Russian Journal of Earth Sciences Russian Journal of Earth Sciences Russian Journal of Earth Sciences 1681-1208 103824 10.2205/2026es001091 nmracj ОРИГИНАЛЬНЫЕ СТАТЬИ ORIGINAL ARTICLES ОРИГИНАЛЬНЫЕ СТАТЬИ Analysis of Crustal Deformations Associated with Major Chilean Earthquakes of the Early 21st Century Using GNSS Observations Analysis of Crustal Deformations Associated with Major Chilean Earthquakes of the Early 21st Century Using GNSS Observations https://orcid.org/0009-0004-6479-5356 Щевьева Надежда Сергеевна Shcheveva Nadezhda Sergeevma nadezda.shchevyeva@yandex.ru https://orcid.org/0000-0002-7301-7183 Владимирова Ирина Сергеевна Vladimirova Irina Sergeevna vladimirova.is@ocean.ru

кандидат физико-математических наук;

candidate of physical and mathematical sciences;

 Институт океанологии им. П.П. Ширшова РАН Москва Россия Shirshov Institute of Oceanology, Russian academy of Sciences Moscow Russian Federation Институт теории прогноза землетрясений и математической геофизики Российской академии наук Москва Россия Institute of Earthquake Prediction Theory and Mathematical Geophysics Russian academy of sciences Moscow Russian Federation Институт океанологии им. П.П. Ширшова РАН Москва Россия Shirshov Institute of Oceanology, Russian Academy of Sciences Moscow Russian Federation 05 08 2026 05 08 2026 26 3 ES3007 02 09 2025 25 11 2025 https://www.rjes.ru/en/nauka/article/103824/view

This study presents an analysis of the surface deformations along the Chilean coastline before and after a series of major earthquakes in the early 21st century. The planar strain-rate field was computed using Shen’s method applied to continuous GNSS observations from Chile and Argentina. Results reveal an increase in strain rates proximal to the earthquake sources during the preseismic period. Conversely, the postseismic period is characterized by a reduction in strain rates in the immediate vicinity of the rupture zones, indicative of progressive relaxation of accumulated crustal stresses. The earthquake sources are localized near regions exhibiting pronounced gradients in deformation-related field parameters, underscoring their association with zones of significant stress accumulation and redistribution within the crust.

This study presents an analysis of the surface deformations along the Chilean coastline before and after a series of major earthquakes in the early 21st century. The planar strain-rate field was computed using Shen’s method applied to continuous GNSS observations from Chile and Argentina. Results reveal an increase in strain rates proximal to the earthquake sources during the preseismic period. Conversely, the postseismic period is characterized by a reduction in strain rates in the immediate vicinity of the rupture zones, indicative of progressive relaxation of accumulated crustal stresses. The earthquake sources are localized near regions exhibiting pronounced gradients in deformation-related field parameters, underscoring their association with zones of significant stress accumulation and redistribution within the crust.

 Peru–Chile subduction zone major earthquakes surface deformations satellite geodesy Shen method regional faults Peru–Chile subduction zone major earthquakes surface deformations satellite geodesy Shen method regional faults This research was carried out under the state assignment of the Ministry of Science and Higher Education of the Russian Federation for the IO RAS (theme No. FMWE2024-0018) and for the IETP RAS (No. 075-00603-25-00). This research was carried out under the state assignment of the Ministry of Science and Higher Education of the Russian Federation for the IO RAS (theme No. FMWE2024-0018) and for the IETP RAS (No. 075-00603-25-00).

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