Provenance analysis and reservoirs characteristics of the clastic rocks from the Yangchang Formation in west-central Ordos Basin

The provenance analysis of the clastic rocks from the Chang-6 oil reservoirs in the west-central Ordos Basin is based on sandstone composition,cathodoluminescence,heavy mineral assemblages and palaeocurrents.The types of parent rocks include metamorphic rocks,acidic magmatic rocks and carbonate rocks.The sediments are derived primarily from the northeastern and southwestern parts,and secondly from the northwestern,western and southern parts of the basin.These provenances may have exerted an important effect on the types,compositions of interstitial materials and physical properties of sandstone reservoirs.