Rapid Near-Field Attenuation of Ground Motion from Shallow Induced Earthquakes, Case Study: Preston New Road, United Kingdom

Suroyo, Pungky M ORCID: 0000-0001-9317-9924 and Edwards, Benjamin ORCID: 0000-0001-5648-8015 (2023) Rapid Near-Field Attenuation of Ground Motion from Shallow Induced Earthquakes, Case Study: Preston New Road, United Kingdom. SEISMOLOGICAL RESEARCH LETTERS, 94 (3). pp. 1417-1428.

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Abstract

<jats:title>Abstract</jats:title> <jats:p>Ground motions from shallow induced earthquakes and tectonic seismicity were investigated in this study by directly modeling the seismic attenuation quality factor (Q) using spectral fitting and coda envelope decay methods. We use data from the Preston New Road (PNR) shale gas induced seismicity sequences near Blackpool, United Kingdom, in 2018 and 2019, in addition to regional tectonic events in the United Kingdom. Our results show that the local Q obtained from the induced seismic sequences at PNR, attributed to shallower layers in the crust, leads to a rapid rate of near-field decay (sudden loss in amplitude of earthquake signal over a short distances), with significantly stronger attenuation than observed for regional events. We furthermore find that estimates of Q are nonunique to a given record, differing both with the method and the analysis windows used, particularly at high frequency. These differences can be attributed to the different modeling methodologies (e.g., different assumptions) or to fundamental differences in physical attenuation processes within the seismic wavefield itself, which traverses multiple ray paths and comprises various phases. Our results indicate that to model ground motions for shallow earthquakes, it is important to consider the composite Q along a specific path rather than an average regional Q. To this extent, a depth-dependent attenuation model is considered crucial to bridge the gap between shallow induced earthquakes and tectonic seismicity.</jats:p>

Item Type:	Article
Divisions:	Faculty of Science and Engineering > School of Environmental Sciences
Depositing User:	Symplectic Admin
Date Deposited:	12 Dec 2023 09:31
Last Modified:	23 Jan 2024 02:30
DOI:	10.1785/0220220177
Related URLs:	Author Publisher
URI:	https://livrepository.liverpool.ac.uk/id/eprint/3177272