WINTER 2021
New Mexico’s Volcanic Hazards: A Matter of Time ew Mexico’s world-renowned land- one side of the fault moves upward, forming (known as calderas to volcanologists, because Nscapes reflect the vigorous geologic mountains, while the other side of the fault of their resemblance to large caldrons) activity of the region. For those who live moves downward, producing a basin. The erupted in southwestern New Mexico, each here, we see—and sometimes even feel—this Sandia Mountains and the Albuquerque of which injected dozens to hundreds of Earth energy. However, such geologic vigor basin are a textbook example of this process. cubic miles of ash into the atmosphere, and comes with a price in the form of geologic Recent volcanism in New Mexico can be spilled hot, incandescent ash-flows across hazards. Reports on the evening news about divided into two broad periods of activ- the landscape. Before and after the colossal earthquakes in eastern New Mexico are ity, each with their own distinctive traits. supereruptions, numerous “small” volcanoes increasingly common. Driving over moun- Between about 37 and 25 million years ago, erupted, producing explosions similar to tain passes and through deep gorges of a cluster of about twenty supervolcanoes the famous May 18, 1980 eruption of Mt. northern New Mexico may require dodging boulders on the road—evidence of recent Maps and photographs A) Basaltic lava flows, rock falls and landslides. Floods from the showing the two different B such as the 5,200-year-old summer monsoons frequently reshape our styles of recent eruptions flow near Carrizozo (the neighborhood arroyos, and redesign in New Mexico. second youngest eruption in New Mexico), are the rapids in our rivers. One of the A greatest potential hazards in New Mex- 380 common. The lava flowed 45 miles south down the Mexico, one not experienced by Tularosa Basin. B) Young any humans in recent history, is a flows, such as in Valley of volcanic eruption from the many Carizzozo Fires State Park, typically young volcanic fields found in the have very little vegetation state. In this article, we explore and a well-preserved 54 the history of young volcanoes in flow surface. New Mexico, describe recent n