The geology as one transitions off the Colorado Plateau to the west towards the Basin and Range can seem a jumbled mess. Join geologist Ben Everitt as he sheds light on this jumble and we explore what is potentially the world’s largest laccolith (a floored igneous intrusion), the Pine Valley Mountains. The class will begin and end in the town of Leeds. Although the heart of the mountain is inaccessible without some strenuous hiking, we will tour the south flank, where the floor of the laccolith is exposed, resting on the pink limestone of the Claron Formation. There will be some short walks to look for dinosaur tracks in the sedimentary layers, and to inspect the varieties of igneous rocks. The trip will end with a visit to the Silver Reef Museum in Leeds, which describes the brief silver mining boom of 1875-1885. Limited to 12 participants.