Transient aseismic vertical deformation across the steeply‐dipping Pisia‐Skinos normal fault (Gulf of Corinth, Greece)

Mildon, Z.K. and Dierks, M. and Roberts, Gerald P. and Faure Walker, J. and Ganas, A. and Papanikolaou, I. and Sakas, V. and Robertson, Jenni and Sgambato, Claudia and Mitchell, Sam (2024) Transient aseismic vertical deformation across the steeply‐dipping Pisia‐Skinos normal fault (Gulf of Corinth, Greece). Tectonics 43 (8), e2024TC008276. ISSN 0278-7407.

Abstract

Geodetically‐derived deformation rates are sometimes used to infer seismic hazard, implicitly assuming that short‐term (annual‐decadal) deformation is representative of longer‐term deformation. This is despite geological observations indicating that deformation/slip rates are variable over a range of timescales. Using geodetic data from 2016 to 2021, we observe an up to 7‐fold increase in vertical deformation rate in mid‐2019 across the Pisia‐Skinos normal fault in Greece. We hypothesize that this deformation is aseismic as there is no temporally correlated increase in the earthquake activity (M > 1). We explore four possible physical mechanisms, and our preferred hypothesis is that the transient deformation is caused by centimeter scale slip in the upper 5 km of the Pisia fault zone. This is the first observation of shallow tectonic (i.e., not related to human activities) aseismic deformation on a normal fault globally. Our results suggest that continental normal faults can exhibit variable deformation over shorter timescales than previously observed, and thus care should be taken when utilizing geodetic rates to quantify seismic hazard.

Metadata

Statistics

DownloadsShow export options

Export as XMLJSONCSV

Activity Overview

6 month trend

1Download

6 month trend

11Hits

Additional statistics are available via IRStats2.

See more details

Blogged by 1

Posted by 12 X users

2 readers on Mendeley

Archive Staff Only (login required)

Edit/View Item