Taxonomy term

november 2015

Mineral Resource of the Month: Pumice and Pumicite

Pumice is an extrusive igneous volcanic rock formed through the rapid cooling of air-pocketed lava, which results in a low-density, high-porosity rock. Fine-grained pumice, or pumicite, is defined as minute grains, flakes, threads or shards of volcanic glass, with a size finer than 4 millimeters. 

30 Oct 2015

Energy Notes: April 2014-2015

Oil and petroleum imports data are preliminary numbers taken from the American Petroleum Institute’s Monthly Statistical Report. For more information visit www.api.org.

30 Oct 2015

Down to Earth With: Geophysicist Julian Lozos

Julian Lozos, a postdoctoral researcher affiliated with both the U.S. Geological Survey and Stanford University, designs computer models that simulate earthquakes. As a graduate student at the University of California at Riverside (UC Riverside), Lozos discovered part of what makes the San Jacinto Fault — a major fault in Southern California underlying the homes of millions — tick. For this work, Lozos received the Outstanding Student Presentation award at the annual meeting of the Seismological Society of America three years in a row, an unprecedented accomplishment.
 
29 Oct 2015

Geomedia: Film: Banff Mountain Film Festival is geologic showcase

The Banff Mountain Film Festival World Tour is a traveling collection of outdoor adventure films that feature the stories of climbers, alpine skiers, mountain bikers and other mountaineers, which are often set against geologically astounding backdrops. 
 
27 Oct 2015

Owl pellets bridge ancient and modern ecosystems

In Homestead Cave near Utah’s Great Salt Lake, owls have been regurgitating pellets containing the undigested bones and hair of prey — typically small mammals like rodents — at a relatively constant rate since the end of the Pleistocene glaciations about 13,000 years ago. Those pellets have stacked up and fossilized in the cave to present a near-continuous glimpse into how mammal communities in this part of the Great Basin region have changed over time. Now, paleontologists examining bones in the pellets have found that, although small mammals in the region have generally been able to adapt to shifting ecosystems in the past, today, in the face of landscape-altering human activity, the mammal population is changing in unprecedented ways.
25 Oct 2015

Triceratops relative 'Wendi' sported a fantastic frill

The discovery of a 79-million-year-old frilled and horned relative of Triceratops is shedding light on the early evolution of the ceratopsid’s distinctive look. The new specimen, discovered in a quarry in southern Alberta, Canada, and described recently in PLOS ONE, was named Wendiceratops pinhornensis after the famed fossil hunter Wendy Sloboda of the University of Lethbridge in Alberta, who discovered the site in 2010.
 
24 Oct 2015

Santa Ana winds get a fiery boost from the stratosphere

Southern California’s Santa Ana winds have long been implicated in the region’s dangerous and destructive wildfires. Now, a new study in Geophysical Research Letters points the finger at an accomplice: a phenomenon called stratospheric intrusions, which are natural atmospheric events that bring warm, dry air from the upper atmosphere down to the surface. These intrusions may exacerbate fires, as well as the region’s infamously bad air pollution.
 
23 Oct 2015

Rosetta spies cometary sinkholes

Large circular pits seen on comet 67P/Churyumov-Gerasimenko by the European Space Agency’s Rosetta spacecraft may be sinkholes rather than craters left by explosive eruptions or impacts, according to scientists who analyzed images taken by Rosetta’s OSIRIS camera.
 
22 Oct 2015

Tree of life reshaped

Since the 1970s, the classic “tree of life” taught in classrooms has portrayed three domains of life — Archaea, Bacteria and Eukaryota — all descending from an unknown common ancestor. But behind the scenes, this textbook picture has been shifting. Many scientists now think the tree’s deepest root lies within the bacteria; and, even more recently, some have begun suspecting that the Eukaryota — including all animals, plants, fungi, slime molds and other organisms whose cells have nuclei — are actually an offshoot from the Archaea, paring the tree from three to two domains. Now, a new study furthers that claim, and with the help of a novel technique for parsing phylogenetic data in greater detail than ever before, suggests a revised backstory for the Archaea — and, by extension, us.
 
21 Oct 2015

A Cambrian-like explosion of mammals in the Mid-Jurassic

Dinosaurs dominated the continents during the Mesozoic, and for a long time, paleontologists assumed our mammalian ancestors kept a low-profile in that era, existing only as small, ground-dwelling, nocturnal insect-eaters. But in the last decade, discoveries of an ever-increasing diversity of mammal fossils have forced a rethink: Mesozoic mammals were also gliders, climbers, diggers and swimmers. Now, scientists looking at mammalian rates of evolution during the time of the dinosaurs have found that this diversity peaked in the Mid-Jurassic, leading to new physical characteristics that would remain for millions of years.
 
20 Oct 2015

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