Article (Scientific journals)
Characterizing Stalagmites’ Eigenfrequencies by Combining In Situ Vibration Measurements and Finite Element Modeling Based on 3D Scans
Martin, Aurélie; lecocq, Thomas; Hinzen, Klaus-G. et al.
2020In Geosciences, 10 (10)
Peer Reviewed verified by ORBi
 

Files


Full Text
geosciences-10-00418-v4.pdf
Publisher postprint (2.93 MB)
Request a copy

All documents in ORBi are protected by a user license.

Send to



Details



Keywords :
cave; stalagmite; natural frequency; 3D scan; numerical modeling; ambient seismic noise
Abstract :
[en] Broken or deformed speleothems have been used as indicators of paleo-earthquakes since the 1990s; however, a causal link is difficult to prove except for some thin speleothems. In contrast, the presence of intact speleothems permits estimating an upper limit of the level of horizontal ground motions of past seismicity in the area. The natural frequencies of speleothems are fundamental parameters for their response to earthquakes. This study proposes a new method of in situ characterization of these natural frequencies. Tested in the Han-sur-Lesse cave (Belgian Ardennes), the method is based on recording the ambient seismic noise using three-component sensors on a stalagmite and a 3D laser scan of its shape. The ambient seismic noise records allow a precise determination of the eigenfrequencies of the stalagmite. In addition, numerical models based on the 3D scan show good consistency between measured and modeled data. The joint analysis of these two techniques concludes that the shape of the stalagmite (elliptical cross-section and shape irregularities) influence the eigenfrequencies and polarization of the modes while also causing a near-orthogonal split of natural frequencies. The motions recorded on the stalagmite show significant amplification compared to those recorded at the free surface outside the cave, which has a strong impact on seismic hazard assessment based on speleothems.
Disciplines :
Earth sciences & physical geography
Author, co-author :
Martin, Aurélie  ;  Université de Liège - ULiège > Département de Géologie > AGEs > Doct. sc. (géol. - paysage)
lecocq, Thomas;  Observatoire Royal de Belgique - ORB > Séismologie-Gravimètrie
Hinzen, Klaus-G.;  University of Cologne > Earthquakegeology and Archaeoseismology
Camelbeeck, Thierry;  Observatoire Royal de Belgique - ORB > Séismologie-Gravimètrie
Quinif, Yves;  Université de Mons - UMONS > Faculté Polytechnique > Géologie fondamentale et appliquée
Fagel, Nathalie  ;  Université de Liège - ULiège > Département de géologie > Argiles, géochimie et environnements sédimentaires
Language :
English
Title :
Characterizing Stalagmites’ Eigenfrequencies by Combining In Situ Vibration Measurements and Finite Element Modeling Based on 3D Scans
Publication date :
2020
Journal title :
Geosciences
eISSN :
2076-3263
Publisher :
MDPI, Basel, Switzerland
Volume :
10
Issue :
10
Peer reviewed :
Peer Reviewed verified by ORBi
Funders :
ORB - Observatoire Royal de Belgique [BE]
Available on ORBi :
since 23 October 2020

Statistics


Number of views
72 (13 by ULiège)
Number of downloads
9 (7 by ULiège)

Scopus citations®
 
5
Scopus citations®
without self-citations
5
OpenCitations
 
4

Bibliography


Similar publications



Contact ORBi