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Planet imagery of the 4 November 2025 landslide at Mae Moh Mine in Thailand

EOS - Thu, 11/20/2025 - 08:11

Planet imagery shows the massive coal waste landslide at Mae Moh Mine. The failure was about 4.8 km long and 1.4 km wide

As I noted in an earlier post on this blog, 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. News reports have indicated that this failure, which occurred in a slope formed from coal waste material, caused significant damage.

Unfortunately, this area is very often cloudy, so obtaining good satellite imagery is a challenge. However, Planet captured an image on 15 November 2025 that shows a substantial part of the landslide.

The image below was captured on 28 October 2025, showing the site:-

The site of the 4 November 2025 landslide at Mae Moh Mine in Thailand. Image copyright Planet, captured on 28 October 2025, used with permission.

This image shows the aftermath of the landslide:-

The aftermath of the 4 November 2025 landslide at Mae Moh Mine in Thailand. Image copyright Planet, captured on 15 November 2025, used with permission.

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

Images copyright Planet

The crown of the landslide is to the west, with movement in an eastward direction. The landslide is very large – a rough estimate is 4.77 km long and 1.37 km wide. The archive of satellite image suggests that three was large-scale dumping of mine waste in the area that became the head scarp in the weeks ahead of the landslide. This freshly deposited material can be clearly seen in the pre-failure material, and is also discernible, after the failure. The presence of this material is a good starting point in terms of understanding the causes.

Cleaning up this site is going to be a very major, and very expensive, task.

Reference

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

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A New 3-D P-wave Velocity Model for Central America using the TeletomoDD Method

Geophysical Journal International - Thu, 11/20/2025 - 00:00

SummaryCentral America’s tectonic complexity arises from the interaction of multiple plates and diverse plate boundaries, resulting in high seismic activity and intricate subduction processes. Three-dimensional seismic velocity models can provide critical constraints on subduction processes and associated earthquake hazard models. Although regional tomographic studies have offered insights into seismic activity and lithospheric processes in Central America, there have been few studies that image the entire region in a consistent manner, likely due to the geological complexity and numerical challenges. In this study, we develop a new high-resolution three-dimensional (3-D) compressional (P)-wave velocity model to investigate the subduction dynamics of the region. We apply the teletomoDD method, which uses both local and global body-wave arrivals to resolve velocity structures. We use the International Seismological Center’s EHB catalog to extract data from 6,026 regional earthquakes from 1965 to 2019, recorded by seismic stations both inside and outside of our study area. Our model is further constrained by incorporating about 30,000 global events recorded by the seismic stations within our study area. We perform both checkerboard and restoration tests to assess the resolution of the model and find that the main features are resolved robustly regardless of the initial models. The model shows a coherent high-velocity anomalies along the Middle America Trench at 50 km depth, suggesting cold, dense subducting slabs. It also captures notable variations in slab geometry, including a slab window in the southern Cocos region starting at ∼75 km depth. Low-velocity anomalies beneath major volcanic systems such as the Central American Volcanic Arc and the Trans-Mexican Volcanic Belt point to slab dehydration, fluid migration, and partial melting processes, whereas the discontinuous distribution of volcanism in Mexico and Central America appears to be influenced by the subduction of the Cocos Plate. Additionally, we identify high-velocity anomalies near the Siqueiros and Clipperton Transform Faults on the East Pacific Rise, possibly caused by mafic magmatic cumulates. The high-velocity anomaly near Swan Islands Transform Fault may reflect locally increased density inferred from previous gravity studies. Our new velocity model offers a consistent seismic structural foundation for further investigations into seismogenic processes, slab geodynamics, petrology, and rheology in Central America.

Synthetic evaluation of two semi-airborne transient electromagnetic (TEM) systems utilizing inductive and galvanic sources in hydrogeological settings

Geophysical Journal International - Thu, 11/20/2025 - 00:00

SummaryRecently, semi-airborne transient electromagnetic (TEM) systems have gained attention in geophysical investigations due to their ability for fast mapping and minimal ground access requirement. These systems consist of a ground-based transmitter source and an inductive receiver coil, carried by an uncrewed aerial vehicle. This study investigates how transmitter source selection in field-based semi-airborne TEM systems affects model parameter uncertainty, using synthetic subsurface models. The simulated dB/dt responses highlight distinct signal characteristics between the galvanic-based system (herein galvanic source) and the inductive-based system (herein inductive source), with differences observed across varying subsurface conditions. An analysis of four synthetic 3-layer models highlights that the inductive-based system resolves shallow conductors better at short offsets, whereas the galvanic-based system is better at resolving parameters for deeper targets at large offsets. Both systems, however, face challenges in accurately resolving resistive targets embedded between conductors, highlighting the need for strategic selection of the transmitter source. The galvanic-based system consistently achieves a higher signal-to-noise ratio (SNR), particularly at large offsets, making it better suited for deep exploration. In contrast, the inductive-based system exhibits lower SNR, higher noise susceptibility, and sign-changing dB/dt responses at increasing offsets adding complexity to data processing and interpretation. Despite these limitations, inductive-based systems enable earlier time measurements with signal magnitudes at short offsets comparable to galvanic-based, due to shorter current turn-off times. In this analysis we have used two system setups utilizing inductive and galvanic sources that reflect commonly used systems, but obviously, assumptions regarding transmitter characteristics such as type, size, waveform, and current amplitude, will influence the results when examining details more closely.

Soil carbon decomposition varies vastly, holding implications for climate models

Phys.org: Earth science - Wed, 11/19/2025 - 21:38

Soil stores more carbon than Earth's atmosphere and plants combined, which makes the speed of soil carbon's decomposition an important variable in models used to predict changes to our climate.

Ancient bog growth reveals shifting Southern Hemisphere winds 15,000 years ago

Phys.org: Earth science - Wed, 11/19/2025 - 20:47

Scientists have revealed that ancient bogs in the Southern Hemisphere hold clues to a major shift in Earth's climate thousands of years ago.

Complex Plumbing Dynamics for Kīlauea Volcano 

EOS - Wed, 11/19/2025 - 19:23

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

The Hawaiian Islands formed through the Pacific plate’s movement over a relatively stationary, hot mantle plume, creating a succession of progressively older volcanic centers. New land continues forming on the Big Island’s south side, where the Kīlauea volcano system has remained active for decades. After nearly 40 years of spectacular surface flows entering the sea at Pu’u’ō’ō, volcanic activity shifted to the summit caldera.

Wu et al. [2025] employ seismological techniques to analyze subtle changes in shallow crustal velocities from 2013 to 2018, combining these data with geodetic and geological observations to better understand magma reservoir interactions between Kīlauea’s caldera and Pu’u’ō’ō. Their analysis reveals a fascinating sequence of cross-communication involving pressurization and magma transport processes affected by earthquake valving. When integrated with other monitoring and modeling, such research provides valuable insights into Kīlauea’s plumbing and basaltic volcanic systems more broadly. The work also reemphasizes the importance of seismological monitoring, and deployment of dense seismic networks at as many active volcanoes as possible would enable new comparative analyses.

Citation: Wu, S.-M., Lin, G., & Shearer, P. (2025). Seismic velocity monitoring reveals complex magma transport dynamics at Kīlauea Volcano prior to the 2018 eruption. AGU Advances, 6, e2025AV001759. https://doi.org/10.1029/2025AV001759

—Thorsten Becker, Editor, AGU Advances

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.