The Northern Chile forearc constrained by 15 years of permanent seismic monitoring

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F67985530%3A_____%2F23%3A00572098" target="_blank" >RIV/67985530:_____/23:00572098 - isvavai.cz</a>

Result on the web

<a href="https://www.sciencedirect.com/science/article/pii/S0895981123001372" target="_blank" >https://www.sciencedirect.com/science/article/pii/S0895981123001372</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.jsames.2023.104326" target="_blank" >10.1016/j.jsames.2023.104326</a>

Result language

angličtina

Original language name

The Northern Chile forearc constrained by 15 years of permanent seismic monitoring

Original language description

In this review article, we compile seismological observations from the different constituent parts of the Northern Chile forearc: the downgoing Nazca Plate, the plate interface, the upper South American Plate as well as the mantle wedge beneath it. As Northern Chile has been monitored by a network of permanent seismic stations since late 2006, there is a wealth of observations that enables us to characterize the structure as well as ongoing processes in the forearc throughout the last 15 years. We put an emphasis on the analysis of seismicity, for which we have extended a massive earthquake catalog that now contains >180,000 events for the years 2007–2021. Moreover, we draw on published results for earthquake mechanisms, source properties, seismic velocity structure, statistical seismology and others, and discuss them in context of results from neighboring disciplines. We thus attempt to provide a comprehensive overview on the seismological knowledge about the structure and ongoing processes in the Northern Chile forearc, a breviary of which is found in the following: The Northern Chile megathrust hosted two major earthquake sequences during the analyzed time period. The 2007 Mw 7.8 Tocopilla earthquake broke the deep part of the megathrust just north of Mejillones Peninsula, whereas the 2014 Mw 8.1 Iquique earthquake ruptured the central segment in the north of the study region. The latter event has a highly interesting preparatory phase, including a significant foreshock sequence as well as aseismic slip transients. Besides these large events, background seismicity elsewhere on the megathrust may be helpful for characterizing the earthquake potential and locking state in the remaining seismic gap. The downgoing Nazca Plate in Northern Chile exhibits very high seismicity rates, with the vast majority of earthquakes occurring at depths of ∼80-140 km with downdip extensive mechanisms. While seismic tomography shows no sudden changes in slab geometry along strike, seismicity describes peculiar offsets that may be linked to subducted features on the oceanic plate. Upper plate seismicity likewise shows strong variations along strike, with the north and south of the study area showing only weak activity, whereas the central segment shows pervasive microseismicity throughout the upper plate, all the way to the plate interface. These earthquakes have thrust and strike-slip mechanisms with P-axes striking roughly N-S, indicating margin-parallel compression that may be connected to the concavity of the margin.

Czech name

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Czech description

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Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

—

OECD FORD branch

10507 - Volcanology

Project

—

Continuities

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Publication year

2023

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

Journal of South American Earth Sciences

ISSN

0895-9811

e-ISSN

1873-0647

Volume of the periodical

126

Issue of the periodical within the volume

June

Country of publishing house

GB - UNITED KINGDOM

Number of pages

41

Pages from-to

104326

UT code for WoS article

001056472000001

EID of the result in the Scopus database

2-s2.0-85152667529