Reseach on the sandstone diagenesis of the 8th member of Shihezi Formation in north of Zichang area

Multiple analysis methods including general slice and casting slice scan electron microscope,etc,were adopted to study the diagenesis of the 8th member of Shihezi Formation sandstone of the study area and its effects on physical properties.The result shows that Lithic quartz sandstone is the main sandstone type,with less or low composition feldspar;compaction is one of the main causes for porosity losses,and the primary porosity loses further under cementation which is also the main cause of this compact sandstone,especially,carbonate,secondly,quartz increasing margin and kaolinite,but cementation of chlorite film can restrain compaction and is beneficial to preserve primary porosity.Physical properties of sandstone reservoirs can be improved by dissolution,during the later period of diagenesis.Diagenesis reaches A-B period,porosity developed by dissolution is one of the main porosity-type of this period,where it is developed well is the favorable reservoirs area.