Gilles Grandjean

Dr. Gilles Grandjean

Natural risks and prevention, BRGM, 45060 Orléans, France
orcid

Research Focus & Metrics

Academic Career Length

34Years (1993-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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23 December 2011 in Journal of Geophysical Research: Earth Surface
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Journal Article
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CHC. Hibert
C. Hibert
AMAnne Mangeney
Anne Mangeney
Gilles GrandjeanGilles Grandjean
Gilles Grandjean
NSN. M. Shapiro
N. M. Shapiro

28 March 2014 in Journal of Geophysical Research: Earth Surface
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Journal Article
Open access
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CHC. Hibert
C. Hibert
AMAnne Mangeney
Anne Mangeney
Gilles GrandjeanGilles Grandjean
Gilles Grandjean
CBC. Baillard
C. Baillard
DRD. Rivet
D. Rivet
WCW. Crawford
W. Crawford
Since the collapse of the Dolomieu crater floor at Piton de la Fournaise Volcano (la Réunion) in 2007, hundreds of seismic signals generated by rockfalls have been recorded daily at the Observatoire Volcanologique du Piton de la Fournaise (OVPF). To study rockfall activity over a long period of time, automated methods are required to process the available continuous seismic records. We present a set of automated methods designed to identify, locate, and estimate the volume of rockfalls from their seismic signals. The method used to automatically discriminate seismic signals generated by rockfalls from other common events recorded at OVPF is based on fuzzy sets and has a success rate of 92%. A kurtosis‐based automated picking method makes it possible to precisely pick the onset time and the final time of the rockfall‐generated seismic signals. We present methods to determine rockfall locations based on these accurate pickings and a surface‐wave propagation model computed for each station using a Fast Marching Method. These methods have successfully located directly observed rockfalls with an accuracy of about 100 m. They also make it possible to compute the seismic energy generated by rockfalls, which is then used to retrieve their volume. The methods developed were applied to a data set of 12,422 rockfalls that occurred over a period extending from the collapse of the Dolomieu crater floor in April 2007 to the end of the UnderVolc project in May 2011 to identify the most hazardous areas of the Piton de la Fournaise volcano summit.

28 October 2017 in Landslides
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Journal Article
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Gerardo HerreraGerardo Herrera
Gerardo Herrera
RMRosa María Mateos
Rosa María Mateos
JGJuan Carlos García-Davalillo
Juan Carlos García-Davalillo
Gilles GrandjeanGilles Grandjean
Gilles Grandjean
EPEleftheria Poyiadji
Eleftheria Poyiadji
OJOdd Are Jensen
Odd Are Jensen

1 August 2000 in Geodinamica Acta
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Journal Article
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FGFrançois Guillocheau
François Guillocheau
CRCécile Robin
Cécile Robin
PAPascal Allemand
Pascal Allemand
SBSylvie Bourquin
Sylvie Bourquin
NBNicolas Brault
Nicolas Brault
Gilles GrandjeanGilles Grandjean
Gilles Grandjean

9 February 2011 in Hydrological Processes
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Journal Article
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JTJ. Travelletti
J. Travelletti
PSP. Sailhac
P. Sailhac
Jean-Philippe MaletJean-Philippe Malet
Jean-Philippe Malet
Gilles GrandjeanGilles Grandjean
Gilles Grandjean
JPJ. Ponton
J. Ponton

1 June 2004 in Journal of Applied Geophysics
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Journal Article
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Gilles GrandjeanGilles Grandjean
Gilles Grandjean
DLDonatienne Leparoux
Donatienne Leparoux