Sand Body Description for Upper Sangonghe Formation (Early Jurassic), Baolang Oilfield, Yanqi Basin Northwest China

The Yanqi Basin is located NW of China, Sangonghe formation (Early Jurassic) consists mainly channels, characterized by a complex geological. The first type channel has small size and appeared in the ‘well log’ as bell shaped ,second type which is thin and wide appeared in the well log as box-shaped and reflects the water high energy and strong and continuous erosion .The third type of these channels is thick with coarse deposits .These channels isolated, locally connected and connected on a wide scale .The types sand body slightly curved, laterally connected and isolated. The thickness less than 10m ,the lateral extension 320m to 1650m.The second Sand body layer is slightly curved broadband-like with thickness of 10 ~ 20m ,lateral extension between 1500m to 2050m.The third type thickness is more than 20 m , lateral extension more 4000m.The interlayer represented: 80%, 50%-80%, 30%-50% and less than 30 %.