Taxonomy term

usgs

Tackling "Boundary Faults" across the Alaska-Yukon border: A report from the field

Our two dusty trucks roll across the airstrip, casting long, late-May shadows down the runway. We spot our colleagues from the Yukon Geological Survey and realize we’ve found the right place after an exhausting 12-hour drive from Anchorage punctuated by several U-turns to find the right unmarked access driveway off the Alaska Highway at the south end of Kluane Lake. The evening air is crisp, and the towering peaks to the south are capped with snow.

15 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

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

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

Mineral Resource of the Month: Kyanite

Kyanite and the related minerals andalusite and sillimanite are anhydrous aluminum silicate polymorphs with the same chemical formula, but with different crystal structures and physical properties. These minerals form during metamorphism of clay-bearing sedimentary rocks or in pegmatites. In the United States, where kyanite is prevalent, these three minerals comprise the kyanite minerals group. It is also known as the “sillimanite group” where sillimanite is more common, particularly in India. The three minerals form under slightly different conditions and rarely occur together. They are composed of about 63 percent alumina and 37 percent silica. When “calcined,” or heated to 1,250 to 1,500 degrees Celsius, they convert to about 88 percent mullite and 12 percent silica (the percentages depend on grain size, impurities present and rate of temperature increase). 

 
13 Aug 2013

Energy Notes: March 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 Jul 2013

Energy Notes: April 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 Jul 2013

Mineral Resource of the Month: Bismuth

Bismuth is a brittle, silvery-white metal with a low melting point and a high density approaching that of lead. Alloys of the metal with lead and tin are known to have been used since the Middle Ages. The metal was referred to as wismuth, and at the end of the 16th century, Georgus Agricola, an early mineralogist, Latinized the Germanic name to bisemutum. 

 
13 Jul 2013

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

Energy Notes: February 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 Jun 2013

Pages