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Study uncovers mineral 'sink' that reduced phosphorus in early oceans, potentially delaying Earth's oxygen rise

Phys.org: Earth science - Thu, 03/19/2026 - 17:40

Scientists have long sought to explain a key mismatch in Earth's early history: oxygen-producing photosynthesis evolved hundreds of millions of years before atmospheric oxygen began to rise during the Great Oxidation Event. This delay has been linked to limited phosphorus—a nutrient essential to life—but the specific processes controlling phosphorus availability in the iron-rich oceans of Archean Earth (approximately 3.2–2.5 billion years ago) remained unclear.

Ancient brines helped build Idaho's Silver Valley and Cobalt belt

Phys.org: Earth science - Thu, 03/19/2026 - 16:00

Idaho's Silver Valley has produced about 1.2 billion ounces of silver since the late 1800s, enough to cast a solid cube roughly as tall as a five-story building, along with huge amounts of lead and zinc. Now a new study led by Washington State University researchers helps explain how mineral deposits in the Silver Valley and other mineralized parts of the Belt Supergroup began to form more than 1.2 billion years ago. The Belt Supergroup is a massive stack of rocks stretching across eastern Washington, Idaho, and Montana that also hosts the Idaho Cobalt Belt, the most significantly mineralized cobalt district in the United States.

Effect of Singularity Point in Layered Anisotropic Media

Geophysical Journal International - Thu, 03/19/2026 - 00:00

SummaryThe singularity points are very common in the low-symmetry anisotropic media. The presence of these points results in complications of the wave fronts (or group velocity images) for waves forming the singularity points. We show the effect of singularity points in multilayered anisotropic media with triclinic symmetry.

Insights from complex conductivity monitoring data for modelling of CaCO3 precipitation in sandstones

Geophysical Journal International - Thu, 03/19/2026 - 00:00

SummaryQuantification and control of the in situ mechanics of calcite precipitation in the subsurface are notorious problems often encountered in hydrogeological and engineering applications. Difficulties arise here due to the general inaccessibility and texture of pore spaces, as well as the precipitation reaction’s dependence on fluid chemistry and the composition of the pore surfaces. To mitigate the uncertainties introduced by these inaccessible variables, we propose the use of spectral induced polarization (SIP) as a non-invasive tool to gain insight into the textural and electrochemical parameters controlling the precipitation rate within confined pore spaces and incorporate the gained information into a reactive transport model for quantification. We present SIP monitoring data from three laboratory experiments on diffusive mixing, inducing CaCO3 precipitation in sandstone. During the experimental runs, we identify a clear pattern showing the onset of the chemical reaction in the low-frequency (< 0.1 Hz) response of the imaginary conductivity and the formation of an associated high-frequency peak (> 10 Hz) in the later stages of the experiment. The changes to pore space geometry and precipitation yield were estimated with multiple independent methods. Using information gained from the monitoring data, we predict the dynamics of the precipitation reaction by including textural information, the inner surface area, and the grain size of the precipitate, as well as constraints on the effective diffusivity. These parameters were determined for each sample, based on empirical relations to the polarization response, and incorporated into an accompanying reactive transport model (phreeqc). The experimental results highlight the benefits SIP monitoring can provide to reactive transport models, even if precipitation yield is close to the detection limit of commonly applied methods, such as X-ray powder diffraction or fluorescence.

New ice core studies expand histories of greenhouse gases and ocean temperature to 3 million years

Phys.org: Earth science - Wed, 03/18/2026 - 23:20

New analyses of ancient ice from Antarctica and the air contained inside it are extending the history of Earth's climate records and expanding researchers' understanding of how the planet has changed over the last 3 million years.

Ancient climate records reveal a wetter Levant that may have guided early humans out of Africa

Phys.org: Earth science - Wed, 03/18/2026 - 22:40

For modern residents of the Levant, the "Red Sea Trough" usually brings a brief, dusty transition between seasons. But 127,000 years ago, this same weather pattern may have been the literal key to human history. A new study, led by Ph.D. student Efraim Bril, Prof. Adi Torfstein and Dr. Assaf Hochman from the Institute of Earth Sciences at the Hebrew University of Jerusalem and published in Climate of the Past, reveals that during the Last Interglacial (LIG) peak, the Levant wasn't just a dry bridge between continents, it was dynamic with more relatively wet conditions fueled by intense, localized rain. This shift in ancient weather likely provided the water sources necessary for early humans to successfully migrate "out of Africa."

Satellite data reconstruct 2025 LA fires, showing rapid spread in first day

Phys.org: Earth science - Wed, 03/18/2026 - 21:00

A severe drought, powerful Santa Ana winds and a not-fully-extinguished brushfire combined to create the most destructive wildfire in the history of Los Angeles in early 2025. The Palisades Fire, which fully ignited on Jan. 7, destroyed Los Angeles' Pacific Palisades neighborhood, killing 12 people and burning 6,800 homes and buildings.

New approach improves precipitation accuracy for hydrological models

Phys.org: Earth science - Wed, 03/18/2026 - 21:00

Hydrological models represent water movement in natural systems, and they are important for water resource planning and management. But the models depend on reliable input data for weather factors, and precipitation can be very difficult to measure and represent accurately. A recent study in Environmental Modelling & Software by an international research team describes a novel method to better represent precipitation uncertainty in hydrological models, thereby improving their performance.

Anomalous lepton acceleration in the radiation reaction dominated reflection regime

Physical Review E (Plasma physics) - Wed, 03/18/2026 - 10:00

Author(s): Xiaofei Shen, Yue-Yue Chen, Karen Z. Hatsagortsyan, and Christoph H. Keitel

Relativistic electrons colliding with intense counterpropagating laser pulses are expected to lose energy through radiation reaction. However, we reveal a counterintuitive regime where reflected leptons (including incident electrons, generated electrons, and positrons) gain significant energies when…

[Phys. Rev. E 113, 035208] Published Wed Mar 18, 2026