Shallow Tectonic Tremors Reveal the Beginning of the Slab Window at the Chilean Triple Junction
Abstract The subduction of active spreading centers is an unusual phenomenon along subduction zones. In southern Chile, the Nazca‐Antarctic spreading system (Chile Rise) subducts beneath the South America plate at the Chile Triple Junction (CTJ), forming the Patagonian slab window. The beginning (sp...
Saved in:
| Main Authors: | , , , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Wiley
2025-07-01
|
| Series: | Geophysical Research Letters |
| Subjects: | |
| Online Access: | https://doi.org/10.1029/2025GL115019 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1850075367800307712 |
|---|---|
| author | Kellen Azúa Satoshi Ide Seiya Yano Sergio Ruiz Hiroko Sugioka Hajime Shiobara Aki Ito Matthew Miller Hikaru Iwamori |
| author_facet | Kellen Azúa Satoshi Ide Seiya Yano Sergio Ruiz Hiroko Sugioka Hajime Shiobara Aki Ito Matthew Miller Hikaru Iwamori |
| author_sort | Kellen Azúa |
| collection | DOAJ |
| description | Abstract The subduction of active spreading centers is an unusual phenomenon along subduction zones. In southern Chile, the Nazca‐Antarctic spreading system (Chile Rise) subducts beneath the South America plate at the Chile Triple Junction (CTJ), forming the Patagonian slab window. The beginning (spatially youngest portion) of the slab window has been estimated based on plate kinematic reconstructions, but direct observations remain insufficient. To investigate this tectonic feature in detail, an Ocean Bottom Seismometer array was deployed south of the CTJ between 2019 and 2021. Using these continuous data and the envelope correlation method, we searched for tectonic tremors to complement the seismic observations and detected more than 500 events in this period. A notable separation between fast seismicity and tremors is observed at the current location of the subducted Chile Rise segment. We interpret this seismic gap as evidence of the Patagonian slab window formation within the last 0.3 Myr. |
| format | Article |
| id | doaj-art-3561fa31937f4edaa820a9062c4e427f |
| institution | DOAJ |
| issn | 0094-8276 1944-8007 |
| language | English |
| publishDate | 2025-07-01 |
| publisher | Wiley |
| record_format | Article |
| series | Geophysical Research Letters |
| spelling | doaj-art-3561fa31937f4edaa820a9062c4e427f2025-08-20T02:46:20ZengWileyGeophysical Research Letters0094-82761944-80072025-07-015214n/an/a10.1029/2025GL115019Shallow Tectonic Tremors Reveal the Beginning of the Slab Window at the Chilean Triple JunctionKellen Azúa0Satoshi Ide1Seiya Yano2Sergio Ruiz3Hiroko Sugioka4Hajime Shiobara5Aki Ito6Matthew Miller7Hikaru Iwamori8Departamento de Geofísica Universidad de Chile Santiago ChileDepartment of Earth and Planetary Science The University of Tokyo Tokyo JapanDepartment of Earth and Planetary Science The University of Tokyo Tokyo JapanDepartamento de Geofísica Universidad de Chile Santiago ChileKobe University Kobe JapanEarthquake Research Institute The University of Tokyo Tokyo JapanJapan Agency of Marine‐Earth Science and Technology Yokosuka JapanDepartamento de Geofísica Universidad de Concepción Concepción ChileEarthquake Research Institute The University of Tokyo Tokyo JapanAbstract The subduction of active spreading centers is an unusual phenomenon along subduction zones. In southern Chile, the Nazca‐Antarctic spreading system (Chile Rise) subducts beneath the South America plate at the Chile Triple Junction (CTJ), forming the Patagonian slab window. The beginning (spatially youngest portion) of the slab window has been estimated based on plate kinematic reconstructions, but direct observations remain insufficient. To investigate this tectonic feature in detail, an Ocean Bottom Seismometer array was deployed south of the CTJ between 2019 and 2021. Using these continuous data and the envelope correlation method, we searched for tectonic tremors to complement the seismic observations and detected more than 500 events in this period. A notable separation between fast seismicity and tremors is observed at the current location of the subducted Chile Rise segment. We interpret this seismic gap as evidence of the Patagonian slab window formation within the last 0.3 Myr.https://doi.org/10.1029/2025GL115019slab windowshallow tectonic tremorsmid‐ocean ridge |
| spellingShingle | Kellen Azúa Satoshi Ide Seiya Yano Sergio Ruiz Hiroko Sugioka Hajime Shiobara Aki Ito Matthew Miller Hikaru Iwamori Shallow Tectonic Tremors Reveal the Beginning of the Slab Window at the Chilean Triple Junction Geophysical Research Letters slab window shallow tectonic tremors mid‐ocean ridge |
| title | Shallow Tectonic Tremors Reveal the Beginning of the Slab Window at the Chilean Triple Junction |
| title_full | Shallow Tectonic Tremors Reveal the Beginning of the Slab Window at the Chilean Triple Junction |
| title_fullStr | Shallow Tectonic Tremors Reveal the Beginning of the Slab Window at the Chilean Triple Junction |
| title_full_unstemmed | Shallow Tectonic Tremors Reveal the Beginning of the Slab Window at the Chilean Triple Junction |
| title_short | Shallow Tectonic Tremors Reveal the Beginning of the Slab Window at the Chilean Triple Junction |
| title_sort | shallow tectonic tremors reveal the beginning of the slab window at the chilean triple junction |
| topic | slab window shallow tectonic tremors mid‐ocean ridge |
| url | https://doi.org/10.1029/2025GL115019 |
| work_keys_str_mv | AT kellenazua shallowtectonictremorsrevealthebeginningoftheslabwindowatthechileantriplejunction AT satoshiide shallowtectonictremorsrevealthebeginningoftheslabwindowatthechileantriplejunction AT seiyayano shallowtectonictremorsrevealthebeginningoftheslabwindowatthechileantriplejunction AT sergioruiz shallowtectonictremorsrevealthebeginningoftheslabwindowatthechileantriplejunction AT hirokosugioka shallowtectonictremorsrevealthebeginningoftheslabwindowatthechileantriplejunction AT hajimeshiobara shallowtectonictremorsrevealthebeginningoftheslabwindowatthechileantriplejunction AT akiito shallowtectonictremorsrevealthebeginningoftheslabwindowatthechileantriplejunction AT matthewmiller shallowtectonictremorsrevealthebeginningoftheslabwindowatthechileantriplejunction AT hikaruiwamori shallowtectonictremorsrevealthebeginningoftheslabwindowatthechileantriplejunction |