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SummaryWe efficiently extract high-quality Pn wave arrival times from seismograms recorded at recently deployed 120 portable seismic stations of TanluArrays and 317 stations of the Chinese provincial seismic network for 7231 local earthquakes (M >2.0) using the PickNet automatic picking method. Then we use the Pn data to determine 2-D P-wave velocity and anisotropic tomography of the uppermost mantle in and around the Tanlu Fault Zone. Our Pn tomography reveals segmented features of the fault zone, which are well consistent with geological structural features. A continuous low-velocity anomaly parallel to the fault zone is revealed along the Bohai Bay-Weifang, Weifang-Tancheng, and Tancheng-Mingguang segments, whereas the Mingguang-Wuxue segment exhibits a bead-like alternating high and low velocity belt. A similar segmented characteristic also appears in the Pn wave anisotropy in and around the fault zone. A majority of strong earthquakes are located in transitional zones between high and low Pn velocities, suggesting that structural heterogeneities in the uppermost mantle may affect crustal seismogenesis. The low Pn velocities may reflect upwelling of hot and wet upwelling flows in the big mantle wedge due to mantle convection and dehydration of the flat Pacific slab in the mantle transition zone, which cause seismic anisotropy in the upper mantle in and around the Tanlu fault zone.

SummaryEarthquake monitoring plays a critical role in disaster warning and geophysical research, including earthquake phase picking and source parameter estimation. However, traditional methods suffer from cumbersome workflow and challenges in parameter selection during multi-parameter joint estimation. Here, we propose a multitask network for earthquake monitoring that reduces computational complexity by replacing the self-attention mechanism with fast Fourier transform. Through the integration of a fusion module and an enhancement module, the interaction between tasks is strengthened to optimize network performance. Additionally, a dynamic adaptive weight allocation strategy is introduced to achieve a balance among different tasks. The proposed method was trained and tested on the STEAD and INSTANCE datasets and compared with advanced approaches. The results demonstrate that this method outperforms other deep learning methods in earthquake phase picking and source parameter estimation, achieving lower errors and higher evaluation metrics, thus showing potential for practical application in earthquake monitoring.

Online map reveals link between deforestation and rises in tropical temperatures Deforestation is leading to temperature increases of up to 5°C in some tropical regions, according to data revealed in a new interactive map created by researchers at the University of Leeds.

Publication date: Available online 5 November 2025

Source: Advances in Space Research

Author(s): Zhen Lyu, Ningbo Wang, Zishen Li, Zhiyu Wang, Liang Wang, Bingcheng Liu

EU researchers are exploring how undersea communication cables can double-up as environmental and seismic sensors—a potential game-changer for early warning systems.

AbstractMeasurements of the propagation of teleseismic fundamental-mode surface waves are essential for studies of Earth structure and earthquake source processes. Understanding sources of noise and error in these measurements can help improve the accuracy and precision of analyses that use these measurements. One prominent source of noise is interference of overtones with the fundamental mode, which is well-studied in the context of surface wave phase observations. In this work, we show that overtone interference also has a substantial impact on group measurements and has uniquely different characteristics when compared with the analogous interference in phase measurements. We illustrate these characteristics using measurements on both synthetic and real data. Importantly, our experiments suggest that group measurements are more vulnerable than phase measurements to interference from overtones; both synthetic data and published datasets show larger and more variable interference in group measurements than in phase measurements. This interference leads to significant errors in group velocity estimates made using regional or array-based approaches. We show that some quality control measures designed to eliminate overtone interference in phase measurements may not be applicable for group measurements. Our results emphasize the need for careful monitoring of group velocity overtone interference in tomographic imaging, as well as the need for accurate uncertainty quantification when group velocity maps are used in further studies.

AbstractCompared to first-arrival traveltime tomography (FATT), first-arrival traveltime and slope tomography (FASTT) integrates both traveltimes and local slopes of first arrivals at sources and/or receivers to construct more accurate subsurface velocity models. Local slopes serve as additional constraints, helping to mitigate the ill-posedness of tomography by better constraining ray directions. This is particularly beneficial in regions with complex topography, where shadow zones arise due to strong velocity contrasts. However, representing complex topography or bathymetry can be less accurate when using classical rectangular grid discretization. To address these complexities with greater versatility and accuracy, we compute traveltimes of locally coherent events using a factored topography-dependent eikonal solver on curvilinear grids. Slopes are then estimated by finite differences in the traveltime maps after a back-and-forth coordinate transform from the curvilinear grid to a rectangular computational grid. Additionally, we solve the inverse problem with the matrix-free approach, where the data misfit gradient is computed with the adjoint-state method. This adjoint—state formulation avoids the explicit construction and storage of large Fréchet derivative matrices and does not require a tedious posterior ray tracing on curvilinear grids. A land synthetic example first illustrates the sensitivity of slopes to topography and the more accurate velocity models with FASTT than with FATT in the presence of topography. We then perform a first application of the topography-dependent FASTT method on a real redatumed ocean-bottom node dataset, where the bathymetry exhibits a steep scarp. We show that the topography-dependent FASTT generates a velocity model that matches more closely a legacy reflection tomography model than conventional FATT. We conclude that the topography-dependent FASTT provides a versatile approach for handling complex surfaces during velocity model building in both marine and land environments.

In the dense forests of northwestern Pennsylvania, hundreds of thousands of retired oil and gas wells—some dating back to the mid-1800s, long before modern construction standards—dot the landscape, according to geochemists in Penn State's College of Earth and Mineral Sciences who recently led a study in the region. Left uncapped and exposed to air and erosion, they break down, leaching harmful chemicals into the atmosphere and, the researchers reported, into the groundwater.

Publication date: Available online 5 November 2025

Source: Advances in Space Research

Author(s): Yuhao Zheng, Chao Xiong, Gaofang Mi, Yuanqiang Zhao, Ziyuan Zhu, Artem Smirnov, Rui Yan

Publication date: Available online 5 November 2025

Source: Advances in Space Research

Author(s): Dongling Ma, Zhenxin Lin, Qian Wang, Yifan Yu, Guoqiang Yu

Publication date: Available online 5 November 2025

Source: Advances in Space Research

Author(s): Kamyar FULADLU

A team led by LMU researchers shows why CO₂ fluxes from land use are so difficult to quantify—and how they can be estimated more accurately in the future.

Satellite scatterometers play a crucial role in monitoring ocean surface winds, with their accuracy directly impacting weather forecasting and climate research. However, rainfall has consistently challenged precise wind measurements, as Ku-band radar signals are much affected by rain clouds.

Thwaites Glacier in West Antarctica—often called the "Doomsday Glacier"—is one of the fastest-changing ice–ocean systems on Earth, and its future remains a major uncertainty in global sea-level rise projections. One of its floating extensions, the Thwaites Eastern Ice Shelf (TEIS), is partially confined and anchored by a pinning point at its northern terminus.

A new medical study simulated an avalanche in the Italian Alps, demonstrating the life-saving power of a new portable fan system.

The Safeback SBX device weighs 18 ounces, fits into a backpack or vest, and draws oxygen from snowpack’s natural porosity to extend survival. While other safety tools—like emergency beacons and airbags—can make it easier to find someone in an avalanche, the Safeback SBX extends the time a person can survive while waiting for rescue.

“This is the biggest innovation in avalanche safety devices in 25 years.”

In a recent study in the Journal of the American Medical Association (JAMA), the Safeback SBX helped buried victims breathe under the snow for at least 35 minutes. That’s a critically important window. Roughly two thirds of people asphyxiate within 30 minutes of avalanche burial.

“This is the biggest innovation in avalanche safety devices in 25 years,” said Giacomo Strapazzon, an adjunct professor of emergency medicine at the Università degli Studi di Padova and lead author of the study.

Simulating an Avalanche

Strapazzon led the study for the Institute of Mountain Emergency Medicine at the private research center Eurac Research. While the makers of Safeback SBX proposed the study, the research team maintained independence.

To study the efficacy of the device, researchers first needed to bury willing victims. They put out a call for volunteers, screening potential participants for claustrophobia before bringing them to the mountains. They recruited 36 participants, ultimately using 12 men and 12 women, a gender balance celebrated in a separate JAMA editorial for addressing the “severe underrepresentation of females” in high-altitude physiology tests.

The test took place in a mountain pass, 2,000 meters above sea level in the Dolomite range in northeastern Italy. Participants were buried face down under 50 centimeters of high-density snow (500 kilograms per cubic meter) while wearing a Safeback SBX.

In an avalanche, the main cause of death is asphyxiation from lack of oxygen. But snow is naturally porous, up to 67% air even at a density of 300 kilograms per cubic meter. The Safeback SBX uses a large fan to suck oxygen-rich air from the snow behind a victim. It delivers up to 150 liters of air per minute toward the user’s face via shoulder strap tubes. The device works with the company’s backpacks and vests and can be activated before entering avalanche terrains. The equipment is cold weather tested, with a battery lasting at least 60 minutes even at −30°C.

During the test, half the participants received a functioning device that switched off after 35 minutes. The other half received a sham device. Participants were buried one at a time, while a gang of puffy-coat-clad medical professionals monitored their vital statistics from the surface.

The Safeback SBX successfully extended survival time. Of the 12 participants buried with a sham device, only one lasted 35 minutes. Seven had to be rescued after their pulse oximetry, or the level of oxygen in the blood, dipped below the study threshold of 80%. The other four requested an early rescue by radio. Average burial time was 6.4 minutes under the snow.

Of the 12 people buried with a functioning device, 11 lasted the full 35 minutes. Only one requested an early rescue. When the functioning devices were switched off after 35 minutes, participants lasted an average of 7.2 minutes. Five requested rescue, and six required it after their pulse oximetry dropped below 80%.

Winter Work

The device could be valuable for anyone who works and recreates in avalanche terrain, including Earth scientists.

Peter Veals is an atmospheric scientist at the University of Utah. His lab group deploys atmospheric gauges in the Wasatch Mountains each year before the snow falls. But winters are long, and equipment needs maintenance. His team may ski 30 minutes over 4.5 meters (15 feet) of snow to knock icicles off a heated radar dish before a storm starts.

His lab group uses a detailed safety plan, but it’s difficult to avoid avalanche terrain completely, he said. By extending the rescue time, the Safeback SBX has clear value in the mountains.

“Those are some brave volunteers.”

“There’s probably a lot of people that get there a minute too late,” Veals said of avalanche rescues. “Extending [survival time] by 20 minutes plus is a huge deal.”

Other factors affect survivability. People in an avalanche may strike a tree or boulder. Deeper, denser snow would delay a rescue. Preventive measures like avalanche training and education are still essential.

“All those factors mean this isn’t a silver bullet, but I think it is still a huge step forward,” Veals said of the device.

The study did a great job mimicking the conditions of an avalanche, he noted.

“I thought it was as applicable as you could get to the actual situation,” Veals said. “Those are some brave volunteers.”

—J. Besl (@jbesl.bsky.social), Science Writer

Citation: Besl, J. (2025), Safety device supplies life-saving air in an avalanche, Eos, 106, https://doi.org/10.1029/2025EO250418. Published on 7 November 2025. Text © 2025. The authors. CC BY-NC-ND 3.0
Except where otherwise noted, images are subject to copyright. Any reuse without express permission from the copyright owner is prohibited.

Ten years on from the landmark Paris Agreement, countries have taken big strides in limiting emissions and the clean energy transition is accelerating rapidly. But geopolitical headwinds are growing and the damage bill for climate pollution is rising. Climate action hangs in the balance.

A study has revealed that the substantial retreat of the East Antarctic Ice Sheet (EAIS) approximately 9,000 years ago was driven by a self-reinforcing feedback loop between ice melt and ocean circulation.

A landslide in coal waste covering about a square kilometre was triggered by heavy rainfall.

At about 4 am on 4 November 2025, a very large landslide occurred in a coal waste pile at the Mae Moh Mine in Thailand. This is an extremely large coal mining site that is co-located with electricity generating plants.

The landslide itself is very large. EGAT, the owner of the powerplant at the site, has released this image of the aftermath of the failure:-

The 4 November 2025 landslide at Mae Moh Mine in Thailand. Image released by EGAT.

It appears that the landslide occurred in Mae Moh 8 Project area, and that it damaged the offices of Sahakol Equipment Co. Ltd. Google Maps places both of these elements in the area of [18.34735, 99.70067], but the precise location of the landslide is unclear. We will need to wait for a cloud-free day to pin this down more precisely.

News reports indicate that movement was first detected on about 31 October 2025, and that heavy rainfall over the following days led to the failure. The main body of the landslide appears to be mainly translational, although there may be a rotational component in the head scarp area. Displacement near to the crown appears to be several tens of metres at least.

The lowest portions of the landslide have a flow type of mechanism. There may be some pipes on the slope on the right side of the image – it would be interesting to know if these have fed water into the slope.

Newspaper reports cover a statement to the Stock Exchange of Thailand by Sahakol Equipment Public Company Limited:-

“EGAT has declared a state of emergency in the area and has cordoned off the area for safety reasons, forcing the company to temporarily halt work on the Mae Moh 8 project. From a preliminary investigation, the company’s damaged assets include some office buildings and maintenance facilities, some of the Mae Moh 8 project’s soil conveyor belt structures, and other operating machinery.”

This is not the first such failure at Mae Moh mine. In a paper in the journal Engineering Geology, Hoy et al. (2024) describe a 1.2 km long waste dump failure on 18 March 2018. The landslide looks to have been remarkably similar to the event this week.

Reference

Hoy, M. et al. 2024. Investigation of a large-scale waste dump failure at the Mae Moh mine in Thailand. Engineering Geology, 329, 107400. https://doi.org/10.1016/j.enggeo.2023.107400

Return to The Landslide Blog homepage Text © 2023. The authors. CC BY-NC-ND 3.0
Except where otherwise noted, images are subject to copyright. Any reuse without express permission from the copyright owner is prohibited.

SummaryMagma transport in dikes is usually modelled by means of lubrication theory, assuming that magma properties are uniform across the dike. We explore the influence of cross-dike temperature heterogeneity on the dynamics of dike propagation using a quasi-2D model, derived from a full 2D model with an assumption of small width to length ratio. The model couples elastic fracture mechanics with multiphase magma flow, solving the governing equations using a hybrid numerical approach that combines the Displacement Discontinuity Method for elasticity with finite volume discretization for fluid flow and heat transfer. The model includes heat exchange with wall rocks, shear heating and latent heat release. It accounts for non-equilibrium magma crystallization, implementing temperature-dependent crystallization kinetics using an Arrhenius formulation for the relaxation timescale. As a case study, we simulate the ascent of a volatile-rich dacite from a source at 30 km depth. The distribution of temperature, crystallinity, and, thus, viscosity across the dike leads to a plug-like velocity profile with magma stagnation near the walls, substantially different from the parabolic Poiseuille flow assumed in classical lubrication theory. With temperature-dependent crystallization rate, rapid cooling of magma near the dike walls can generate a glassy chilled margin. The adjacent magma has higher crystallinity due to intermediate cooling rates, while the hotter core remains depleted in crystals throughout dike propagation. The dike propagates further and is thinner than predicted by (1D) lubrication theory because the low-viscosity core continues to facilitate vertical transport while the wall zones become progressively more viscous due to cooling and crystallization. The latent heat of crystallization can have a substantial impact in slowing down cooling and prolonging propagation. Other important factors include the characteristic crystal growth time, initial magma temperature and water content. Our quasi-2D approach bridges the gap between oversimplified 1D models and computationally expensive 3D simulations, providing a practical framework for investigating magma transport in silicic dikes.

SummaryThe 1957 Andreanof, Aleutian Is., earthquake (1957 March 9, 51.53°N, 175.63°W, d=25 km) is among the most enigmatic great earthquakes instrumentally recorded. The length of the aftershock area is very long (about 1,200 km), and tsunami excitation has been recently confirmed to be very extensive, yet its instrumental seismic magnitude Ms is only about 8.1 to 8.3. Detailed analyses of long-period surface waves in the past gave an Mw=8.4, and the seismic-tsunami disparity remains unresolved. The main difficulty in seismic studies is the absence of high-quality seismic data. Here we investigate the cause of this disparity by carefully analyzing some historical seismograms with modern digitization methods. We also take advantage of the 1996 Aleutian Is. earthquake (Mw=7.87) that occurred very close to the 1957 event. For the 1996 event, high-quality modern broad-band seismograms are available which can be effectively used as empirical Green’s functions for the analysis of the 1957 event. Using the Wiechert (Strasbourg, Uppsala), Milne-Shaw (Wellington), and Benioff (Uppsala, Pasadena) seismograms of the 1957 event, we could determine that the 1957 event had significant secondary excitation of long-period (150 s) waves during about 1,000 s following the first event. The Mw of the combined source is approximately 8.4. Because of the limited bandwidth of the old instruments, we cannot detect long-period energy beyond 150 s. However, the unusually long-lasting excitation over nearly 1,000 s suggests that the event had significant excitation at periods longer than 150 s with a much larger Mw for the total event. Although we cannot address this question quantitatively because of our band-limited data, our numerical experiment using a source with a slow component shows that if the time scale of the slow source is longer than 500 s, our data can be made compatible with an Mw =8.8 to 8.9 event, thereby reconciling the results from seismic and tsunami data.