No Temporal Change Seen in High‐Frequency Waves Scattered Near the Core‐Mantle Boundary
Abstract The core‐mantle boundary (CMB) and the outermost core are dynamic and heterogeneous regions with time‐dependent flows. We examine two seismic raypaths, diffracted P and PKP precursors—both replete with scattering, with precisely repeating earthquakes. These earthquakes, occurring in the Sou...
Saved in:
| Main Authors: | , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Wiley
2024-12-01
|
| Series: | Geophysical Research Letters |
| Subjects: | |
| Online Access: | https://doi.org/10.1029/2024GL112155 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1849330337412284416 |
|---|---|
| author | Ruoyan Wang John E. Vidale Wei Wang |
| author_facet | Ruoyan Wang John E. Vidale Wei Wang |
| author_sort | Ruoyan Wang |
| collection | DOAJ |
| description | Abstract The core‐mantle boundary (CMB) and the outermost core are dynamic and heterogeneous regions with time‐dependent flows. We examine two seismic raypaths, diffracted P and PKP precursors—both replete with scattering, with precisely repeating earthquakes. These earthquakes, occurring in the South Sandwich Islands, were recorded on the Yellowknife array in Canada, the Alice Springs array in Australia, and the Eilson Array in United States for the past 30 years. In all the most resolved cases, five for diffracted P and 19 for PKP precursors, we observe 1–2 Hz scattered waves that exactly repeat within the resolution of our study for more than 10 s. Although the absence of observable changes is unsurprising, it imposes constraints on potential temporal variations near the CMB. This suggests that any dynamic processes in this region might either be too subtle to detect, even with high‐frequency waves, or occur on different timescales. |
| format | Article |
| id | doaj-art-11db5e11526f4766b4e9e46c212e828e |
| institution | Kabale University |
| issn | 0094-8276 1944-8007 |
| language | English |
| publishDate | 2024-12-01 |
| publisher | Wiley |
| record_format | Article |
| series | Geophysical Research Letters |
| spelling | doaj-art-11db5e11526f4766b4e9e46c212e828e2025-08-20T03:46:58ZengWileyGeophysical Research Letters0094-82761944-80072024-12-015123n/an/a10.1029/2024GL112155No Temporal Change Seen in High‐Frequency Waves Scattered Near the Core‐Mantle BoundaryRuoyan Wang0John E. Vidale1Wei Wang2Department of Earth Sciences University of Southern California Los Angeles CA USADepartment of Earth Sciences University of Southern California Los Angeles CA USAKey Laboratory of Earth and Planetary Physics Institute of Geology and Geophysics Chinese Academy of Sciences Beijing ChinaAbstract The core‐mantle boundary (CMB) and the outermost core are dynamic and heterogeneous regions with time‐dependent flows. We examine two seismic raypaths, diffracted P and PKP precursors—both replete with scattering, with precisely repeating earthquakes. These earthquakes, occurring in the South Sandwich Islands, were recorded on the Yellowknife array in Canada, the Alice Springs array in Australia, and the Eilson Array in United States for the past 30 years. In all the most resolved cases, five for diffracted P and 19 for PKP precursors, we observe 1–2 Hz scattered waves that exactly repeat within the resolution of our study for more than 10 s. Although the absence of observable changes is unsurprising, it imposes constraints on potential temporal variations near the CMB. This suggests that any dynamic processes in this region might either be too subtle to detect, even with high‐frequency waves, or occur on different timescales.https://doi.org/10.1029/2024GL112155seismologycoremantlebody waveseismic arrayrepeating earthquakes |
| spellingShingle | Ruoyan Wang John E. Vidale Wei Wang No Temporal Change Seen in High‐Frequency Waves Scattered Near the Core‐Mantle Boundary Geophysical Research Letters seismology core mantle body wave seismic array repeating earthquakes |
| title | No Temporal Change Seen in High‐Frequency Waves Scattered Near the Core‐Mantle Boundary |
| title_full | No Temporal Change Seen in High‐Frequency Waves Scattered Near the Core‐Mantle Boundary |
| title_fullStr | No Temporal Change Seen in High‐Frequency Waves Scattered Near the Core‐Mantle Boundary |
| title_full_unstemmed | No Temporal Change Seen in High‐Frequency Waves Scattered Near the Core‐Mantle Boundary |
| title_short | No Temporal Change Seen in High‐Frequency Waves Scattered Near the Core‐Mantle Boundary |
| title_sort | no temporal change seen in high frequency waves scattered near the core mantle boundary |
| topic | seismology core mantle body wave seismic array repeating earthquakes |
| url | https://doi.org/10.1029/2024GL112155 |
| work_keys_str_mv | AT ruoyanwang notemporalchangeseeninhighfrequencywavesscatterednearthecoremantleboundary AT johnevidale notemporalchangeseeninhighfrequencywavesscatterednearthecoremantleboundary AT weiwang notemporalchangeseeninhighfrequencywavesscatterednearthecoremantleboundary |