古地理学报2024，Vol.26Issue(2)：279-295,17.DOI:10.7605/gdlxb.2024.02.021
鄂尔多斯盆地马家沟组碳酸盐岩-膏盐岩共生体系沉积微相与沉积模式
Microfacies and depositional model of a carbonate-evaporite symbiotic system of the Majiagou Formation in Ordos Basin
摘要
Abstract
The carbonate-evaporite symbiotic system is a rock symbiotic association formed by chemi-cal depositional differentiation.Microfacies analysis and sedimentary model construction of such a system are conducive to revealing the sedimentary information that have guiding significance for oil and gas explo-ration in evaporatic environments.Based on a large number of borehole data of the Majiagou Formation in Ordos Basin,macro-and microscopic observation of the rocks was carried out to identify sedimentary mi-crofacies,analyze sedimentary sequence,and construct sedimentary model.The results show that there are ten types of sedimentary microfacies(MFT1-MFT10)in the carbonate-evaporite symbiotic system of the Majiagou Formation:halite,gypsum,gypsum-bearing dolomite,laminated dolomite,crystalline do-lomitic grainstone,microcrystalline dolomite,microbial dolomite,bioturbated dolomite,laminated lime-stone,crystalline grainstone.four types of sedimentary sequence are developed in the symbiotic system:(1)upper intertidalto supratidal dolomite-gypsodolomite-argillaceous dolostone;(2)lower intertidal evaporite-algal dolomite-dolomite;(3)subtidal laminated limestone-churned limestone-bioturbation lime-stone;(4)lagoonal laminated evaporite-lumpy evaporite-salt rock.Evaporites of the Majiagou Formation were formed during the shallow basins period and low sea level period,while carbonates were formed during the high sea level period.The giant carbonate-evaporite symbiotic system formed through repeated fluctuations in sea level.关键词
微相/生物扰动云岩/微生物云岩/沉积模式/马家沟组/鄂尔多斯盆地Key words
microfacies/bioturbated dolostone/microbial dolostone/sedimentary model/Majia-gou Formation/Ordos Basin分类
天文与地球科学引用本文复制引用
刘国庆,苏中堂,郝志磊,魏柳斌,任军锋,廖慧鸿,吴浩文..鄂尔多斯盆地马家沟组碳酸盐岩-膏盐岩共生体系沉积微相与沉积模式[J].古地理学报,2024,26(2):279-295,17.基金项目
中国石油长庆油田分公司重大科技专项(编号:ZDZX2021)资助.[Financially supported by the Major Science and Technology Special Project of PetroChina Changqing Oilfield Company(No.ZDZX2021)] （编号:ZDZX2021）
