Niobrara chalk production, Silo Field, Denver Basin, Wyoming, USA - A wrench-fault fractured reservoir

Silo field, discovered in 1980 and located in the northem part of the Denver basin,<br>Wyoming (Figure 1), produces from the fractured Niobrara Formation (Upper Cretaceous) at<br>depths ranging from 7,600 to 8,500 ft (2,318 to 2,593 m). Cumulative production from 40<br>vertical wells at Silo is in excess of 1.3 million BO.