Sedimentary Characteristics of Dolomite from Gaoyuzhuang Formation in Beipiao Area,North China
The Neoproterozoic Gaoyuzhuang dolomite from Beipiao area,western Liaoning Province was syste-matically studied based on outcrop and microscope observations.The whole section is composed of several cyclic shallowing upward units (subsequences),which include subtidal massive dolomite and intertidal thin-bedded dolomite.Three types of microfacies,microspar dolomite,dolomicrite and intraclast dolomite,were identified.Partial recrystallization and silica filling/replacement are associated with each microfacies.The chert bands and nodules,which are commonly distributed along the stratigraphic layers,was probably formed during the syn-depositional stage.Silica filling/replacement may have great contributions to dolomite dissolution and recry-stallization and therefore improve the porosity of the dolomite,potentially leading to the formation of the excellent dolomite reservoir.Therefore,silica filling/replacement during the syn-depositional stage is significant for the development and evolution of dolomite reservoirs.
国家科技期刊平台
NSTL
万方数据
维普
