摘要
塔中北斜坡鹰山组大规模发育层间岩溶型储集层,岩溶作用深度贯穿不整合面以下180 m范围内。但是不同区块储集层特征差异大、主控因素认识不清等成为制约鹰山组勘探的瓶颈。通过对层间岩溶概念的重新厘定,详细分析塔中井下岩溶型储集层特征,结合构造演化与海平面变化特征,认为塔中鹰山组层间岩溶形成于加里东中期Ⅱ幕构造运动期,暴露时间相对较短,没有形成完整的岩溶体系,大型洞穴不发育,多为孤立的小型洞穴,储集层类型以孔洞型、裂缝-孔洞型为主;暴露时鹰山组地层倾角较小,岩层面与潜水面接近平行,使岩溶作用局部顺层溶蚀,储集层呈准层状分布,但区域上具有穿层性;3期海平面变化与潜水面相对停滞期使鹰一段—鹰二段共发育5套储集层。通过上述分析及储集层分布模式建立,综合预测了有利勘探区块。
Large-scale interlayer karst reservoirs are well developed in the Yingshan formation in Tazhoug northern slope of Tarim basin, where the depth of karstification reaches 180 m below the unconformity. But the reservoir characteristics are varied in different areas and the main-control factors are unclear, which become the bottleneck of restricting the petroleum exploration of Yingshan formation. This pa- per redefines the concept of interlayer karst and analyzes the characteristics of the karst reservoir in Tazhong area. In combination with the structural evolution and the sea level changes, it is suggested that the system of karst is unperfect and the large-scale caves are undevel- oped, because the interlayer karst of Tazhong Yingshan formation was formed in the Caledonian II episode, with short-term outcrops, small and isolated caves, and dominant vuggy and fracture-vuggy types of reservoir. While the low dip angle of the formation when outcropping, the bedding plane and water table were almost parallel, so there existed local bed-parallel karstification, the reservoirs occurred in quasi laminar distribution and regional diachroneity. The three stages of the sea level changes and relative stagnant phase of water table resulted in 5 sets of reservoirs developed from No.1 to No.2 members of Yingshan formation. By analyzing the key controlling factors of reservoir and developing the reservoir distribution model, the favorable exploration blocks are comprehensively predicted in this paper.
出处
《新疆石油地质》
CAS
CSCD
北大核心
2013年第3期277-281,共5页
Xinjiang Petroleum Geology
基金
国家科技重大专项(2011ZX05004-004)
关键词
塔中北斜坡
鹰山组
碳酸盐岩
岩溶储集层
层间岩溶
潜水面
Tazhong northern slope
Yingshan formation
carbonate rock
karst reservoir
interlayer karst
water table
