Tight sandstone mineralogy and property data from the Chang 7-8 Member in the western Zhidan Area

Database includes: "Tight sandstone mineralogy and property data from the Chang 7-8 Member, Zhidan Area" (Word document). This dataset encompasses mineralogical statistics from 27 biotite-rich sandstone samples (including 27 sets of point-counting data and 21 sets of XRD data), grain size measurements of feldspathic-quartzose grains and biotite fragments from 19 samples, the density of biotite laminae and bedding-parallel fractures from 10 samples, and measured porosity and permeability from 23 samples, all obtained from the Yanchang Formation (Members 7-8) in the western Zhidan area. The data are employed to illustrate that within a specific provenance setting where tight sandstones with high biotite content typically exhibit poor reservoir quality, the development of extensive biotite laminae and associated bedding-parallel fractures can nevertheless lead to a significant enhancement in permeability. These data are primarily aimed at facilitating petrographic studies of tight sandstones and investigating the correlation between biotite laminae and bedding-parallel fractures, as well as their collective impact on reservoir properties.