Meeting the Volcano

Meeting the Volcano

(Overlooking Kilbourne Hole. Photo: Briana Lionetti)

By Briana Lionetti 

Arriving at the edge of the Potrillo volcanic field for the first time, I was a little bewildered. We were standing on the outskirts of a giant hole with layers of sand and the occasional patch of vegetation.

“Where’s the volcano?” I asked Nikki Whelley, a research and education outreach specialist at NASA’s Goddard Space Flight Center.

“You’re looking at it,” she said.

Like most people, I’d imagined volcanoes as massive, cone-shaped mountains that once (or still) spewed fiery lava. But volcanoes come in different forms, and there’s a lot more to them than meets the eye. Most of the action, in fact, is far underground: The crust of the earth is divided into several plates that move over the mantle. Sometimes these plates crash into each other, an explosive phenomenon called plate tectonics.

“A volcano is just earth tectonics trying to get rid of heat,” said Shawn Wright, a planetary scientist from the Planetary Science Institute in Philadelphia. The materials produced inside the earth can be liquid rock (called magma when it’s underground, lava when it rises above the crust), gas or ash.

We accompanied the RIS4E team on their field work at two volcanoes in the Potrillo field. The first, called Kilbourne Hole, is what geoscientists refer to as a “maar,” the result of an explosion that happens when groundwater meets lava or magma. Jake Bleacher, the NASA planetary geologist leading the RIS4E field work at Potrillo, told me that the maar that formed Kilbourne Hole happened about 24,000 years ago.

The other Potrillo site we visited, called Aden Crater, has been quiet for about 16,000 years. It’s known as a  shield volcano, which is characterized mainly by two kinds of volcanic features: lava vents, which are areas in the crust where gases and lava have come out; and lava flows that have come up to the top of the volcano with a very gentle upward slope.

Regardless of the events that formed them, volcanoes aren’t exactly set in stone. They go through phases that last thousands of years. A volcano is considered active if it has had at least one eruption in the past 10,000 years. If it hasn’t erupted in that long, and isn’t expected to again, a volcano is considered extinct.  If it’s not erupting now but might in the future, it’s classified as dormant.

One of the most active volcanoes in the world is in Iceland. It erupted in 2010, causing 20 countries to close their air space and affecting 100,000 travelers across Europe. Hawaii has an active volcano, Mauna Loa, a shield volcano that is still slowly spewing lava.

Jose Hurtado, a geologist at the University of Texas at El Paso who joined the RIS4E team at Potrillo, explained to us what Kilbourne Hole looked like before, during and after the explosion that created it all those thousands of years ago. The earth was between ice ages, he said, and a lot wetter than it is now. Kilbourne Hole resembled the African Serengeti, with large animals such as wooly mastodons and ground sloths walking around.

“The day of the eruption would’ve been quite a bad day for these poor creatures that were out on the west Texas and southern New Mexico savanna,” Hurtado said. The ash that exploded from inner earth may have gone as high as 50,000 feet, eventually collapsing in successive pulses. In the following days the volcano would probably have had steam coming out of the ash deposits and maybe “a few burps every now and then.”

“It would’ve been quite a scene,” Hurtado said.

(Overlooking Kilbourne Hole. Photo: Briana Lionetti)

By Briana Lionetti 

Arriving at the edge of the Potrillo volcanic field for the first time, I was a little bewildered. We were standing on the outskirts of a giant hole with layers of sand and the occasional patch of vegetation.

“Where’s the volcano?” I asked Nikki Whelley, a research and education outreach specialist at NASA’s Goddard Space Flight Center.

“You’re looking at it,” she said.

Like most people, I’d imagined volcanoes as massive, cone-shaped mountains that once (or still) spewed fiery lava. But volcanoes come in different forms, and there’s a lot more to them than meets the eye. Most of the action, in fact, is far underground: The crust of the earth is divided into several plates that move over the mantle. Sometimes these plates crash into each other, an explosive phenomenon called plate tectonics.

“A volcano is just earth tectonics trying to get rid of heat,” said Shawn Wright, a planetary scientist from the Planetary Science Institute in Philadelphia. The materials produced inside the earth can be liquid rock (called magma when it’s underground, lava when it rises above the crust), gas or ash.

We accompanied the RIS4E team on their field work at two volcanoes in the Potrillo field. The first, called Kilbourne Hole, is what geoscientists refer to as a “maar,” the result of an explosion that happens when groundwater meets lava or magma. Jake Bleacher, the NASA planetary geologist leading the RIS4E field work at Potrillo, told me that the maar that formed Kilbourne Hole happened about 24,000 years ago.

The other Potrillo site we visited, called Aden Crater, has been quiet for about 16,000 years. It’s known as a  shield volcano, which is characterized mainly by two kinds of volcanic features: lava vents, which are areas in the crust where gases and lava have come out; and lava flows that have come up to the top of the volcano with a very gentle upward slope.

Regardless of the events that formed them, volcanoes aren’t exactly set in stone. They go through phases that last thousands of years. A volcano is considered active if it has had at least one eruption in the past 10,000 years. If it hasn’t erupted in that long, and isn’t expected to again, a volcano is considered extinct.  If it’s not erupting now but might in the future, it’s classified as dormant.

One of the most active volcanoes in the world is in Iceland. It erupted in 2010, causing 20 countries to close their air space and affecting 100,000 travelers across Europe. Hawaii has an active volcano, Mauna Loa, a shield volcano that is still slowly spewing lava.

Jose Hurtado, a geologist at the University of Texas at El Paso who joined the RIS4E team at Potrillo, explained to us what Kilbourne Hole looked like before, during and after the explosion that created it all those thousands of years ago. The earth was between ice ages, he said, and a lot wetter than it is now. Kilbourne Hole resembled the African Serengeti, with large animals such as wooly mastodons and ground sloths walking around.

“The day of the eruption would’ve been quite a bad day for these poor creatures that were out on the west Texas and southern New Mexico savanna,” Hurtado said. The ash that exploded from inner earth may have gone as high as 50,000 feet, eventually collapsing in successive pulses. In the following days the volcano would probably have had steam coming out of the ash deposits and maybe “a few burps every now and then.”

“It would’ve been quite a scene,” Hurtado said.