Earth and Planetary Sciences Content

Tiny Earthquakes Reveal Hidden Faults Under Northern California

Andy Fell — January 15, 2026 - 11:54am

By tracking swarms of very small earthquakes, seismologists are getting a new picture of the complex region where the San Andreas fault meets the Cascadia subduction zone, an area that could give rise to devastating major earthquakes. The work, by researchers at the U.S. Geological Survey, the University of California, Davis, and the University of Colorado Boulder, is published Jan. 15 in Science.

The Carbon Dioxide Climate Debt

Katherine E Kerlin — December 04, 2025 - 2:26pm

�鶹��ý experts describe the human barriers and opportunities for meaningful action to reduce global emissions and the world's staggering climate debt.

Looking Inside Icy Moons

Andy Fell — November 24, 2025 - 10:43am

The outer planets of the Solar System are swarmed by ice-wrapped moons. Some of these, such as Saturn’s moon Enceladus, are known to have oceans of liquid water between the ice shell and the rocky core and could be the best places in our solar system to look for extraterrestrial life. A new study published Nov. 24 in Nature Astronomy sheds light on what could be going on beneath the surface of these worlds and provides insights into how their diverse geologic features may have formed.

How Earth’s Greatest Extinction Really Happened

Andy Fell — November 21, 2025 - 1:18pm

Around 252 million years ago, the Earth experienced its largest mass extinction. Known as the “Great Dying,” this cataclysmic event wiped out more than 81% of marine species and 70% of life on land.

Deep-Water Sediments Reveal Patterns of Extraterrestrial Influence on Earth’s Ancient Climate

Andy Fell — October 31, 2025 - 10:42am

Roughly 34 million years ago, the Earth started transitioning from a greenhouse to an icehouse state — defined by long-term cooling trends that resulted in ice sheets in the planet’s polar regions. During this time, continental carbon reservoirs expanded as carbon dioxide decreased in the atmosphere.

But that trend has reversed. Fossil fuel consumption, among other sources of pollution, have resulted in increasing atmospheric and oceanic temperatures, leading to ice sheet melt and unprecedented shifts in our environments.

Hayabusa-2 Sample Return Mission Suggests Protracted Wetter Asteroids

Andy Fell — September 16, 2025 - 4:36pm

New results from the Hayabusa-2 space probe show that asteroids formed at the very beginnings of our Solar System retained substantial amounts of water for hundreds of millions of years, potentially delivering water to Earth and other planets for much longer than previously thought. The work by a large international team, including Professor Qing-Zhu Yin at the �鶹��ý Department of Earth and Planetary Sciences, was published Sept. 10 in Nature.

How Did Animals Eat Before Mouths?

Andy Fell — September 12, 2025 - 11:09am

More than half a billion years ago, during the Ediacaran Period, animal life looked nothing like today. Strange cup- and disk-shaped creatures sat and crawled along an ocean floor covered in thick microbial mats made of bacteria and algae. The only clues these organisms left to their lifestyles exist in the fossil record.

Nowcasting and the Kamchatka Earthquake

Andy Fell — August 07, 2025 - 9:54am

The July 29 earthquake on Russia's Kamchatka peninsula was among the most powerful recorded by modern instruments, setting off tsunami warnings around the Pacific rim. The magnitude 8.8 earthquake caused part of the peninsula to sink by about six feet and set off volcanic eruptions, according to the Unified Geophysical Service of the Russian Academy of Sciences. Fortunately, there do not appear to have been any fatalities or major damage.

Rainy Tropics Could Face Unprecedented Droughts as an Atlantic Current Slows

Andy Fell — July 30, 2025 - 8:00am

New research warns that global rainfall patterns could shift dramatically as a result of climate change

Massive Burps of Carbon Dioxide Led to Oxygen-less Ocean Environments in the Deep Past

Andy Fell — June 23, 2025 - 12:00pm

New research from the University of California, Davis, the Chinese Academy of Sciences and Texas A&M University reveals that massive emissions, or burps, of carbon dioxide from natural earth systems led to significant decreases in ocean oxygen concentrations some 300 million years ago.