鄂尔多斯盆地西部下古生界风化壳优质储集层发育规律及成因机制: 以桃2区块马家沟组马五<sub>1-4</sub>亚段为例<sup>*</sup>

鄂尔多斯盆地西部下古生界风化壳优质储集层发育规律及成因机制: 以桃2区块马家沟组马五_1-4亚段为例^*

冯强汉¹, 许淑梅^2,^3,⁴, 池鑫琪^2,³, 舒鹏程^2,³, 孔家豪^2,³, 崔慧琪^2,³, 马慧磊^2,³

Development regularity and genetic mechanism of weathering crust reservoirs in the western Ordos Basin: take the sub-members 1-4 of Member 5 of Majiagou Formation in Tao 2 block as an example

Feng Qiang-Han¹, Xu Shu-Mei^2,^3,⁴, Chi Xin-Qi^2,³, Shu Peng-Cheng^2,³, Kong Jia-Hao^2,³, Cui Hui-Qi^2,³, Ma Hui-Lei^2,³

鄂尔多斯盆地桃2区块马五_1-4亚段(含)膏云岩膏模孔的特征及充填情况(Ⅱ) a—桃2井3397.50 m$马五_{3}^{2}$小层,膏云岩中膏模孔被渗滤白云石粉砂、天青石局部充填,残余膏模孔大量保存,蓝色铸体,10×4(-);b—桃53井3381.50 m$马五_{1}^{3}$小层,膏云岩的膏模孔被渗滤白云石粉砂、重晶石半充填,残余孔隙大量保存,蓝色铸体,10×4(-);c—陕50井3490.2 m$马五_{4}^{1}$小层,膏云岩的膏模孔被渗滤白云石粉砂、方解石和萤石充填,见少量残余膏模孔孔隙,茜素红染色,蓝色铸体,有残余孔隙,10×4(-);d—桃35井3402.1 m$马五_{1}^{3}$小层,膏云岩的膏模孔被白云石粉砂、方解石和萤石充填,有残余膏模孔孔隙,茜素红染色,蓝色铸体,10×4(-);e—召88井3327.3 m$马五_{1}^{2}$小层,膏云岩的膏模孔被渗滤白云石粉砂、铁方解石和黄铁矿半充填,见少量残余膏模孔孔隙,茜素红染色,蓝色铸体,10×4(-);f—召88井3327.3 m$马五_{1}^{2}$小层,膏云岩中膏模孔被渗滤白云石粉砂、铁方解石和黄铁矿局部充填,见少量残余膏模孔孔隙,茜素红染色,蓝色铸体,10×4(-);g—桃47井3430.2 m$马五_{1}^{3}$小层,膏云岩中膏模孔被渗滤白云石粉砂、萤石和黄铁矿充填,见残余膏模孔或渗滤白云石粉砂粒间孔孔隙,蓝色铸体,10×4(-);h—桃47井3430 m$马五_{1}^{3}$小层,膏云岩中膏模孔被渗滤白云石粉砂和萤石半充填,残余膏模孔孔隙大量保存,蓝色铸体,10×4(-);j—陕225井3455.3 m$马五_{4}^{1}$小层,膏云岩中膏模孔被渗滤白云石粉砂、铁白云石和萤石等不完全充填,形成残余膏模孔, 白云岩基质中晶间孔少见,岩性致密, 扫描电镜照片