{"title":"Decadal change of seismic structure in the Earth's lowermost mantle.","authors":"Xin Zhang, Lianxing Wen","doi":"10.1038/s41467-025-63814-3","DOIUrl":null,"url":null,"abstract":"<p><p>Studying temporal changes of seismic property could provide a direct mean to monitor dynamic processes in the Earth's lowermost mantle, yet no related seismic observations were discovered. Here, we report temporal changes of seismic data between a pair of nearly co-located earthquakes occurring on 2000/07/07 and 2009/12/17 and infer two types of decadal-scale structural changes in the lowermost mantle: (1) a 10s km-scale shrinkage or movement of an ultra-low velocity zone near the core-mantle boundary, and (2) opposing shear wave anisotropy changes in the top and bottom portions of the lowermost ~300 km mantle. These findings suggest that ultra-low velocity zones are deformed as partially molten materials or moved by vigorous localized material flows and the region of the lowermost mantle possesses a separate layer circulation. This report demonstrates the capability of seismic monitoring of deep mantle dynamics and calls for new geodynamical models to account for these previously unrecognized features.</p>","PeriodicalId":19066,"journal":{"name":"Nature Communications","volume":"16 1","pages":"8754"},"PeriodicalIF":15.7000,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Nature Communications","FirstCategoryId":"103","ListUrlMain":"https://doi.org/10.1038/s41467-025-63814-3","RegionNum":1,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"MULTIDISCIPLINARY SCIENCES","Score":null,"Total":0}
引用次数: 0
Abstract
Studying temporal changes of seismic property could provide a direct mean to monitor dynamic processes in the Earth's lowermost mantle, yet no related seismic observations were discovered. Here, we report temporal changes of seismic data between a pair of nearly co-located earthquakes occurring on 2000/07/07 and 2009/12/17 and infer two types of decadal-scale structural changes in the lowermost mantle: (1) a 10s km-scale shrinkage or movement of an ultra-low velocity zone near the core-mantle boundary, and (2) opposing shear wave anisotropy changes in the top and bottom portions of the lowermost ~300 km mantle. These findings suggest that ultra-low velocity zones are deformed as partially molten materials or moved by vigorous localized material flows and the region of the lowermost mantle possesses a separate layer circulation. This report demonstrates the capability of seismic monitoring of deep mantle dynamics and calls for new geodynamical models to account for these previously unrecognized features.
期刊介绍:
Nature Communications, an open-access journal, publishes high-quality research spanning all areas of the natural sciences. Papers featured in the journal showcase significant advances relevant to specialists in each respective field. With a 2-year impact factor of 16.6 (2022) and a median time of 8 days from submission to the first editorial decision, Nature Communications is committed to rapid dissemination of research findings. As a multidisciplinary journal, it welcomes contributions from biological, health, physical, chemical, Earth, social, mathematical, applied, and engineering sciences, aiming to highlight important breakthroughs within each domain.