst layer and horizontal underg round solution underflow karst layer. By means of gamma ray log, caliper log, du al lateral log, compensation density log, compensation neutron log, sonic log an d formation micro resistivity image, Ordovician karst sections in two typical we lls are divided. According to "double-peak carbonate", the karst sections in two typical wells are compared and karst spacial distribution and development mo del of Ordovician carbonate in Tahe oilfield is built.