Taxonomy term

departments

November 10, 1934: Arizona declares war against California at Parker Dam

From above, tiny green irrigation circles draw a narrow buffer along the 2,300-kilometer course of the Colorado River like the brush strokes of a zoomed-in pointillist painting. These vibrant green dots stand out against the buff and ochre hues of the desert palette, a testament to the river’s life-giving waters. Less obvious are the 6.4 billion cubic meters of water that flow, or are pumped, more than 390 kilometers from the Colorado’s gorge through tunnels and canals, up and down hills, to the agricultural and population centers of Southern California each year, and the additional 3.4 billion cubic meters that gurgle toward Phoenix and central Arizona annually.

10 Nov 2013

Mineral Resource of the Month: Thallium

Thallium, a grayish-white metal similar to tin in appearance, was discovered spectroscopically in 1861. Like lead, it is heavy yet soft, and can be cut easily with a knife. When exposed to air, thallium’s luster quickly tarnishes to a blue-gray color owing to the formation of a film of thallium oxide. Its concentration in Earth’s crust is estimated at 0.7 parts per million; mostly it is found in association with potassium minerals in clays, soils and granites, but in general it is not commercially recoverable from those sources. Manganese nodules, found on the ocean floor, also contain thallium.

04 Nov 2013

Energy Notes: July 2012-2013

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.

04 Nov 2013

Energy Notes: June 2012-2013

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.

 
19 Oct 2013

Down to Earth With: Kirk Johnson

In 1967, at a family picnic in Casper, Wyo., 6-year-old Kirk Johnson stumbled across a fossil that looked to him like an ancient rattlesnake tail (it turned out to be a brachiopod). Not long after, while hiking in his home state of Washington, he accidentally knocked over a piece of shale, fortuitously discovering a fossil leaf. The ensuing epiphany that he had a knack for finding fossil treasures led to what he now calls his “paleo obsession.”

16 Oct 2013

Mineral Resource of the Month: Hafnium

Hafnium is a ductile metal with a brilliant silver luster. It does not exist as a free element in nature; it is always associated with zirconium. Its existence was predicted as early as 1869 by Dmitri Mendeleev, but it wasn’t discovered until 1923 when it was found in the mineral zircon by X-ray spectroscopic analysis. Hafnia is the Latin name for Copenhagen, the city where hafnium was discovered.

 
13 Oct 2013

Benchmarks: Sept. 26, 1912: Birth of Preston Cloud, geologist who deciphered banded iron formations

Banded iron formations (BIFs) represent some of the earliest, and most controversial, evidence that the early Earth was devoid of oxygen. These deposits were recognized for their economic value in the mid-1800s, but it wasn’t until the late 1960s when Preston Cloud focused his intellect on  the origins of (BIFs).

26 Sep 2013

Energy Notes: May 2012-2013

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.

 
19 Sep 2013

Down to Earth With: Tanya Atwater

When Tanya Atwater began graduate school in marine geology in 1967, it was considered unlucky for women to be aboard ships. Undaunted, Atwater signed up to work on the first research cruise to take a close look at a seafloor spreading center. Voyage after voyage, she and her mentors fought for her right to work on oceanographic vessels, and it is fortunate they did. Atwater has since had a remarkable career studying plate tectonics and was instrumental in piecing together the evolution of the San Andreas Fault plate boundary.

16 Sep 2013

Mineral Resource of the Month: Lithium

Lithium, the lightest of all metallic elements, has unique properties that have led to its use in a diverse array of applications. For many years, most lithium was used in the production of ceramics, glass and aluminum. More recently, the market for lithium has shifted toward batteries for consumer electronics and electric vehicles.

 
13 Sep 2013

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