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A new study has challenged the long-standing assumption that global warming will inevitably turn humid subtropical forests into carbon sources, revealing these ecosystems may instead continue accumulating soil carbon under moderate temperature rises. The study was published in One Earth on Oct. 6.

Magnetotelluric (MT) data, which contain measurements of electric and magnetic field variations at Earth's surface, provide insights into the electrical resistivity of Earth's crust and upper mantle. Changes in resistivity, or the ability to conduct an electrical current, can indicate the presence of geologic features such as igneous intrusions or sedimentary basins, meaning MT surveys can complement other kinds of geophysical surveys to help reveal Earth's subsurface. In addition, such surveys can play an important role in improving understanding of the risks space weather poses to human infrastructure.

How do volcanoes work? What happens beneath their surface? What causes the vibrations—known as tremor—that occur when magma or gases move upward through a volcano's conduits? Professor Dr. Miriam Christina Reiss, a volcano seismologist at Johannes Gutenberg University Mainz (JGU), and her team have located such tremor signals at the Oldoinyo Lengai volcano in Tanzania.

According to a study by the Department of Physics and the Institute of Environmental Science and Technology of the Universitat Autònoma de Barcelona (ICTA-UAB), the Mar Menor saltwater lagoon in Murcia, Spain, the largest in Europe, contains sediments with levels of lead, arsenic, zinc, mercury, copper, and silver that exceed toxicity thresholds and values reported for similar coastal ecosystems worldwide. The findings are published in the journal Marine Pollution Bulletin.

Heat waves in the UK have led to unseasonable drying of vegetation bypassing natural ecological processes that limit the spread of wildfires, a new study has found.

Greenland is melting, the Alps are melting and the Himalayas are melting—yet in one vast mountain region, huge glaciers have remained stable, or even gained mass, in recent decades. Can it last?

A new fossil fuel site approved for development off Western Australia's coast is estimated to contribute 876 million tons of carbon dioxide (CO2) emissions over the course of its lifetime, according to new research led by The Australian National University (ANU) in collaboration with the ARC Center of Excellence for the Weather of the 21st century.

Reconstruction of landslides on the banks of Lake Rupanco in Chile, triggered by the 22 May 1960 Mw-9.5 earthquake, suggests that a slope failure with a volume of 161 million cubic metres triggered a tsunami with a maximum amplitude of 33.3 metres. About 120 people were killed.

A very interesting paper (Quiroga et al. 2025) has just been published in the journal Landslides that examines combined landslide – tsunami threats at Lake Rupanco [40.82, -72.50] in Chile. The context is a series of landslides, and a resultant tsunami, that was triggered by the 22 May 1960 Mw=9.5 Great Chilean earthquake. The paper reconstructs that landslides and models the tsunami that they generated.

This event is particularly interesting as the loss of life was significant. Quiroga et al. (2025) document about 120 fatalities:-

“The most severely impacted area was Las Gaviotas, a settlement situated on the southeast shore…, where tsunami run-up heights reportedly exceeded 10 m, according to eyewitness accounts… One of the most significant losses was the destruction of the popular Termas de Rupanco hotel located near geothermal springs …, which was swept away by the landslides, resulting in 11 confirmed fatalities … At that time, a road was also under construction along the southern shoreline to connect Osorno with Las Gaviotas; both the road and several worker camps were destroyed…”

The Chilean Enterreno site has a photograph of the Termas de Rupanco hotel prior to the tsunami:-

Hotel Termas de Rupanco, which was destroyed by the landslide-induced tsunami 1960. Image from Enterreno. Posted by Francisco Vidal Guzmán under a by-nc licence.

Quiroga et al. (2025) have tracked the source of the tsunami to a series of landslides that occurred on the north side of Lake Rupanco. The scars of these failures are still very visible on Google Earth:-

Google Earth image of the site of the landslides on the banks of Lake Rupanco triggered by the 22 May 1960 earthquake in Chile.

Quiroga et al. (2025) have identified eight landslide scars in this area, of which the most significant is the bowl-shaped scar in the centre of the image above. This is the most likely source of the tsunami. It is a rotational failure with lower runout zone, with a volume of 161 million m3. Of this volume, 12.1 million m3 became submerged to generate the wave.

Reconstruction of the wave suggests that it has a maximum amplitude of 33.3 metres close to the landslide itself. At Las Gaviotas, where the hotel was located, the wave had a maximum amplitude of 8.6 metres, arriving 261 seconds after initiation.

This elegant and useful paper illustrates well the threat posed by large landslides into lakes. For those located in the hotel, the events would have been terrifying, starting with a major earthquake for which the shaking would have been intense and long-lasting, followed by the noise and dust generated by the collapsing slopes, and finally the impact of this enormous tsunami. Keeping people safe in such circumstances is a very major challenge.

Reference

Quiroga, J.P., Aránguiz, R., Hernández-Madrigal, V.M. et al. 2025. Reconstruction and numerical modeling of historical and paleo-tsunamigenic landslides in Lake Rupanco, Chile. Landslides. https://doi.org/10.1007/s10346-025-02629-1.

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.

The world faces a "new reality" as we have reached the first of many Earth system tipping points that will cause catastrophic harm unless humanity takes urgent action, according to a report released by the University of Exeter and international partners.

SummaryA growing body of literature has contributed to linking the presence of bacteria with SIP signals. Yet, there are still unresolved questions concerning the contribution of cell density and microbial metabolic activity in porous media (soils and sediments) to SIP signals. Moreover, there is continued debate on whether cells themselves polarize or whether a cell-sediment interaction is a prerequisite for the measured responses. This study investigates the SIP response of Shewanella oneidensis MR-1 in isolation, that is, in the absence of a mineral porous medium using two setups (i) cells in aqueous suspension and (ii) alginate bead-packed reactors. Results from experiments conducted with static cell suspensions shed light on the strong control of cell settling that drives erratic, poorly reproducible and difficult to interpret SIP signals. However, incubating cells in bead packed reactors yielded reproducible trends in σ″, with strong (3 – 10 mrad) signals that followed the expected cell growth behaviour. Relating σ″ to measured cell density and metabolic activity (using ATP) highlighted the strongly linked contribution of both activity and cell density and SIP. Here, we report a lower frequency polarization peak between 0.01 and 0.1 Hz in the bead reactors, which we attribute to the polarization of cell colonies in the densely packed reactors. In summary, our findings shed light on the direct contribution of cells and their activity to polarization, in the absence of cell-sediment interactions and provide a novel approach for studying cell polarization in static incubation in a porous environment.

SummaryWe present DASPack, a high-performance, open-source compression tool specifically designed for distributed acoustic sensing (DAS) data. As DAS becomes a key technology for real-time, high-density, and long-range monitoring in fields such as geophysics, infrastructure surveillance, and environmental sensing, the volume of collected data is rapidly increasing. Large-scale DAS deployments already generate hundreds of terabytes and are expected to increase in the coming years, making long-term storage a major challenge. Despite this urgent need, few compression methods have proven to be both practical and scalable in real-world scenarios. DASPack is a fully operational solution that consistently outperforms existing techniques for DAS data. It enables both controlled lossy and lossless compression by allowing users to choose the maximum absolute difference per datum between the original and compressed data. The compression pipeline combines wavelet transforms, linear predictive coding, and entropy coding to optimise efficiency. Our method achieves up to 3 × file size reductions for strain and strain rate data in lossless mode across diverse datasets. In lossy mode, compression improves to 6 × with near-perfect signal fidelity, and up to 10 × is reached with acceptable signal degradation. It delivers fast throughput (100–200 MB s−1 using a single-thread and up to 750 MB s−1 using 8-threads), enabling real-time deployment even under high data rates. We validated its performance on 15 datasets from a variety of acquisition environments, demonstrating its speed, robustness, and broad applicability. DASPack provides a practical foundation for long-term, sustainable DAS data management in large-scale monitoring networks.

The timing of emissions reductions, even more so than the rate of reduction, will be key to avoiding catastrophic thresholds for ice-melt and sea-level rise, according to a new Cornell University study.

Glaciers are fighting back against climate change by cooling the air that touches their surfaces. But for how long? The Pellicciotti group at the Institute of Science and Technology Austria (ISTA) has compiled and re-analyzed an unprecedented dataset of on-glacier observations worldwide. Their findings, published today in Nature Climate Change, demonstrate that glaciers will likely reach the peak of their self-cooling power by the next decade before their near-surface temperatures spike up and melting accelerates.

Guided by the rhythms of the sea and the promise of discovery, Teledyne Marine and Rutgers University will set Redwing, an autonomous underwater vehicle, on its journey on Friday, Oct. 10, leading to its launch into the Atlantic Ocean off the coast of Martha's Vineyard in Massachusetts.

New research from the University of St Andrews has shed light on a crucial mechanism of lowering atmospheric CO2 during Earth's past ice ages.

Tiny crystals in Earth’s crust may have recorded meteorite and comet impacts as our planet traveled through the spiral arms of the Milky Way over more than 4 billion years, according to new research.

The study is one of the first to suggest that galactic-scale processes can affect Earth’s geology, and researchers think similar evidence might be found on other bodies in the solar system, including the Moon and Mars.

“This is something that could connect the Earth, the Moon, and Mars into the wider galactic surroundings.”

“This is so interesting and exciting—we are potentially seeing something that is not just unique to Earth,” explained geologist Chris Kirkland of Australia’s Curtin University, the first author of the new study published in Physical Review Research. “This is something that could connect the Earth, the Moon, and Mars into the wider galactic surroundings.”

Kirkland and his coauthor, University of Lincoln astrophysicist Phil Sutton, studied changes in oxygen isotopes in a database of tens of thousands of dated crystals of zircon—a silicate mineral with the chemical formula ZrSiO4 that is common in Earth’s crust. They compared their findings to maps of the Milky Way galaxy that show its neutral hydrogen, or H1.

H1, with one proton and one electron, is the most abundant element in the universe, and its density is particularly high in the arms of the Milky Way galaxy.

Because they are almost exactly the same size, uranium atoms sometimes replace the zirconium atoms in zircon. Uranium radioactively decays into lead over time, so geologists can study the levels of uranium and lead isotopes in zircon crystals to determine when the crystals formed, sometimes in the first phases of the evolution of Earth’s crust about 4.4 billion years ago.

“Zircon crystals are a geologist’s best friend…we can get a lot of information from a single zircon grain.”

“Zircon crystals are a geologist’s best friend,” Kirkland said. “They have an inbuilt clock, and they carry a chemical signature that tells us how they formed—so we can get a lot of information from a single zircon grain.”

Queen’s University geochemist Christopher Spencer, who was not involved in the study, said that the work was fascinating and provocative. “I think the study is a reminder that Earth does not evolve in isolation and that interdisciplinary thinking, however speculative at first, can open up new ways of framing questions about our planet’s history.”

Oxygen Isotope Ratios

The key to the latest research was in the ratios of isotopes—forms of the same chemical element that have different numbers of neutrons—in the oxygen atoms of zircon’s silicate group.

The relative levels of oxygen isotopes in samples of zircon crystals can tell geologists whether the crystals formed high in the crust, perhaps while interacting with water and sediments, or deeper within Earth’s mantle.

Kirkland said the latest study examined the distribution of the ratios of oxygen isotopes found in a dataset of zircon crystals sampled from around the world. The scientists evaluated the data’s “kurtosis,” or the measure of how flat or peaked a distribution is. A dataset with high kurtosis has a narrow distribution, with most values occurring in the middle and causing a sharp peak in the distribution curve. In contrast, a dataset with low kurtosis has a wide distribution with more high and low values, causing a wider distribution curve with a less pronounced peak.

The researchers determined that periods of high oxygen isotope kurtosis corresponded to times when our solar system was crossing the dense spiral arms of the Milky Way galaxy. Such crossings occurred roughly every 187 million years on average during our solar system’s 748-million-year orbit around the galactic center at a speed of about 240 kilometers per second.

In addition to H1, the spiral arms are filled with many more stars than the interstellar space between them. The gravity of those stars seems to have disturbed the Oort Cloud—the haze of billions of icy rock fragments that surrounds our solar system. That, in turn, caused more meteors and comets to strike Earth as it passed through the galactic arms, leading to the subsequent melting of the crust in many places, Kirkland said. “By looking at the variability of the [zircon] signal over time, we were able to get an indication of how different the magma production on the planet was at that time.”

Professor Chris Kirkland uses an ion microprobe to date zircon mineral grains. Credit: C. L. Kirkland

He warned that correlation does not mean causation but said that in this case there seemed to be no other plausible cause for the periodic kurtosis of the oxygen isotope ratios in zircons. “It is very important that we are able to see the frequency of [meteor and comet] impacts” on Earth, Kirkland said. “Rather than an internal process, we seem to be looking at an external process.”

Some other experts suggest the new study is notable for outlining the concept that galactic processes could have left geological traces, but it is not yet conclusive proof.

Earth scientist Craig Storey of the University of Portsmouth in the United Kingdom, who was not involved in the new study, said crustal melting did not necessarily prove an increase in meteorite or comet impacts. Instead, natural processes here on Earth, such as volcanic or tectonic movements, could have caused melting of the crust at several stages of our planet’s geological history.

He is also concerned that some of the proposed correlations in the study may not be correct. “It is an interesting idea, and there are potentially ways to test it, but I don’t think this is the way to test it,” Storey said.

—Tom Metcalfe (@HHAspasia) Science Writer

Citation: Metcalfe, T. (2025), Zircon crystals could reveal Earth’s path among the stars, Eos, 106, https://doi.org/10.1029/2025EO250379. Published on 10 October 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.

Source: Journal of Geophysical Research: Solid Earth

Magnetotelluric (MT) data, which contain measurements of electric and magnetic field variations at Earth’s surface, provide insights into the electrical resistivity of Earth’s crust and upper mantle. Changes in resistivity, or the ability to conduct an electrical current, can indicate the presence of geologic features such as igneous intrusions or sedimentary basins, meaning MT surveys can complement other kinds of geophysical surveys to help reveal Earth’s subsurface. In addition, such surveys can play an important role in improving understanding of the risks space weather poses to human infrastructure.

Montiel-Álvarez et al. present the first 3D electrical resistivity model of Britain, based on long-period MT data (using measurements gathered every second for 4–6 weeks at a time) from across the island. Their model, called BERM-2024, points to previously recognized as well as likely new tectonic and geological structures. The authors also model the effects of a recent solar storm on Earth’s geoelectric field, validating the usefulness of MT-based approaches for space weather impact forecasting.

The BERM-2024 electrical resistivity model is based on MT data from 69 sites in Britain, including both new and legacy datasets. Creating the final model involved processing the raw time series data and accounting for the “coastal effect” caused by the conductivity of ocean water when inverting the data—or calculating causes based on observations.

Sensitivity tests of the new model indicate it resolves features to depths of 200 kilometers (125 miles), including many known from other geophysical surveys and geological observations. It also reveals new anomalies, including highly conductive areas under Scotland’s Southern Uplands Terrane and a resistive anomaly under the island of Anglesey. More intriguing, a large, previously unknown conductive anomaly appears in their model between 85 and 140 kilometers (52–87 miles) beneath the West Midlands region.

The authors tested the utility of their resistivity model for estimating the electric field at Earth’s surface, which is key in forecasting the effects of geomagnetically induced currents caused by space weather. To do so, they obtained a time series of the horizontal electric field across Britain during a solar storm that occurred on 10–11 October 2024, which led to bright displays of aurora borealis across the Northern Hemisphere. They found good agreement between their modeled time series and those measured at observatories, indicating that electrical resistivity models are a tool that can provide accurate information for space weather impact planning. (Journal of Geophysical Research: Solid Earth, https://doi.org/10.1029/2025JB031813, 2025)

—Nathaniel Scharping (@nathanielscharp), Science Writer

Citation: Scharping, N. (2025), New 3D model reveals geophysical structures beneath Britain, Eos, 106, https://doi.org/10.1029/2025EO250381. Published on 10 October 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.

SummaryInitial stress exerts a crucial impact on the elastic properties and thus the wave reflection in the layered media. However, the stress effect on wave reflection characteristics in such media remain insufficiently understood. To address this issue, we develop a composite matrix reflectivity method incorporating initial overburden stress (CMRMS) by means of acoustoelasticity theory, enabling accurate modeling of seismic wave propagation in stressed layered media. The proposed method can better simulate multiple reflections, converted waves and transmission loss of seismic waves in layered media, compared to the classic stress-dependent reflection coefficient equation for a single interface. Moreover, our method can degenerate into the existing methods in the cases of no initial stress and single interface, which verifies its correctness. We further extended the CMRMS to elastic and viscoelastic non-welded interfaces using the linear-slip theory and standard linear solid model, respectively. The extended method is used to investigate the impacts of non-welded interface compliance, overburden stress, fluid viscosity and frequency on seismic reflection characteristics within layered model. It is shown that the stress effect magnitude on interface reflection significantly depends on the interface depth, due to cumulative transmission losses from overlying layers. Moreover, increasing either the compliance or the number of overlying non-welded interface significantly reduces the reflection amplitude at deeper interface. Our results show the potential of the proposed composite matrix reflectivity method to consider the joint effects of initial stress, multiple waves and transmission loss in both forward modelling and inverse applications.

Dry soils in northern Mexico may trigger episodes of simultaneous drought and heat wave hundreds of miles away in the southwestern United States, such as Arizona, New Mexico, and Texas, according to a new study. These "hot droughts" in the region increasingly persist through consecutive days and nights rather than easing up after sundown, the research also found, leaving no window for afflicted areas to recover.

An EPFL engineer has illustrated some of the complex ways in which climate change will affect hydropower facilities, taking the Gries dam in Valais Canton as a case study.