鄂尔多斯南部奥陶系马家沟群马六组白云岩成因

DOLOMITE GENESIS OF ORDOVICIAN SYSTEM IN FORMATION MALIU,SOUTHERN ORDOS BASIN

鄂尔多斯盆地古生界天然气的勘探及开发已经取得了很大的成绩 ,这些油气田的储集层或多或少与碳酸盐岩有着密切的关系。因此 ,碳酸盐岩中储集岩的成岩研究具有很大的现实意义。在对 7条野外露头剖面和 6口探井剖面进行现场观察的基础上 ,对上千块样品进行了系统的野外和室内分析。对鄂尔多斯盆地奥陶系马家沟群碳酸盐岩中最主要的岩石类型之一——白云岩的成因及其对储集性能的影响进行了综合研究。研究结果表明 ,本区白云岩是由多因素多期次形成的 ,白云岩形成过程中经过的成岩期次和顺序的不同排列 。

Peleozoic gas exploration and development have achieved great progress in Ordos Basin.The Paleozoic explorations of deep formations in eastern area and western Tarim Basin are still in the ascendant.Reservoirs in these oil fields have less or more relationship with carbonates,which play a very important role in domestic and potential abroad(Middle East and Central Asian,etc) exploration and development markets.Therefore diagenesis research of carbonate reservoir has a great significance.Based on the field observations of seven field outcrop sections and six exploration wells,we integrally studied the genesis of dolomite and the influence factors for the reservoir properties by using various experimental methods on thousands of samples.Dolomite is one of the most important rock types in Ordovician Carbonates of Majagou Group in Ordos Basin.It is indicated that dolomites are multi factor and multi period genesis.The diagenesis periods and different array of sequence experienced in the formation of dolomite play overwhelming roles in reservoir properties.