Monthly Archives: April 2015

Geologic map reveals US basement rock origins

By combining data about surface mineral resources, national-scale gravity and aeromagnetic surveys, and the age and origins of basement rocks, the USGS has developed a map of the basement rocks underlying the United States. Basement rocks sit above the mantle but beneath all other rocks and sediments. The full report is available here. Read more

Yellowstone magma: a new chamber, bigger and deeper

Will the Yellowstone magma chamber--make that chambers--ever stop growing? Well, they're not actually growing per se; rather, scientists are discovering that Yellowstone's magma chambers are bigger--and more numerous--than previously believed. In 2013, the upper magma chamber was revealed to be more than double its previously estimated volume. Then, this month, geophysicists announced the existence of an additional, deeper, larger magma reservoir sitting between the upper chamber and the mantle plume feeding the legendary volcano. Check out the video below, by the University of Utah, to see a 3D animation of the setup. You can read more about Yellowstone eruptions in my previous post, which has been updated. Read more

The Neanderthal in the karst: hapless skeleton dated at 150,000 years old

During the age of the mammoth, a hominin roaming southern Italy stumbled into a hole in the karst landscape. Out of reach of sun and predator, he starved to death, his body decaying and his bones slumping into a pile, mineral-rich waters ultimately calcifying and fusing them into the surrounding limestone. Locked in the limestone, his skeleton would remain there until 1993, when cave explorers found his face--upside down--staring back at them. Read more