Fluid interaction mechanism and diagenetic reformation of basement reservoirs in Beier Sag, Hailar Basin, China

LI Juan,WEI Pingsheng,SHI Lanting,CHEN Guangpo,PENG Wei,SUN Songling,ZHANG Bin,XIE Mingxian,HONG Liang

Fig. 2. Spatial characteristics of basement reservoir in Beier Sag of Hailar Basin. (a) Well B15, 2225.70 m, epimetamorphic fine sandstone, with unfilled high-angle fracture, core picture; (b) Well B16b2, 1857.05 m, altered sandstone, with dissolution pores, core picture; (c) Well B40, 2367.30 m, andesitic tuff, with dissolved fractures and pores, fractures are filled by calcite, quartz and pyrite, core picture; (d) Well B15, 2207.00 m , altered inequigranular sandstone, with feldspar particles dissolved, SEM; (e) Well X4, 2897.85 m, andesitic tuff, with dissolved dolomite pore, cast thin section; (f) Well X4, 2893.84 m, andesitic tuff, tuffaceous dissolved pores, cast thin section; (g) Well X4, 2897.85 m, andesitic tuff, with residual intergranular pores, cast thin section; (h) Well B40, 2372.47 m, andesitic tuff, with intergranular micro-pores in authigenic clay mineral smectite, SEM; (i) Well B40, 2361.30 m, andesitic tuff, with irregular fractures, intergranular and intragranular dissolution pores, forming interconnected fracture-pore reservoir space, Laser confocal microscope.