This work carried
out a high-resolution and systematic core sampling
of well Z101 in the YQ city, southern Ordos Basin, and the well location
is shown in Figure 1. The lithology of the samples is gray and black, black mud shale,
black oil sandstone, gray and dark gray mud siltstone, and gray and
dark gray silt mudstone (Figure 1). The samples range from Chang 3 to 8 members of the
Yanchang Formation. Representative samples were selected for organic
and inorganic geochemical analyses. The tests included total organic
matter content, organic carbon and kerogen stable carbon isotopes,
aliphatic and aromatic hydrocarbons, gas chromatography–mass
spectrometry, stable carbon isotopic compositions of individual hydrocarbons,
and major/trace elements.