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Publication date: 15 August 2025

Source: Advances in Space Research, Volume 76, Issue 4

Author(s): Gholamali Dastbala, Maryam Dehghani, Ayoub Karimi-Jashni

Publication date: 15 August 2025

Source: Advances in Space Research, Volume 76, Issue 4

Author(s): M. Pedreros-Guarda, R. Abarca-del-Río, J.F. Crétaux, A. Paris

Publication date: 15 August 2025

Source: Advances in Space Research, Volume 76, Issue 4

Author(s): Na Li, Zhen Li

Publication date: 15 August 2025

Source: Advances in Space Research, Volume 76, Issue 4

Author(s): Yingchun Yue, Yixuan Wang, Ming Shangguan, Xiao Xu, Yifan Liang, Shaofeng Bian, Guojun Zhai

Publication date: 15 August 2025

Source: Advances in Space Research, Volume 76, Issue 4

Author(s): Yuxin Liu, Xinzhi Wang, Yi Zhou, Atta ur Rahman

Publication date: 15 August 2025

Source: Advances in Space Research, Volume 76, Issue 4

Author(s): Huizhong Zhu, Guangsheng Liu, Xiang Gao, Shuaimin Wang, Chunhua Jiang

Human activities, such as deforestation and the expansion of agricultural areas, have a massive impact on the natural state of ecosystems. As a result, large amounts of carbon are released into the atmosphere, contributing substantially to anthropogenic climate change.

About 1.1 billion years ago, the oldest and most tectonically stable part of North America—called Laurentia—was rapidly heading south toward the equator. Laurentia eventually slammed into Earth's other landmasses during the Grenville orogeny to form the supercontinent Rodinia.

Researchers from the UCLA Samueli School of Engineering and their collaborators have developed FuelVision, a new system that could help enhance nationwide wildfire preparedness by combining satellite imagery with artificial intelligence to rapidly and accurately identify wildfire fuel sources.

Cultural burning is an Indigenous community-based practice where controlled fire is used to manage landscapes like forests. These work by reducing dried, flammable vegetation in a manageable way.

Off the southern coast of Chile, three tectonic plates meet at a point known as the Chile Triple Junction. Two are oceanic plates, the Nazca and the Antarctic, which are separating in an active spreading center, creating a mid-ocean ridge between them. At the same time, both plates—spreading ridge included—are sliding into the mantle beneath a third plate, the South American. The Chile Triple Junction is the only place on Earth where an active spreading center is subducting under a continental plate.

Source: Journal of Geophysical Research: Solid Earth

Around 1.1 billion years ago, the oldest and most tectonically stable part of North America—called Laurentia—was rapidly heading south toward the equator. Laurentia eventually slammed into Earth’s other landmasses during the Grenville orogeny to form the supercontinent Rodinia.

Laurentia’s path during that period is known, thanks to paleomagnetism. By tracing the orientation and magnetism of rocks in the lithosphere, scientists can approximate the relative position and movement of Laurentia leading up to Rodinia’s formation.

The rocks along Lake Superior in northern Wisconsin and Michigan are especially important for tracing Laurentia’s movement. These rocks—dominated by red sandstones, siltstones, and minor conglomerates—were deposited during extensive sedimentation caused by the North American Midcontinent Rift and are rife with iron oxides like hematite. Hematite can acquire magnetization when it is deposited, which records where the rock was in relation to Earth’s poles at the time.

Unfortunately, the existing paleomagnetic record is marred by a gap between 1,075 million and 900 million years ago, limiting our understanding of how, when, and where Rodinia formed.

To fill this data gap, Fuentes et al. collected new samples from the Freda Formation near Lake Superior, which formed in floodplain environments an estimated 1,045 million years ago. The authors combined these data with stratigraphic age modeling to estimate a new, sedimentary paleopole, or the position of the geomagnetic pole at a particular time in the past.

Previous studies indicate that for 30 million years, sometime between 1,110 million and 1,080 million years ago, Laurentia moved from about 60°N to 5°N at a rate of 30 centimeters (12 inches) per year—faster than the Indian plate’s collision with Eurasia pushing up the Himalayas. This study showed that over the following 30 million years, Laurentia’s progress slowed to 2.4 centimeters (1 inch) per year as it crossed the equator.

The paleocontinent’s slowdown during Freda Formation deposition coincides with the onset of the Grenville orogeny. The results confirm that a stagnant single-lid regime—in which the lithosphere behaves as a single, continuous plate rather than multiple independent plates—was not in effect during this interval. (Journal of Geophysical Research: Solid Earth, https://doi.org/10.1029/2025JB031794, 2025)

—Aaron Sidder, Science Writer

Citation: Sidder, A. (2025), Lakeside sandstones hold key to ancient continent’s movement, Eos, 106, https://doi.org/10.1029/2025EO250304. Published on 18 August 2025. Text © 2025. AGU. 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.

Editors’ Highlights are summaries of recent papers by AGU’s journal editors. Source: Tectonics

How do we detect past fault slip in slowly deforming regions like the Eastern Alps, where modern earthquakes are infrequent and geologic markers of seismicity are subtle or absent?

Prince et al. [2025] tackle this challenge using two innovative dating techniques: optically stimulated luminescence (OSL) and electron spin resonance (ESR). These “trapped charge” methods harness electrons that are caught in crystal defects or impurities in quartz or feldspar grains but can be released by stimuli such as light or heat. Here, the authors target quartz and feldspar in crushed fault rocks, or fault gouge. During an earthquake, work done to overcome the frictional strength of fault rocks is given off in the form of heat that may “reset” the OSL and ESR systems.

The authors compare ESR and OSL signals from fault gouges from three faults in the Eastern Alps: the Šoštanj, Periadriatic, and Lavanttal faults. They also quantify the ESR signal saturation, which gauges how close the trapped electron system is to its maximum capacity. Their results indicate that the Periadriatic and Šoštanj faults were active during the Quaternary period (the past about 2.6 million years). The Šoštanj fault shows evidence for the most recent activity, with OSL dates as young as about 30,000 years and low ESR saturation levels suggesting repeated signal resetting. In contrast, the Lavanttal fault gouge exhibits saturated ESR signals with dates ranging from about 860,000 to over 2 million years. These results imply the Lavanttal fault was seismically quiescent during the Quaternary, or the conditions of fault slip did not yield sufficient temperatures to reset the trapped charge systems.

This study spotlights the growing utility of trapped charge dating for documenting the slip histories of faults with or without historical seismicity. The analytical uncertainty of any trapped charge date (see figure above) far exceeds an individual or multiple earthquakes, and fault-slip temperatures at shallow depths can be insufficient to completely reset these systems, so it is challenging to fingerprint individual earthquakes with this approach. However, by harnessing the complementary strengths of OSL and ESR together with ESR saturation levels, the authors are able to reconstruct a fuller picture of the timing and distribution of shallow fault slip, which is critical for understanding regional tectonics and assessing seismic hazard.

Citation: Prince, E., Tsukamoto, S., Grützner, C., Bülhoff, M., & Ustaszewski, K. (2025).  Deciphering Pleistocene fault activity in the Eastern Alps: Dating fault gouges with electron spin resonance and optically stimulated luminescence. Tectonics, 44, e2024TC008662. https://doi.org/10.1029/2024TC008662

—Alexis Ault, Associate Editor, Tectonics

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.

A series of more than 100 earthquakes has hit Northern California, shaking up the Geysers geothermal steam field in Sonoma and Lake counties.

Author(s): Zachary A. Johnson, Nathaniel R. Shaffer, and Michael S. Murillo

Laboratory plasma production almost always preferentially heats either the ions or electrons, leading to a two-temperature state. In this state, density functional theory molecular dynamic simulation is the state of the art for modeling bulk material properties. We construct a statistical mechanics …

[Phys. Rev. E 112, 025207] Published Mon Aug 18, 2025

Heat waves are becoming more common, severe and long-lasting. These prolonged periods of hot weather are especially dangerous in already hot places like Texas. In 2023, more than 300 people in Texas died from heat, according to the Texas Department of State Health Services, the most since the state began tracking such deaths in 1989. Researchers found it may not only be temperatures that make heat waves unsafe but also the heat-related increase in airborne pollutants.

At least 43 people were killed in devastating landslides and debris flows in northern China. Planet Labs images provide an insight into this disaster.

It is extremely challenging to keep up with the landslides occurring around the world at the moment. There has been a lot of attention paid to the remarkable rock slope failure and tsunami in Alaska. I feel that others are better placed to write about that (although I will probably continue to highlight updates via my BlueSky account), but if you get a chance please take a look at the images on the Alaska News Source website.

There have also been a devastating set of debris flows in northern Pakistan and parts of India and Nepal. At this stage, it is a little unclear to me as to the full extent of these events (especially in Pakistan) – I am likely to return to this theme.

Often the best way to understand an event is to piece together the news reports with satellite images when they become available. And so, let’s take a look at reported “floods” or “flash floods” (actually landslides and channelised debris flows) that occurred in Yuzhong County in Gansu Province in China on 7 August 2025. The BBC has a good report of the aftermath, whilst Al Jazeera reports 10 dead and 33 missing from this event. We must take reports of losses in China with a large pinch of salt.

The location of the source of this event is [35.71498, 104.02436]. So here is a Planet Labs image, dated 30 July 2025, showing the area affected. The marker is at the location highlighted above:-

Planet Labs image of the source of the 7 August 2025 landslides and debris flows in Yuzhong County, Gansu Province. Image copyright Planet Labs, used with permission. Image dated 30 July 2025.

And here is the same location after the event:-

Planet Labs image of the aftermath of the 7 August 2025 landslides and debris flows in Yuzhong County, Gansu Province. Image copyright Planet Labs, used with permission. Image dated 13 August 2025.

And here is a slider to allow you to compare the images:-

Images copyright Planet Labs.

This is a closer look at this area of intense landslides:-

Planet Labs image of the aftermath of the 7 August 2025 landslides and debris flows in Yuzhong County, Gansu Province. Image copyright Planet Labs, used with permission. Image dated 13 August 2025.

What we see here is literally hundreds of shallow failures that will have occurred almost simultaneously, and then combined to form devastating channelised debris flows. There are many failures on the slopes to the southwest, but the greatest concentration is to the northwest is an area that is densely vegetated.

This is indicative of extremely high rainfall intensities, but this storm was highly localised. The area of intense landslides is only about 9 km x 5 km.

The downstream impacts were terrible. These are the settlements immediately to the east of the landslides:-

Planet Labs image of the downstream area affected by the 7 August 2025 landslides and debris flows in Yuzhong County, Gansu Province. Image copyright Planet Labs, used with permission. Image dated 30 July 2025.

And here is the same area after the landslides:-

Planet Labs image of the downstream area affected by the 7 August 2025 landslides and debris flows in Yuzhong County, Gansu Province. Image copyright Planet Labs, used with permission. Image dated 13 August 2025.

And again, here is a slider to allow the images to be compared:-

Images copyright Planet Labs.

There is a large number of destroyed buildings in this imagery. The devastation extended for a considerable distance.

Reference

Planet Team 2025. Planet Application Program Interface: In Space for Life on Earth. San Francisco, CA. https://www.planet.com/

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.

AbstractSeismology has entered the petabyte era, driven by decades of continuous recordings of broadband networks, the increase in nodal seismic experiments, and the recent emergence of Distributed Acoustic Sensing (DAS). This review explains how cloud platforms, by providing object storage, elastic compute, and managed databases, enable researchers to “bring the code to the data,” thereby providing a scalable option to overcome traditional HPC solutions’ bandwidth and capacity limitations. After literature reviews of cloud concepts and their research applications in seismology, we illustrate the capacities of cloud-native workflows using two canonical end-to-end demonstrations: 1) ambient noise seismology that calculates cross-correlation functions at scale, and 2) earthquake detection and phase picking. Both workflows utilize Amazon Web Services, a commercial cloud platform for streaming I/O and provenance, demonstrating that cloud throughput can rival on-premises HPC at comparable costs, scanning 100 TBs to 1.3 PBs of seismic data in a few hours or days of processing. The review also discusses research and education initiatives, the reproducibility benefits of containers, and cost pitfalls (e.g., egress, I/O fees) of energy-intensive seismological research computing. While designing cloud pipelines remains non-trivial, partnerships with research software engineers enable converting domain code into scalable, automated, and environmentally conscious solutions for next-generation seismology. We also outline where cloud resources fall short of specialised HPC-most notably for tightly coupled petascale simulations and long-term, PB-scale archives-so that practitioners can make informed, cost-effective choices.

SummaryThe 1985 Mw 6.9 Wuqia earthquake, one of the strongest instrumentally recorded seismic events in the Pamir foreland thrust system, caused significant surface ruptures. The Pre-earthquake KH-9 and post-earthquake WorldView-3 and SPOT-6 satellite images are used to investigate the fault rupture and slip behavior of this earthquake. We revealed a more detailed ∼22 km long displacement belt beyond the previously documented ∼15 km rupture, using optical image correlation with sophisticated error post-processing. Several new fractures in western segment are identified which are confirmed in the displacement map. A comprehensive analysis of the strike change, near-surface dip and cross-fault offsets shows a ∼1.6 km dextral strike-slip tearing fault resulted from the heterogeneous strain release. Based on the empirical scaling relationship, a down-dip rupture width of 10.55 km is estimated using the observed rupture length and inverted slip. Combined with the previously published 3D fault geometry based on seismic imaging, we suggest that the 1985 Wuqia earthquake ruptured only the upper ramp. This study provides precise constraints on surface rupture characteristics, and new insights into the complex rupture pattern of a thrust-type earthquake within the tectonically active Pamir foreland region.

SummaryUnderstanding the geophysical drivers of seasonal geocenter motion (GCM) variations remains challenging due to the complexity of Earth system interactions, limited data on individual mass redistribution components, and model uncertainties. This study presents a comprehensive investigation of seasonal GCM signals from April 2002 to January 2024 using the Fingerprint Approach (FPA), which enables direct quantification of contributions from distinct Earth system components. Additionally, Multichannel Singular Spectrum Analysis (MSSA) is applied to quantify the influence of terrestrial water storage (TWS), atmosphere (ATM), and ocean (OCN) variability on seasonal GCM fluctuations. Correlation and lag analyses are employed to explore their temporal relationships and underlying geophysical linkages. The results reveal that TWS, ATM, and OCN jointly explain 97.9 per cent, 98.1 per cent, and 90.8 per cent of the seasonal variance in the X, Y, and Z components of GCM, respectively. TWS exerts as the dominant contributor in the Y (66.4 per cent) and Z (67.9 per cent) components, while ATM and OCN each contribute less than 49 per cent in all components. Further analysis indicates that ATM, OCN, and TWS exhibit varying lag relationships with GCM in the X and Z components, while TWS demonstrates a notably stronger correlation with GCM in the Y component. Importantly, an approximately 120-day periodic signal identified in GCM is, for the first time, linked to global precipitation variability, providing a novel geophysical interpretation. These findings enhance our understanding of climate-driven geophysical mass redistribution and offer new insights into the processes governing seasonal GCM variations.