The Evolution of Diagenetic Fluids and Accumulation Characteristics of Tight Sandstone Reservoir in Upper Paleozoic, Southwestern Ordos Basin

Figure 6

Microscopic characteristics of fluid inclusions in the sandstone reservoir of the study area. (a) Gas-liquid two-phase inclusions in dissolution pores, He 3 well, Shan 1 section, 4146.16 m; (b) oriented gas-liquid two-phase inclusions in fissures in early stage, Lian 1 well, Shan 1 section, 3467.72 m; (c) gas-liquid two-phase inclusions in dissolution pores, Lian 1 well, Shan 1 section, 3424.26 m; (d) oriented gas-liquid two-phase inclusions in fissures in early stage, Qingshen 2 well, Shan 1 section, 4732.6 m; (e) dark-colored hydrocarbon gas-liquid two-phase inclusions in the dissolution pores, He 3 well, Shan 1 section, 4146.62 m; (f) same view field of (e) under the fluorescence microscope; (g) dark hydrocarbon gas-liquid two-phase inclusions in early fissures, Lian 1 well, Shan 1 section, 3424.26 m; (h) same view field of G under the fluorescence microscope; (i) gas-liquid two-phase inclusions along late fissues, He 3 well, He 8 section, 4081.68 m; (j) gas-liquid two-phase inclusions with beaded fractures and directional distribution, Qingshen 2 well, Shan 1 section, 4722.8 m; (k) late dark gas-rich inclusions, Lian 1 well, Shan 1 section, 3424.26 m; (l) gas-rich inclusions with fracture distribution in late stage, Qingshen 2 well, 4730.14 m.

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