Dissolution Characteristic of Feldspar in Chang-8 Reservoir, DZ and ZY Region, Xifeng Oilfield of Ordos Basin

Feldspar dissolution phenomenon in Xifeng Oilfield DZ, ZY common areas, feldspar and secondary porosity generated by dissolution study area is an important reservoir of oil and gas reservoir space. This study in order to clarify the situation and development of secondary porosity in the study area, the comprehensive utilization of rock thin section, scanning electron microscopy, X-ray diffraction analysis of the region's 33 wells 150 rock samples of feldspar dissolution features fine description. Studies show: feldspar dissolution porosity reservoir space, the contribution rate of up to 60%, and feldspar dissolution phenomenon common development in the study area, according to the shape and structure feldspar dissolved pore and feldspar grains can be divided along the periphery of partial dissolution intragranular holes along feldspar twin planes or cleavage seam penetration, dissolving the formed strip, etc., and honeycomb pore structure comprising two or more single; Harbour shape formed by the edge of the arc-shaped tablets dissolved pores the compound dissolved pores..