Dotsero Crater

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Dotsero is a 700 meter wide by 400 meter deep maar volcano (broad, low relief crater). Erupting approximately 4200 years ago, it is the youngest volcano in Colorado. It is currently dormant.

This Holocene volcano erupted in the year 2220 BCE, give or take 300 years. When Dotsero blew, it created small scoria cones that were constructed along a NNE-SSW line on either side of the maar. The eruption date is based upon radiocarbon dating of wood found underneath some of the scoria.

It is one of the youngest eruptions in the continental U.S. and it produced an explosion crater, a lahar, and a 3-kilometer (1.9 mi) long lava flow.

Interstate 70 cuts across the lava flow.