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Quantifying the way rivers bend opens up possibility for identifying origins of channels on other planets

Phys.org: Earth science - Wed, 03/05/2025 - 21:37

Whether it's rivers cutting through earth, lava melting through rock, or water slicing through ice, channels all twist and bend in a seemingly similar back-and-forth manner. But a new study led by scientists at The University of Texas at Austin has discovered that channels carved by rivers actually have curves distinct to those cut by lava or ice.

Time will tell: Geoscientists develop tool to chronicle unexplained gaps in the rock record

Phys.org: Earth science - Wed, 03/05/2025 - 21:13

Iron oxide minerals are found in rocks around the globe. Some are magnetic, and some of them rust—especially when exposed to water and oxygen. These characteristics provide clues about the history of these minerals.

New study examines the spread of deep-sea mining sediment plumes

Phys.org: Earth science - Wed, 03/05/2025 - 16:25

On the abyssal plains, at depths between 3,000 and 6,000 meters, polymetallic nodules are scattered across millions of square kilometers, much like potatoes in a field. These mineral ores are formed over millions of years from metals dissolved in the ocean water or released during microbial degradation of organic material in the sediments. As global demand for critical metals, such as nickel, cobalt, and copper, grows, so too does the pressure to exploit these resources economically.

The Antarctic ozone hole is healing, thanks to global reduction of CFCs

Phys.org: Earth science - Wed, 03/05/2025 - 16:00

A new MIT-led study confirms that the Antarctic ozone layer is healing, as a direct result of global efforts to reduce ozone-depleting substances.

How sand mining is eroding rivers, livelihoods and cultures

Phys.org: Earth science - Wed, 03/05/2025 - 15:54

Sand underpins everything from skyscrapers to smartphones. Sharp sand (as opposed to rounded desert sand) is the key ingredient in concrete, while high-purity silica sand is essential for making the silicon chips that power our digital devices.

Supercomputers reveal how small ocean processes influence storms

Phys.org: Earth science - Wed, 03/05/2025 - 14:05

For decades, scientists assumed that only large ocean temperature patterns covering 200 kilometers (124 miles) or more could strongly influence storms. Now, by leveraging advances in computing power, a team of scientists from UC San Diego's Scripps Institution of Oceanography, NASA Jet Propulsion Laboratory and NASA Goddard Space Flight Center have discovered that small-scale ocean processes can have a much larger influence on storm development than previously thought.

Cloud–radiation feedback found to be key to diverse tropical Pacific warming projections

Phys.org: Earth science - Wed, 03/05/2025 - 08:00

New research has uncovered why different climate models offer varying projections of sea surface temperature (SST) changes in the tropical Pacific, a region critical for global climate patterns. The study, published in Advances in Atmospheric Sciences, identifies cloud–radiation feedback as the dominant source behind these differences.

Geodetic model of the 22 January 2024 Mw 7.0 Wushi (northwestern China) earthquake and Mw 5.7 aftershock from inversion of InSAR data

Geophysical Journal International - Wed, 03/05/2025 - 00:00

SummaryOn 22 January 2024, a MW 7.0 earthquake struck the southern sector of the Tian Shan Mountains in Wushi County, northwestern China, causing damage and casualties. In this study, using Interferometric Synthetic Aperture Radar (InSAR) measurements (Sentinel-1 satellites), we constrained the geometry of the fault segment responsible for the seismic event, the coseismic slip distribution, and the source of the subsequent MW 5.7 aftershock deformation. Finally, we evaluated the potential state of stress of the unruptured portions of the causative fault as well as of adjacent fault segments, using the Coulomb stress failure function variations. Our findings indicate rupture along a transpressive left-lateral NNW dipping high-angle fault, associated with the Southern Tian Shan Fault (STF) alignment, likely the Maidan fault, with slip up to 3.5 m only occurring between 10 and 20 km depth. The position of the hypocenter with respect to our estimated slip distribution supports the evidence of a marked bilateral ENE-WSW rupture directivity during the mainshock. The modeling of the postseismic deformation that includes the MW 5.7 aftershock occurred on 29 January 2024, and that is located about 15 km to the south of the mainshock, indicates a main patch with up to 90 cm of slip that may have occurred on a shallow back-thrust segment, in agreement with the observed surface breaks. We propose a potential structural and/or lithological influence on the coseismic rupture extent, consistent with observations from other intracontinental earthquakes. Finally, based on the Coulomb stress distribution computation, we find that the MW 5.7 aftershock was likely triggered by the preceding mainshock and that the Wushi earthquake also increased the stress level at both terminations of the modeled fault plane, particularly along the southwestward continuation of the Maidan fault. In addition, we also find that a wide up-dip fault patch remained unruptured, and considering that these areas have been dynamically loaded it could represent potential further aseismic deformation and/or future significant ruptures, posing a continuing seismic hazard to Wushi County and surroundings areas.

Iron oxides act as natural catalysts to unlock phosphorus to fuel plant growth

Phys.org: Earth science - Tue, 03/04/2025 - 21:30

Northwestern University researchers are actively overturning the conventional view of iron oxides as mere phosphorus "sinks." A critical nutrient for life, most phosphorus in the soil is organic—from remains of plants, microbes or animals. But plants need inorganic phosphorus—the type found in fertilizers—for food.

Agriculture is main cause of seasonal carbon ups and downs, study finds

Phys.org: Earth science - Tue, 03/04/2025 - 20:33

The overall amount of carbon dioxide in the atmosphere has been steadily increasing, a clear trend linked to human activities and climate change. Less concerning but more mysterious, the difference between the highest and lowest amounts of carbon dioxide in the atmosphere each year has also been increasing.