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New deep-sea measurements show how the ocean floor forms

Phys.org: Earth science - Wed, 07/08/2026 - 22:00
The first-known direct observations of a seafloor spreading event at a mid-ocean ridge in the Indian Ocean are presented in Nature. The observations offer insight into how new oceanic crust is created.

Scientists find gas emissions from rocks may have contributed to ancient climate swings, mass extinctions

Phys.org: Earth science - Wed, 07/08/2026 - 18:00
An interdisciplinary team from Florida State University's Department of Earth, Ocean, and Atmospheric Science has uncovered new evidence about processes that may have contributed to ancient mass-extinction events, some of the most dramatic ecosystem reorganizations in Earth's history.

More than 90% of key nutrients degrading the Mar Menor lagoon come from recirculated underground flows

Phys.org: Earth science - Wed, 07/08/2026 - 16:40
More than 90% of the key nutrients degrading the Mar Menor, such as ammonium, phosphorus and silica, do not come from streams or continental groundwater, but rather through a mechanism that has so far been overlooked: Water from the lagoon itself infiltrates the sediments and re-emerges loaded with nutrients that have accumulated over years. This is the conclusion of a recent study carried out by the Institute of Environmental Science and Technology of the Universitat Autònoma de Barcelona (ICTA-UAB), Spain, which questions the current restoration strategies for the Mar Menor because they do not take this pathway of contamination into account.

Nanoplastics found in Antarctic soils for first time, suggesting long-range atmospheric transport

Phys.org: Earth science - Wed, 07/08/2026 - 16:30
Microplastic contamination has been a much-discussed topic over the last several years, but contamination from even smaller plastic particles represents another pressing issue. Nanoplastics—defined as being under a micrometer in diameter—may pose an even higher ecological risk because they can travel more easily, cross cellular membranes and easily adsorb other pollutants.

Ancient atmospheric oxygen found in iron ore deposits

Phys.org: Earth science - Wed, 07/08/2026 - 14:40
How do some of geology's most mysterious iron ore deposits form? This question has preoccupied the geosciences for more than a century. An international research team led by Dr. Stefan Peters from the Leibniz Institute for the Analysis of Biodiversity Change (LIB) has discovered that major iron ore deposits contain traces of oxygen inherited from Earth's ancient atmosphere. The study, now published in Nature Communications, shows that oxygenation of the atmosphere by photosynthesis played a crucial role in the formation of these deposits.

Spatially resolved temperature measurement and axial thermal transport assessment of magnetized-liner-inertial-fusion burning plasmas

Physical Review E (Plasma physics) - Wed, 07/08/2026 - 10:00

Author(s): J. T. Clapp, R. C. Mancini, E. Gallardo-Diaz, E. C. Harding, and A. J. Harvey-Thompson

In a series of magnetized-liner-inertial-fusion experiments performed at the Z pulsed power facility of Sandia National Laboratories, beryllium liners filled with deuterium gas densities between 0.7 to 1.4 mg/cc and a tracer amount of krypton were imploded. At the collapse of the cylindrical implosi…


[Phys. Rev. E 114, 015205] Published Wed Jul 08, 2026

Long-duration quiescent high-$β$ hydrogen plasmas

Physical Review E (Plasma physics) - Wed, 07/08/2026 - 10:00

Author(s): S. A. Cohen, L. David, S. P. Vinoth, C. P. S. Swanson, and E. Ho

Radiofrequency-heated, high-β, magnetized hydrogen plasmas in the Princeton field-reversed-configuration-2 device, with its magnetic-field-parallel radial boundary formed by eight discrete room-temperature coaxial copper rings, display constant density for times exceeding 150 ms. When the copper rin…


[Phys. Rev. E 114, 015206] Published Wed Jul 08, 2026

A Self-supervised Swin-Unet Method for Ground Roll Suppression Based on Fourier Positional Encoding and Masking Strategy

Geophysical Journal International - Wed, 07/08/2026 - 00:00
SummaryTo address the challenge in seismic exploration where strong-energy ground roll severely interferes with effective signals and conventional suppression methods tend to damage these signals, this paper proposes a self-supervised Swin-Unet network method for ground roll suppression based on Fourier Positional Encoding and a bespoke masking strategy. This method operates without the need for clean label data. By employing a specially designed fan-shaped masking strategy, it disrupts the spatio-temporal coherence of the ground roll, thereby guiding the network to learn the intrinsic characteristics of the effective signals and reconstruct the data. The core innovation lies in the introduction of Fourier Positional Encoding, which overcomes the inherent low-frequency bias of the Transformer architecture. This significantly enhances the network’s capability to model and recover high-frequency effective signals. Experimental results on synthetic data and field 2D/3D seismic datasets demonstrate that the proposed method not only effectively suppresses strong ground roll but also surpasses the traditional f – k filtering method in terms of signal fidelity, particularly in preserving deep, weak reflections and high-frequency components. This showcases its robustness and potential for application in complex seismic data processing.

Mesh-free stress solution for complex 3D reservoir simulation grids: a mixed nuclei of strain and analytical element approach

Geophysical Journal International - Wed, 07/08/2026 - 00:00
SummaryAn innovative method is presented for full 3D pressure and temperature dominated stress evaluations in the subsurface using tetrahedra-based analytical elements combined with the inflation point source solution. A mesh-free approach suitable to industry standard 3D flow simulation models (based on hexahedral cells) is obtained by representing the grid cells in tetrahedral elements, effectively preserving the 3D geometrical complexities of the reservoir. Contributions from neighboring grid cells are added via a Tartan grid representation of point sources that enables the spatial resolution to increase and the stress evaluations to be carried out in parallel, both of which significantly improve computational efficiency. The novel approach is demonstrated for synthetic low enthalpy geothermal models with clastic reservoir characteristics and varying degrees of geometrical and structural complexity. The method is shown able to accurately capture the effects of stress arching on complex faults causing reservoir throw and flow compartmentalization, and along the rim of the cold-water volume. Results of a synthetic geothermal development model of the heavily faulted Gullfaks field show the novel method to provide an accurate and computationally highly efficient approach for evaluating pressure and temperature dominated stress changes in structurally complex sedimentary reservoirs.

Induced polarization of cementitious materials. Part II. Monitoring their hydration phase

Geophysical Journal International - Wed, 07/08/2026 - 00:00
SummaryPore-water pressure and clay content have influence on porosity and bonding/cementing the grain boundaries, thus affecting elastic properties, strength, and other physical properties of rocks. Similar processes take place in cementitious materials, where in particular hydration plays crucial role. This process leads to changes in pore water composition, specific surface area (or alternatively Cation Exchange Capacity, CEC), and water content. Analytical expressions can be obtained between both the CEC and porosity and a hydration state variable. The hydration state variable can be in turn related to the hydration time. These phenomena can be assessed by geoelectrical methods, which have been used for a long time to observe the evolution of the textural properties and rheology of rocks, as well as of cementitious materials. However, such use has been so far rather qualitative. The aim of this study is to better describe the evolution of complex conductivity spectra (induced polarization) in relation to the hydration, using the recently developed dynamic Stern layer model to the hydration time through Powers model. Comparisons between the model predictions and literature data are used to test the suitability of the proposed solution. The model is verified using monitoring experiments of the complex conductivity spectra of several cements to study the evolution of both the in-phase and quadrature conductivity versus the hydration time. Although the current method is still semi-empirical, it makes it possible to analyze and understand the evolution of complex conductivity spectra of geomaterials and technogenic cementitious materials with a wide variety of geophysical applications in civil engineering, especially for dams and underground civil constructions.

Efficient Bayesian inference through self-supervised active learning

Geophysical Journal International - Wed, 07/08/2026 - 00:00
SummaryWe have developed a physics-guided deep learning framework for geophysical inversion that incorporates Markov chain Monte Carlo (MCMC) sampling to assess the uncertainty associated with model parameters of interest. To enhance computational efficiency, a statistical sampling method is utilized to reduce the number of samples required while ensuring the training data remain both diverse and informative. As the inversion progresses iteratively, the training dataset is dynamically expanded using outputs from the stochastic sampler along with their corresponding forward responses. A supervised deep learning model is utilized, in which the Jensen-Shannon divergence is adopted as the loss function, and a Gaussian assumption is applied for analytical computation. We test the workflow on a seismic velocity model inversion, and successfully capture the geological features and velocity distributions, with results that closely match the reference model. Compared to the MCMC sampler applied to the whole data cube, the proposed workflow is more computationally efficient, as a small fraction of data is chosen using the active learning paradigm. This workflow is strongly generalizable and effective, making it suitable for a wide range of other inversion applications as well.

Satellite record reveals US tidal wetland productivity rose 6% in 20 years

Phys.org: Earth science - Tue, 07/07/2026 - 21:40
Carbon sequestration, climate regulation, biodiversity support and shoreline protection: These are all benefits provided by tidal wetlands. As the climate changes, the amount of carbon captured by these vital ecosystems may be changing as well.

Day-night ocean warming helps explain why El Niño outpaces La Niña in models

Phys.org: Earth science - Tue, 07/07/2026 - 19:20
Researchers have long known that there is an asymmetry in the El Niño-Southern Oscillation (ENSO), the confluence of wind and water currents that creates warm El Niño events and cooler La Niña events. Large-scale climate models tend to underrepresent this asymmetry for reasons that are still not fully understood. Better modeling of the mechanisms that make El Niño events warmer could both provide insight into Earth's climate system and improve future ENSO predictions.

Isotopic signatures link hot spring magmatic water to the subducting Pacific Plate

Phys.org: Earth science - Tue, 07/07/2026 - 12:09
Water flowing from hot springs near volcanoes often contains a mixture of meteoric water that has percolated underground and a deeper component known as magmatic water. Researchers at the University of Tsukuba used numerical simulations and isotopic data to show that magmatic water in hot springs and volcanic gases around Kussharo Caldera, Hokkaido, originates from the subducting Pacific Plate, which descends from the Kuril Trench to a depth of 125 kilometers (78 miles). The paper is published in the Journal of Volcanology and Geothermal Research.

New research finds connection to place predicts hurricane response among US coastal residents

Phys.org: Earth science - Tue, 07/07/2026 - 12:00
For U.S. coastal residents, storm surge is among the deadliest hurricane hazards, causing catastrophic property damage and loss of life, and scientists expect tropical storms to grow more intense. During Hurricane Ian in 2022, storm surge accounted for 41 of the 66 direct deaths. The 2026 Atlantic hurricane season is now underway, and while NOAA expects below-normal activity, emergency managers caution that it only takes one storm to devastate a community.

Massive calving episode in Greenland may foreshadow more rapid ice sheet loss

Phys.org: Earth science - Tue, 07/07/2026 - 11:40
In November 2025, a study led by Adrien Wehrlé, a researcher in the Department of Geography at the University of Zürich, Switzerland, looked at the massive calving response of one of West Greenland's active glaciers, Sermeq Kujalleq in the Kangia icefjord (SKK), to the drainage of two surface lakes. Called supraglacial lakes, these are temporary meltwater ponds that form and accumulate in depressions or holes on the surface of glaciers and ice sheets.

Ancient rocks reveal how water reshaped Earth's interior 3.1 billion years ago

Phys.org: Earth science - Tue, 07/07/2026 - 09:00
Geologists studying some of the planet's oldest volcanic rocks have uncovered new evidence that water was playing a major role in shaping Earth's interior and driving volcanic activity more than 3 billion years ago.

Newly discovered mineral named for researcher Tyler Spano

Phys.org: Earth science - Tue, 07/07/2026 - 03:20
Tyler Spano's impact on the field of mineralogy is anything but small. So when a newly discovered mineral, modest in size but significant in meaning, was named spanoite in her honor, it became a fitting tribute to her contributions to the field.

Soil thickness controls landslide occurrence, study finds

Phys.org: Earth science - Tue, 07/07/2026 - 01:00
Researchers at University of Tsukuba analyzed high-resolution topographic data from airborne LiDAR to examine the relationships among landslide area, depth, and slope gradient.

On the origin of mid-mantle discontinuities beneath the Central Pacific as revealed by long-period SS and PP precursors

Geophysical Journal International - Tue, 07/07/2026 - 00:00
SummaryThe origin of seismic discontinuities in the Earth’s mid-mantle (∼700–1400 km) remains debated, with competing hypotheses attributing them to either partial melting due to water transport across the transition zone or compositional heterogeneities (subducted crust). Distinguishing between these scenarios has been hindered by the inability of standard imaging techniques to extract robustly the polarity of weak seismic reflections amidst noise and reverberations that contaminate mid-mantle reflections. Here, we introduce a novel signal processing framework that combines curvelet-based wavefield separation with extended multitaper deconvolution to resolve this polarity ambiguity. We validate this approach by applying it to a high-quality dataset of SS and PP precursors beneath the Central Pacific. This application yields the robust detection of a discontinuity at approximately 800 km depth, characterized by a sharp positive shear velocity contrast (δVS ≈ +4 − 5%) and a negligible density contrast. The observed positive polarity precludes partial melt or thermal plumes as primary causal mechanisms. Instead, the high-velocity, neutral-density signature is consistent with a layer of stagnant, subducted oceanic crust in thermal equilibration with the ambient mantle. These results demonstrate the efficacy of the deconvolution framework and provide direct seismic evidence for compositional stratification in the mid-mantle, supporting geodynamic models where viscosity increases facilitate the long-term preservation of recycled lithosphere.

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