The main reservoir in the lower Shanxi Formation (Lower Permian) is composed of quartz sandstones in Changbei Block of the Yulin Gas Field in the east Ordos Basin.

• 鄂尔多斯盆地东部榆林气田长北区块主力储集层是下二叠统山西组下段的石英砂岩,将用水平井开发。