Pore Fluid Evolution Influenced by Volcanic Activities and Related Diagenetic Processes in a Rift Basin: Evidence from the Paleogene Medium-Deep Reservoirs of Huanghekou Sag, Bohai Bay Basin, China

Figure 5

Photomicrographs of zeolite diagenesis and dissolved zeolite related to basalt eruption of the Paleogene sandstone reservoirs in well BZ-1. (a) Zeolite precipitated perpendicular to basalt rock fragments, E₃d₁, 2259 m (7411 ft). (b) Zeolite filled in intergranular pores, E₃d₁, 2265 m (7431 ft). (c) Zeolite developed pervasively and chlorite clay envelope occurred, E₃d, 2351 m (7713 ft). (d) Micrograph of thin section showing the zeolite partly and completely dissolved and chlorite clay envelope occurred, E₃d₁, 2280 m (7480 ft). (e) Micrograph of thin section showing dissolved amygdaloid pores of zeolite, E₃d₁, 2280 m (7480 ft). (f) Micrograph of thin section showing the zeolite partly and completely dissolved, E₃d₁, 2280 m (7480 ft). BR = basalt rock fragments, CCE = chlorite clay envelope, Kf = K-feldspar, Q = quartz, Zeo = zeolite, and ZDP = zeolite dissolved pore.

(a)

(b)

(c)

(d)

(e)

(f)