Abstract: Huimin depression, which is one of the main oil depressions, is a typical terrestrial downfaulted basin.The Jishan sand bed is a delta that originated from northwest Ningjin Rise at the downfaulted period of Huimin depression.Stretching across Zizhen depression, the central upwarping zone and Tianjia zone of the Linnan depression, it is widely distributed.Its main body stretches from northwest to southeast along Su'an trench, and an enriched oil and gas storage was developed in Linshang region, which has great exploitation potential.The exploration in the area has achieved much success, but the origin and sedimentary faces of the sand bed are still disputed, hence, we give some discussions.