气候变化领域集成服务门户(CCPortal): Complex co- and postseismic faulting of the 2017–2018 seismic sequence in western Iran revealed by InSAR and seismic data

CCPortal

DOI	10.1016/j.rse.2020.112224
	Complex co- and postseismic faulting of the 2017–2018 seismic sequence in western Iran revealed by InSAR and seismic data
	Fathian A.; Atzori S.; Nazari H.; Reicherter K.; Salvi S.; Svigkas N.; Tatar M.; Tolomei C.; Yaminifard F.
发表日期	2021
ISSN	00344257
卷号	253
英文摘要	The largest earthquake in the Zagros Mountains struck the city of Azgeleh on the Iran–Iraq border on 12 November 2017. This Mw 7.3 earthquake was followed by an intense seismic sequence. Implementing the double-difference earthquake location technique, we relocate 1069 events recorded by our local seismic network, deployed after the mainshock. The spatial distribution of the epicenters indicates linear alignments of the events nucleated along at least four notable clusters. The clusters are characterized by at least one significant earthquake, such as the Tazehabad earthquake of 25 August 2018 (Mw 5.9) along a dense, east–west trending cluster and the Sarpol-e Zahab earthquake of 25 November 2018 (Mw 6.3) along the cluster with a northeast–southwest trend. We use two-pass differential SAR interferometry (DInSAR) and Small BAseline Subset (SBAS) methods to study the coseismic permanent displacements of the Azgeleh, Tazehabad and Sarpol-e Zahab events as well as the one-year postseismic deformation field of the 2017–2018 seismic sequence, respectively. We use non-linear and linear optimization algorithms to derive the source geometry and the slip distribution along the fault planes. The inversion is conducted by introducing also seismological constraints, leading to the definition of a listric geometry for the Azgeleh mainshock rupture that accommodates the slip area at depth of 10–16 km along a sub-horizontal plane (dipping ~3°) and a low-angle (~16°) ramp. The thrust and dextral movements along this NNW-striking (~345°) fault have triggered a tear fault responsible for the Tazehabad event ruptured an east–west trending (~267°), north-dipping (~78°) sinistral shear fault. We present the dextral slip distribution of the Sarpol-e Zahab event along a NE-striking (~34°) fault, as a synthetic Riedel structure for the southern segment of the Khanaqin fault, dipping 63° to the southeast. We find the postseismic deformation field associated with the seismic sequence is not confined only to the mainshock source (the Azgeleh fault), but also develops along the Tazehabad and Sarpol-e Zahab faults. We additionally propose afterslip along a duplex, flat-ramp-flat structure down-dip and up-dip of the Azgeleh coseismic slip area. The up-dip afterslip develops onto the shallow detachment (~3°) at depth of ~8 km and the down-dip afterslip propagate onto the mid-crustal décollement level within the Pan-African basement. The Azgeleh, Tazehabad, Sarpol-e Zahab and Khanaqin faults mark the Lurestan Arc–Kirkuk Embayment sharp margin in the Northwest Zagros and play a key role in the lateral escape of the Lurestan Salient and vertical strain partitioning in the Zagros front. © 2020 Elsevier Inc.
语种	英语
scopus关键词	Deformation; Fault slips; Linear programming; Structural geology; Synthetic aperture radar; Co-seismic permanent displacements; Differential SAR interferometry; Double differences; Earthquake location; Linear optimization; Postseismic deformation; Seismological constraints; Small baseline subsets; Earthquakes; faulting; interferometry; optimization; rupture; seismic data; slip; spatial distribution; strain partitioning; trend analysis; Iran; Lorestan; Zagros
来源期刊	Remote Sensing of Environment
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/179010
作者单位	Neotectonics and Natural Hazards Institute, RWTH Aachen University, Aachen, Germany; Istituto Nazionale di Geofisica e Vulcanologia (INGV), Rome, Italy; Research Institute for Earth Sciences (RIES), Geological Survey of Iran (GSI), Tehran, Iran; International Institute of Earthquake Engineering and Seismology (IIEES), Tehran, Iran
推荐引用方式 GB/T 7714	Fathian A.,Atzori S.,Nazari H.,等. Complex co- and postseismic faulting of the 2017–2018 seismic sequence in western Iran revealed by InSAR and seismic data[J],2021,253.
APA	Fathian A..,Atzori S..,Nazari H..,Reicherter K..,Salvi S..,...&Yaminifard F..(2021).Complex co- and postseismic faulting of the 2017–2018 seismic sequence in western Iran revealed by InSAR and seismic data.Remote Sensing of Environment,253.
MLA	Fathian A.,et al."Complex co- and postseismic faulting of the 2017–2018 seismic sequence in western Iran revealed by InSAR and seismic data".Remote Sensing of Environment 253(2021).