Earthquake-induced soft-sediment deformations and seismically amplified erosion rates recorded in varved sediments of Köyceğiz Lake (SW Turkey)

Handle URI:
http://hdl.handle.net/10754/613301
Title:
Earthquake-induced soft-sediment deformations and seismically amplified erosion rates recorded in varved sediments of Köyceğiz Lake (SW Turkey)
Authors:
Avsar, Ulas ( 0000-0002-3224-8399 ) ; Jonsson, Sigurjon ( 0000-0001-5378-7079 ) ; Avşar, Özgür; Schmidt, Sabine
Abstract:
Earthquake-triggered landslides amplify erosion rates in catchments, i.e. catchment response to seismic shocks (CR). In addition to historical eyewitness accounts of muddy rivers implying CRs after large earthquakes, several studies have quantitatively reported increased sediment concentrations in rivers after earthquakes. However, only a few paleolimnological studies could detect CRs within lacustrine sedimentary sequences as siliciclastic-enriched intercalations within background sedimentation. Since siliciclastic-enriched intercalations can easily be of non-seismic origin, their temporal correlation with nearby earthquakes is crucial to assign a seismic triggering mechanism. In most cases, either uncertainties in dating methods or the lack of recent seismic activity has prevented reliable temporal correlations, making the seismic origin of observed sedimentary events questionable. Here, we attempt to remove this question mark by presenting sedimentary traces of CRs in the 370-year-long varved sequence of Köyceğiz Lake (SW Turkey) that we compare with estimated peak ground acceleration (PGA) values of several nearby earthquakes. We find that earthquakes exceeding estimated PGA values of ca. 20 cm/s2 can induce soft-sediment deformations (SSD), while CRs seem only to be triggered by PGA levels higher than 70 cm/s2. In Köyceğiz Lake, CRs produce Cr- and Ni-enriched sedimentation due to the seismically mobilized soils derived from ultramafic rocks in the catchment. Given the varve chronology, the residence time of the seismically mobilized material in the catchment is determined to be 5 to 10 years.
KAUST Department:
Earth Science and Engineering Program
Citation:
Earthquake-induced soft-sediment deformations and seismically amplified erosion rates recorded in varved sediments of Köyceğiz Lake (SW Turkey) 2016 Journal of Geophysical Research: Solid Earth
Publisher:
Wiley-Blackwell
Journal:
Journal of Geophysical Research: Solid Earth
Issue Date:
6-Jun-2016
DOI:
10.1002/2016JB012820
Type:
Article
ISSN:
21699313
Sponsors:
This research was funded by King Abdullah University of Science and Technology (KAUST). We are grateful to J. Harrington (KAUST) for his constructive comments, which helped us to improve the manuscript. For the varve counting, we acknowledge Ezgi Ünal İmer (Uni. of Queensland); Tolga Necati Yaylım and Çağdaş Sağır (Muğla Sıtkı Koçman University); Rishabh Dutta, Ayrat Abdullin, Renier Ladron De Guevara, Wenbin Xu, Hannes Vasyura-Bathke, and Joël Ruch (KAUST). We also would like to thank to Jasper Moernaut and an anonymous reviewer for their constructive comments. The data for this paper are available by contacting the corresponding author.
Additional Links:
http://doi.wiley.com/10.1002/2016JB012820
Appears in Collections:
Articles

Full metadata record

DC FieldValue Language
dc.contributor.authorAvsar, Ulasen
dc.contributor.authorJonsson, Sigurjonen
dc.contributor.authorAvşar, Özgüren
dc.contributor.authorSchmidt, Sabineen
dc.date.accessioned2016-06-16T09:32:32Z-
dc.date.available2016-06-16T09:32:32Z-
dc.date.issued2016-06-06-
dc.identifier.citationEarthquake-induced soft-sediment deformations and seismically amplified erosion rates recorded in varved sediments of Köyceğiz Lake (SW Turkey) 2016 Journal of Geophysical Research: Solid Earthen
dc.identifier.issn21699313-
dc.identifier.doi10.1002/2016JB012820-
dc.identifier.urihttp://hdl.handle.net/10754/613301-
dc.description.abstractEarthquake-triggered landslides amplify erosion rates in catchments, i.e. catchment response to seismic shocks (CR). In addition to historical eyewitness accounts of muddy rivers implying CRs after large earthquakes, several studies have quantitatively reported increased sediment concentrations in rivers after earthquakes. However, only a few paleolimnological studies could detect CRs within lacustrine sedimentary sequences as siliciclastic-enriched intercalations within background sedimentation. Since siliciclastic-enriched intercalations can easily be of non-seismic origin, their temporal correlation with nearby earthquakes is crucial to assign a seismic triggering mechanism. In most cases, either uncertainties in dating methods or the lack of recent seismic activity has prevented reliable temporal correlations, making the seismic origin of observed sedimentary events questionable. Here, we attempt to remove this question mark by presenting sedimentary traces of CRs in the 370-year-long varved sequence of Köyceğiz Lake (SW Turkey) that we compare with estimated peak ground acceleration (PGA) values of several nearby earthquakes. We find that earthquakes exceeding estimated PGA values of ca. 20 cm/s2 can induce soft-sediment deformations (SSD), while CRs seem only to be triggered by PGA levels higher than 70 cm/s2. In Köyceğiz Lake, CRs produce Cr- and Ni-enriched sedimentation due to the seismically mobilized soils derived from ultramafic rocks in the catchment. Given the varve chronology, the residence time of the seismically mobilized material in the catchment is determined to be 5 to 10 years.en
dc.description.sponsorshipThis research was funded by King Abdullah University of Science and Technology (KAUST). We are grateful to J. Harrington (KAUST) for his constructive comments, which helped us to improve the manuscript. For the varve counting, we acknowledge Ezgi Ünal İmer (Uni. of Queensland); Tolga Necati Yaylım and Çağdaş Sağır (Muğla Sıtkı Koçman University); Rishabh Dutta, Ayrat Abdullin, Renier Ladron De Guevara, Wenbin Xu, Hannes Vasyura-Bathke, and Joël Ruch (KAUST). We also would like to thank to Jasper Moernaut and an anonymous reviewer for their constructive comments. The data for this paper are available by contacting the corresponding author.en
dc.language.isoenen
dc.publisherWiley-Blackwellen
dc.relation.urlhttp://doi.wiley.com/10.1002/2016JB012820en
dc.rightsThis is the peer reviewed version of the following article: Avşar, U., S. Jónsson, Ö. Avşar, and S. Schmidt (2016), Earthquake-induced soft-sediment deformations and seismically amplified erosion rates recorded in varved sediments of Köyceğiz Lake (SW Turkey), J. Geophys. Res. Solid Earth, 121, which has been published in final form at http://doi.wiley.com/10.1002/2016JB012820. This article may be used for non-commercial purposes in accordance With Wiley Terms and Conditions for self-archiving.en
dc.titleEarthquake-induced soft-sediment deformations and seismically amplified erosion rates recorded in varved sediments of Köyceğiz Lake (SW Turkey)en
dc.typeArticleen
dc.contributor.departmentEarth Science and Engineering Programen
dc.identifier.journalJournal of Geophysical Research: Solid Earthen
dc.eprint.versionPost-printen
dc.contributor.institutionDepartment of Geological Engineering; Muğla Sıtkı Koçman University; TR Muğla Turkeyen
dc.contributor.institutionUMR 5805 EPOC OASU; University of Bordeaux; Pessac Franceen
dc.contributor.affiliationKing Abdullah University of Science and Technology (KAUST)en
kaust.authorAvsar, Ulasen
kaust.authorJonsson, Sigurjonen
All Items in KAUST are protected by copyright, with all rights reserved, unless otherwise indicated.