Volcanism in the Markagunt volcanic field occurred in three stages. The first stage saw activity mainly at the margins of the Markagunt Plateau between 5.3 and 2.8 million years ago; the cinder cones and lava flows produced during this stage are heavily eroded. The second stage occurred along the Sevier fault and in the southern part of the field between 800,000 and 500,000 years ago; its cones and lava flows are moderately eroded. The third group was emplaced during the middle Pleistocene and Holocene.