Abstract:
Using a series of analytic techniques, including polarized light microscope, scanning electronic microscope, X-ray diffraction, Fluorescence, and paleomagnetism etc.,eight diagenetic facies were recognized in the Chang 6 reservoir in the Panguliang area, and the reason of low permeability and porosity was discussed. The sand body of the Chang 6 oil reservoir is subdivided into eight diagenetic facies: strongly compacted biotite facies, carbonate cemented facies, authigenic chlorite cemented facies, chlorite coat remnant intergranular pore facies, chlorite coat remnant intergranular pore-feldspathic solution facies, kaolinite cemented facies, feldspathic corrosion facies, and laumontite and feldspar solution facies, respectively. Central part of the main sand body-characterized by the latter three facies has good oil-bearing properties, thus favorable for hydrocarbon accumulation.
