2022年3月、ポルトガル領アゾレス諸島のサン・ジョルジェ島直下で大規模なマグマの上昇が発生し、数千回に及ぶ地震を引き起こした末に地下で停止した。新たな研究で詳細が明らかになったこの事象は、噴火には至らなかったものの、火山活動への懸念を一時的に高め、その後沈静化した経緯を示すものとなった。
マグマは地下20キロメートル以深から発生し、わずか数日間で急速に上昇した。オリンピックサイズのプール約3万2000杯分に相当する溶岩が含まれていたが、地表から1.6キロメートルの深さで停止し、その影響で島の地表は約6センチメートル隆起した。地震の大部分はマグマの上昇が停止した後に発生し、その活動はピコ・ド・カルヴァン断層帯に集中していた。
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A 6.9 magnitude earthquake struck on Monday, May 25 at 17:52 with its epicenter 20 kilometers northeast of Calama. The quake was felt across four northern regions and caused power outages and mining halts.
Researchers have verified a rare deep earthquake that struck beneath Utah in 1979 at a depth once thought impossible for such events under continents. New analysis of old data and a 2025 quake support the existence of continental mantle earthquakes.
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Researchers have identified natural barrier zones on an underwater fault that act as brakes to stop earthquakes from growing larger. The findings come from detailed studies of the Gofar transform fault off Ecuador.
Researchers have developed a three-dimensional model showing that a broad eastward-moving mantle wind supplies magma to Yellowstone rather than a deep plume from Earth's core.
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A new study finds that tectonic stress along Southern California's San Andreas and San Jacinto faults has reached levels unseen in the past millennium. Researchers identified Cajon Pass as an earthquake gate that could allow a rupture to spread across both systems. The findings, based on a physics-based model, highlight conditions that historically preceded major multi-fault events.
Scientists have captured the first clear images of a subduction zone breaking apart beneath the Pacific Northwest. The Juan de Fuca plate is splitting into fragments as it sinks under the North American plate. The findings, from a 2021 seismic experiment, reveal a gradual tearing process.