气候变化领域集成服务门户(CCPortal): Active Faulting, Submarine Surface Rupture, and Seismic Migration Along the Liquiñe-Ofqui Fault System, Patagonian Andes

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DOI	10.1029/2020JB019946
	Active Faulting, Submarine Surface Rupture, and Seismic Migration Along the Liquiñe-Ofqui Fault System, Patagonian Andes
	Villalobos A.; Easton G.; Maksymowicz A.; Ruiz S.; Lastras G.; De Pascale G.P.; Agurto-Detzel H.
发表日期	2020
ISSN	21699313
卷号	125 期号:9
英文摘要	The intra-arc Liquiñe-Ofqui Fault System (LOFS) is an active transpressive fault zone located in the Patagonian Andes of Chile. In 2007, a seismic sequence occurred in the Aysén Fjord region of Chilean Patagonia along the LOFS, with a Mw 6.2 main earthquake that triggered dozens of landslides, some of which induced tsunami waves that caused severe damage and casualties. Through the analysis of high-resolution seismic reflection and bathymetric data, we identify six submarine faults cutting the Late Quaternary postglacial sedimentary infill of the fjord. The most conspicuous are the dextral-normal NE-SW striking Quitralco fault (QF) and the N-S striking strike-slip Río Cuervo (RCF) and Punta Cola faults (PCF). Our paleoseismological analysis reveals at least seven paleolandslide events buried in the fjord sediments that were triggered by local paleoearthquakes, which occurred since local ice sheet retreat, that is, circa 12 kyr. By combining tectonic observations with local seismicity data, we propose a seismotectonic model for the evolution of the 2007 seismic sequence where three structures were progressively activated from the depth toward the upper continental crust, causing surface rupture along the PCF and with earthquakes, suggesting only partial ruptures along other faults. Because the other faults did not rupture to the seafloor they remain important sources of seismic hazard. Thus, the last seismic sequence was a consequence of a stress transfer from the lower-ductile toward the upper-brittle continental crust, close to the triple junction of the Nazca, South American, and Antarctica Plates. Our results emphasize on the potential synergies between multiple geological and geophysical methods to assess complex events. © 2020. American Geophysical Union. All Rights Reserved.
英文关键词	active faults; Aysén earthquake; Liquiñe-Ofqui Fault System; paleoearthquakes; Patagonian Andes; seismic sequence
语种	英语
来源期刊	Journal of Geophysical Research: Solid Earth
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/187611
作者单位	Departamento de Geología, Facultad de Ciencias Físicas y Matemáticas, Universidad de Chile, Santiago, Chile; Departamento de Geofísica, Facultad de Ciencias Físicas y Matemáticas, Universidad de Chile, Santiago, Chile; Grup de Recerca Consolidat en Geociències Marines, Universitat de Barcelona, Barcelona, Spain; Université Côte d'Azur, IRD, CNRS, Observatoire de la Côte d'Azur, Géoazur, Nice, France
推荐引用方式 GB/T 7714	Villalobos A.,Easton G.,Maksymowicz A.,et al. Active Faulting, Submarine Surface Rupture, and Seismic Migration Along the Liquiñe-Ofqui Fault System, Patagonian Andes[J],2020,125(9).
APA	Villalobos A..,Easton G..,Maksymowicz A..,Ruiz S..,Lastras G..,...&Agurto-Detzel H..(2020).Active Faulting, Submarine Surface Rupture, and Seismic Migration Along the Liquiñe-Ofqui Fault System, Patagonian Andes.Journal of Geophysical Research: Solid Earth,125(9).
MLA	Villalobos A.,et al."Active Faulting, Submarine Surface Rupture, and Seismic Migration Along the Liquiñe-Ofqui Fault System, Patagonian Andes".Journal of Geophysical Research: Solid Earth 125.9(2020).