Taxonomy term

sara e. pratt

What lies below?

Technological advances continue to improve the resolution of our view of Earth’s interior, but disagreement remains over what we’re viewing. In a recent Nature paper titled, “Broad plumes rooted at the base of the Earth’s mantle beneath major hot spots,” Scott French, a computational scientist at the Department of Energy’s National Energy Research Scientific Computing Center at Lawrence Berkeley National Laboratory, and Barbara Romanowicz, a seismologist at the University of California at Berkeley, reported the development of the most detailed model yet of the structure of the mantle.
 
20 Dec 2015

No laughing matter: Ocean nitrous oxide emissions greater than thought

Nitrous oxide is a potent greenhouse gas and, since the banning of chlorofluorocarbons in 1987, it has become the main driver of ozone loss from the stratosphere. Most atmospheric nitrous oxide is emitted from agricultural land and soils, but roughly a third is thought to come from the ocean. However, marine sources and sinks of the gas are not well understood. 
 
27 Nov 2015

Geomedia: Television: 'NOVA: Making North America' Is Flashy, But Fails on Storytelling

A new three-hour-long documentary, “NOVA: Making North America,” airing in November, purports to tell the geological, biological and anthropological story of North America. Unfortunately, it falls short on many counts.

17 Nov 2015

Campi Flegrei makes its own concrete caprock

In the 1980s, Tiziana Vanorio was a teenager living in the Italian port city of Pozzuoli west of Naples when the  Campi Flegrei volcanic complex that underlies the town and its harbor began to stir. Between 1982 and 1984, the caldera swelled more than 2 meters — the most rapid volcanic uplift ever measured anywhere. The rising seafloor shallowed Pozzuoli’s harbor so that ships could no longer enter. The uplift was followed by a magnitude-4 earthquake and thousands of microquakes that prompted the evacuation of 40,000 residents. Thereafter, the seismicity waned and the residents returned home, but geologists were left with a puzzle: How did the caldera withstand such extreme strain and deformation for so long without rupturing? 
 
16 Oct 2015

Kennewick Man related to modern Native Americans

After two decades of controversy surrounding the origins of Kennewick Man — a 9,000-year-old skeleton found on the banks of the Columbia River in Washington state — a genomic analysis has revealed that he was, in fact, related to modern Native Americans. The 1996 discovery of the well-preserved skeleton led to a protracted legal battle among scientists, Native American tribes and the federal government over the disposition of the remains, and sparked a scientific debate about the origins of the first Americans. 
 
11 Oct 2015

Declining U.S. water use a challenge for models

Americans are using less water today than they have at any time since 1970, according to a report by the U.S. Geological Survey (USGS), which has tracked water use since 1950 and issues reports every five years. 
 
27 Sep 2015

Ancient floods degassed Lake Kivu

The deep, cold waters of Lake Kivu — a stratified volcanic lake in the East African Rift Valley on the border of Rwanda and the Democratic Republic of the Congo — hold 300 cubic kilometers of carbon dioxide gas and 60 cubic kilometers of methane, which seep from magmatic sources below the lake. An overturning of the thermally stratified waters could release those deadly gases onto a population of nearly 2 million.
 
16 Sep 2015

North American terranes not so exotic after all

The cordillera of western North America is a patchwork of various landmasses, or terranes, that assembled through collision and accretion to the Laurentian Shield, leaving a complicated tectonic history for geologists to unravel.

 
30 Jan 2015

Asbestos found in Nevada and Arizona: Roadblock and potential health hazard?

The discovery of a previously unknown type of asbestos-forming geologic environment means asbestos may be more widespread than thought. But is it a health hazard?

29 Jan 2015

1912 not an exceptional iceberg year

A new study disputes the notion that an exceptional number of icebergs were floating in the North Atlantic the year the Titanic collided with one at roughly 42 degrees North latitude and quickly sank, killing more than 1,500 people. However, the study also suggests that weather conditions around the time of the sinking likely pushed icebergs farther south than normal for that time of year.

08 Jan 2015

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