Wellsville Mountain forms the extreme northern end of the Wasatch Range in northern Utah. It lies at the western margin of the Middle Rocky Mountain province and is bordered by valleys of the Basin and Range province. Many geologic investigations have been made in this region. Much of the Wasatch Range has been studied and mapped as well as parts of the Bear River Range, east of Cache Valley, and the Malad Range which extends north from Wellsville Mountain; however, the geology of Wellsville Mountain has not been studied or mapped in detail. Some reconnaissance mapping has been done and sections of Cambrian and Pennsylvanian formations have been measured on the western mountain front (Maxey, 1941; Williams, 1943), but little is known about the middle Paleozoic formations and the structural geology of the northern part of the mountain.