EARTH Magazine - geology

Do impacts trigger extinctions? Impact theory still controversial

David B. Williams — Wed, 23 Jun 2010 16:52:50

In 1980, a controversial paper proposed that a giant asteroid had struck Earth at the end of the Cretaceous period, killing the dinosaurs and every other large land vertebrate. Years later, impacts have been proposed as the cause of every other known mass extinction. What impact has Impact Theory had on understanding these events?

Extinction-era coal linked to Chinese cancer epidemic

Mary Caperton Morton — Thu, 14 Jan 2010 17:37:59

The people of Xuan Wei, China, suffer the world's highest incidence of lung cancer among non-smokers. Burning coal from the Permian-Triassic boundary may be to blame.

Crystal Ball EARTH: Policy: A tale of two years

Corina Cerovski-Darriau — Fri, 11 Dec 2009 13:05:28

Energy, climate change mitigation and healthcare reform grabbed most of the U.S. policy headlines in 2009. But a few other policy gems — for example, human spaceflight, renewable energy projects on public lands, mining reform and natural hazards — have started coalescing in Congress. EARTH contributor Corina Cerovski-Darriau outlines some of the less high-profile topics we can expect to see debated in 2010.

Storing CO₂ in fizzy water underground

Nicole Branan — Tue, 10 Nov 2009 16:42:36

Sequestering carbon dioxide in underground aquifers may be one way to remove it from the atmosphere. But, once stored underground, will the greenhouse gas stay put? Evidence suggests that the gas mainly dissolves in the water, not the rock — but that should still keep it secure.

Surviving field school: Better than reality TV

Clay Farris Naff — Tue, 20 Oct 2009 12:27:35

David Harwood’s geology field course for future teachers is not a network reality show — but it does have all the humor, drama, challenges and bleepable moments of “Survivor.” Geology 160 also offers authentic geological history that students see, taste and scrape from under their fingernails.

Chemical clues reveal ancient geography

Erin Wayman — Wed, 07 Oct 2009 15:47:04

Reconstructing the history of supercontinents requires careful detective work. A longstanding challenge for geological sleuths is locating the ancient front, or leading, edge of a drifting continent — the part that is constantly reshaped by new collisions.

Deciphering mass extinctions

Brian Fisher Johnson — Wed, 02 Sep 2009 11:23:12

When it comes to mass extinction events, what seems like a simple tale — for example: dinosaurs die, mammals take over — is much more complicated. But extinctions aren't random, either: Written in the rocks are certain "rules" these events seem to follow.

Re-examining the Burgess Shale

David B. Williams — Mon, 24 Aug 2009 09:58:38

A hundred years after it was discovered, the world’s most famous fossil site still holds surprises.

Giant dunes, not mega-tsunami deposits?

Carolyn Gramling — Wed, 05 Aug 2009 16:17:18

Some scientists say giant, wedge-shaped sandy deposits on the coast of southern Madagascar are evidence of a giant tsunami spawned by an asteroid strike 10,000 years ago. But new research suggests these deposits were formed by winds, not mega-tsunamis.

The long legacy of Peru's "Mine of Death"

Mary Caperton Morton — Wed, 05 Aug 2009 16:01:14

The Inca knew there was something sinister about the cinnabar mine in Huancavelica, Peru. Now scientists have unraveled a story of mercury pollution from the mine extending back 3,500 years.

Travels in Geology: Exploring mountains and eating llama in Northern Argentina

Joshua Zaffos — Mon, 27 Jul 2009 12:03:27

Beyond Buenos Aires: From cactus-covered deserts to cloud forests to the sky-scraping Andes Mountains, northwestern Argentina promises contrasting landscapes, astounding geological formations and natural beauty — and a chance to eat llama.

A tale of two rocks: Moon-like rocks right next door

Paul D. Lowman, Patrick T. Taylor and M. Bruce Milam — Thu, 18 Jun 2009 15:21:53

As lunar exploration gears back up, scientists are still puzzling over a longstanding challenge: How to drill into the tough lunar soil to discover what lies beneath. The solution, however, may be quite close to home.

Redefining Quaternary

Carolyn Gramling — Thu, 04 Jun 2009 15:47:30

A geologic period just got a little older.

Alaska's Mt. Redoubt erupts at last

Carolyn Gramling — Mon, 23 Mar 2009 10:59:22

After months of increased rumbling, the volcano came violently awake late Sunday night.

Rewriting rivers: What it means for river restoration

David B. Williams — Fri, 13 Mar 2009 16:13:56

Water-powered mills were key to early American industry; by 1840, tens of thousands of milldams were altering the waterways of the eastern United States. But those dams, it turns out, didn't change streamflow in quite the way geologists once thought they would — and that means restoring the waterways won't be as straightforward, either.