Introduction
Volcanic fields are clusters of volcanoes or areas covered by volcanic rocks. Monogenetic volcanic fields consist mostly (or exclusively) of monogenetic volcanoes. These volcanoes (cinder cones, maars, tuff rings, and eruptive fissures) each experience one period of activity.
Most monogenetic volcanic fields include areas covered by basaltic lava flows and clusters of cinders cones and/or maars and tuff rings, sometimes with a composite volcano or shield volcano located near the center of the field.
Monogenetic volcanic fields form in areas with low magma supply. Individual volcanoes in these fields do not share a common volcanic plumbing system. Each subsequent batch of magma from the source region forms its owns conduit system to reach the surface. Monogenetic volcanic fields can consist of as many as hundreds of individual volcanoes, with long periods of time between eruptive episodes.
National Park Monogenetic Volcanic Fields
At least 13 units of the National Park system contain all or parts of monogenetic volcanic fields.
Bering Land Bridge National Preserve
Bering Land Bridge NPres contains two monogenetic volcanic fields.
The Espenberg Volcanic Field is the northernmost volcanic field in North America, lying above the Arctic Circle. The field consists of five maar volcanoes and five small shield volcanoes.
The Imuruk Lake Volcanic Field consists of approximately 75 vents and associated basaltic to andesitic lava flows. The field contains small shield volcanoes and cinder cones. The most recent eruption produced the Lost Jim lava flow between 1,000 and 2,000 years ago.
Source: U.S. Department of the Interior, National Park Service
