气候变化领域集成服务门户(CCPortal): Geodetic Observations of Shallow Creep on the Laohushan-Haiyuan Fault, Northeastern Tibet

CCPortal

DOI	10.1029/2020JB021576
	Geodetic Observations of Shallow Creep on the Laohushan-Haiyuan Fault, Northeastern Tibet
	Li Y.; Nocquet J.-M.; Shan X.; Song X.
发表日期	2021
ISSN	21699313
卷号	126 期号:6
英文摘要	We investigated the spatial distribution of aseismic creep on the Laohushan-Haiyuan fault using Global Positioning System (GPS) data (1999–2017) and Interferometric Synthetic Aperture Radar (InSAR) data (2003–2010). Comparisons among GPS, InSAR line-of-sight (LOS) rates, and leveling show that neither leveling nor GPS vertical velocities can fit the vertical signal mapped into the LOS, implying either complicated vertical crustal deformation in northeastern Tibet and/or complex error structures in the InSAR data. Thus, we combined horizontal GPS with high-pass filtered InSAR data to produce a continuous LOS rate map crossing the fault. Our geodetic data reveal three creep sections along the fault. Both the restored LOS data and decomposed ascending and descending InSAR data highlight the fact that vertical motion can cause an overestimation of creep rate; we obtained a refined creep rate of 2.5 ± 0.4 mm/a on the Laohushan fault. We further identified a 10 km-long, ∼3–5 mm/a creep section (∼104.2°E−104.3°E) and a 43 km-long, ∼1–3 mm/a creep section (∼105.3°E−105.7°E) on the western and eastern Haiyuan fault respectively. Both are located on fault sections that ruptured during the 1920 M∼8 earthquake, suggesting that the 1920 earthquake was able to cross pre-existing creep sections or that the fault shows heterogeneous relocking after large earthquakes, with creep lasting decades on some parts of the rupture. Fault coupling shows a highly variable rate of slip deficit accumulation along strike, suggesting that coupling might significantly evolve during the period between two large earthquakes. © 2021. American Geophysical Union. All Rights Reserved.
英文关键词	aseismic creep; earthquake potential; fault coupling; GPS and InSAR; Haiyuan fault
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/187060
作者单位	State Key Laboratory of Earthquake Dynamics, Institute of Geology, China Earthquake Administration, Beijing, China; Université Côte d'Azur, Geoazur, IRD, CNRS, Observatoire de la Côte d'Azur, Valbonne, France; Université de Paris, Institut de Physique du Globe de Paris, Paris, France
推荐引用方式 GB/T 7714	Li Y.,Nocquet J.-M.,Shan X.,et al. Geodetic Observations of Shallow Creep on the Laohushan-Haiyuan Fault, Northeastern Tibet[J],2021,126(6).
APA	Li Y.,Nocquet J.-M.,Shan X.,&Song X..(2021).Geodetic Observations of Shallow Creep on the Laohushan-Haiyuan Fault, Northeastern Tibet.Journal of Geophysical Research: Solid Earth,126(6).
MLA	Li Y.,et al."Geodetic Observations of Shallow Creep on the Laohushan-Haiyuan Fault, Northeastern Tibet".Journal of Geophysical Research: Solid Earth 126.6(2021).