[Retracted] Effectiveness of Oil Filling in Tight Sandstone Reservoirs of Yancheng Formation in Ordos Basin

Table 1

Description of 7 segments of the Yancheng Formation.

Characteristic	Lithology description	Thickness (m)
Yancheng group 71	Thick fine sandstone and siltstone mixed with argillaceous siltstone and mudstone	35∼45 m
Yancheng group 72	Thick fine sandstone, thin siltstone interbedded with mudstone, and thick mudstone and muddy siltstone.	25∼35 m
Yancheng group 73	Black oil shale and occasionally thin tuff deposits.	35∼45 m