Taxonomy term


Travels in Geology: Cones and craters in Flagstaff, Arizona

Few places in the country exhibit as many types of volcanic features — including jagged lava flows, crumbly cinder cones and the remnants of a towering stratovolcano — in as small an area as northern Arizona’s San Francisco Volcanic Field.
04 Oct 2017

Mystery impact may have kicked off dramatic warming event

About 56 million years ago, the planet warmed rapidly in a mysterious event known as the Paleocene-Eocene Thermal Maximum (PETM). Researchers recently discovered evidence in the rock record from around the same time that points to an extraterrestrial impactor striking Earth, but whether the two events are related is yet to be determined.

06 Feb 2017

Buried lunar craters filled by lava long ago

Craters dot much of the nearside of the moon. And buried beneath this pockmarked landscape, according to the latest findings from NASA’s two Gravity Recovery and Interior Laboratory (GRAIL) spacecraft, are the remnants of even more craters, many of which were covered long ago by lava.

12 Jul 2016

Scarps and craters reveal moon's dynamic side

During their 1972 mission to the moon, Apollo 17 astronauts Eugene Cernan and Harrison Schmitt tried to ascend a steep rise in the lunar rover. The rover could not make it, so the pair drove up the incline in a zigzag pattern. The rise, it was later found, is the lobate scarp of a lunar thrust fault — one of many such features that, thanks to detailed images from NASA’s Lunar Reconnaissance Orbiter (LRO), are now known to occur across the moon’s surface. In a new study, researchers suggest these faults were formed by the same gravitational forces that cause the rise and fall of tides on Earth.

19 Feb 2016

Benchmarks: July 22,1960: Mineral discovery ends Meteor Crater debate

In 1923, Daniel Moreau Barringer stood on the edge of a vast bowl-shaped depression in the Arizona desert, watching a drill rig bore into the floor of the crater. Barringer had spent more than two decades exploring the massive hole, which lies on the Colorado Plateau 65 kilometers east of Flagstaff, Ariz. And although he had sunk dozens of drill holes, collected scores of samples, and carefully mapped the piles of talus that draped its concave walls, Barringer still hadn’t found what he was looking for, and he was getting nervous.
22 Jul 2015

Mars Monthly

As Curiosity and Opportunity rove around Mars, the Mars Reconnaissance Orbiter (MRO), Mars Express and Mars Odyssey orbit above, and scientists on Earth study the Red Planet from afar, new findings are announced almost weekly. Here are a few of the latest updates.

10 Jul 2014

Iowa impact crater confirmed

An airborne geophysical survey mapping mineral resources in the Midwest has confirmed that a 470-million-year-old impact crater nearly five times the size of Barringer (Meteor) Crater in Arizona lies buried several hundred meters beneath the town of Decorah, Iowa.

07 Jul 2013

Santa Fe impact crater discovery: A series of fortunate events

In the ancient pink and orange hills of the Sangre de Cristo Mountains, Thornton “Tim” McElvain, a retired petroleum geologist, leads me over a concrete highway barrier to a towering granite road cut. McElvain steps onto a rock pile and points to a meter-long block of granite, the freshest offering to fall from the rock face. One side of the block tapers roughly to the shape of a cone, with grooves coming together to form a point.

“This is the best shatter cone example I’ve seen here,” McElvain says.

07 Oct 2011