Diagenetic Fluid and Its Impact on Sandstone Reservoirs in the Southern Boxing Sag, Dongying Depression, Bohai Bay Basin, China

Figure 5

SEM-BSE images of beach-bar sandstones in the Boxing Sag. (a) F1, 3314.6 m: authigenic microquartz (Mq) and a few clay minerals; (b) F1, 3314.6 m: authigenic albite (Ab); (c) G351, 2455 m: the feldspar dissolution is accompanied by the precipitation of illite (yellow arrow); (d) G351, 2455 m: barite (yellow arrow) and pyrite (Py) are filled among particles; (e) F1, 3314.6 m: the leached detrital grain associated with chlorite (yellow arrow), and red spot represents an EDS analyzing point; (f) EDS-tested composition of the barite (BaSO₄).

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