岩溶改造古地貌恢复在油气矿产勘查中应用

Karstification Paleogeomorphology restoration application in prospecting for oil and gas

在塔河油田2区区域地质背景分析的基础上,结合奥陶系地层发育、沉积环境及构造演化研究,查明了该区奥陶系岩溶改造的根本原因,应用岩石薄片、阴极发光、碳酸盐岩矿物同位素分析技术手段,得出该区奥陶系岩石薄片溶孔壁存在氧化特征及陆源碎屑;填积物阴极发光为桔红色等指示强氧化形成条件;碳酸盐岩矿物同位素指示大气水介质作用;综合分析得出海西早期奥陶系岩溶环境为开放系统的陆壳大气水渗滤到地层形成的岩溶改造环境。应用地震单井资料恢复了该区奥陶系顶界面的岩溶古地貌,结合岩溶地形特征,认为该区洼凼北部岩溶缓坡附近泄水改造区域为油气矿产资源聚集最有利区域。

Based on the analysis of geological background of 2area of Tahe oil field,and combined with the development of Ordovician strata,studyed on the sedimentary environment and tectonic evolution,finded out the fundamental reason for the transformation of the Ordovician karst,application of rock thin sections,cathodoluminescence,carbonate mineral isotope analysis technology,it is concluded that the Ordovician rock slices dissolved pore wall existed the oxidation characteristics and terrigenous clastic;the fill material cathode luminous orange red etc that indicated the formation conditions of the strong oxidation;the carbonate mineral isotope indicated the atmospheric water medium;the comprehensive analysis showed that the Hercynian Early Ordovician karst environment is an open system of the continental crust of atmospheric water infiltration to the formation of karst environment transformation.Application of seismic data of single well restored the Ordovician top interface of karst landform,combined with karst terrain features,it concluded that the region near the region of northern karst slope was draining wa Dang transformation which was the most favorable area for oil and gas accumulation of mineral resources.