Black Rock Desert volcanic field Black Rock Desert volcanic field The Black Rock Desert volcanic field in Millard County, Utah, is a cluster of several volcanic features of the Great Basin such as Pavant Butte and Tabernacle Hill. The field's Ice Springs event was an explosive eruption followed by lava flows that were Utah's most recent volcanic activity (1140–1440 AD). which overlapped the older flows of Pavant Butte. The Pleistocene-Holocene field has been an active tectonic area for approximately 2.7 million years. Within the past 1.5 million years, local volcanism has produced both rhyolitic and basaltic cones from near twenty-four vents from which lava escapes
Cinder Cone and the Fantastic Lava Beds and the two Fantastic Lava Beds flows. The second Fantastic Lava Beds flow that all scientists but Diller thought had been erupted in 1851. At the Old Bench and Painted Dunes lava flows, the volcanic ash is brightly oxidized because it interacted with the lava flows when they were still hot. It shares its compositional group with the Fantastic Lava Beds flows, which represent the last flows erupted at Cinder Cone. Ultimately, the eruptive sequence at Cinder Cone took place over the course of several months. An unusual characteristic of the Fantastic Lava Beds is the presence of anomalous quartz