FN Archimer Export Format
PT J
TI Transient Groundwater Flow Through a Coastal Confined Aquifer and its Impact on Near‐Shore Submarine Slope Instability
BT 
AF SULTAN, Nabil
   GARZIGLIA, Sebastien
   BOMPAIS, Xavier
   WOERTHER, Patrice
   WITT, C
   KOPF, A
   MIGEON, Sebastien
AS 1:1;2:1;3:2;4:2;5:3;6:3;7:4,5;
FF 1:PDG-REM-GM-LAD;2:PDG-REM-GM-LAD;3:PDG-REM-RDT-SIIM;4:PDG-REM-RDT-SIIM;5:;6:;7:;
C1 Ifremer, Unité Géosciences Marines, F-29280 Plouzané, France
   Ifremer, Unité Recherche et Développements Technologiques, F-29280 Plouzané, France.
   MARUM – Center for Marine Environmental Sciences, University of Bremen, Bremen, Germany.
   Université Côte d’Azur, Observatoire de la Côte d’Azur, CNRS, IRD, Géoazur, 06560 Valbonne, France
   Sorbonne Université, UFR939, 06230 Villefranche-sur-Mer, France
C2 IFREMER, FRANCE
   IFREMER, FRANCE
   UNIV BREMEN MARUM, GERMANY
   UNIV NICE, FRANCE
   UNIV SORBONNE, FRANCE
SI BREST
SE PDG-REM-GM-LAD
   PDG-REM-RDT-SIIM
IN WOS Ifremer UPR
   copubli-france
   copubli-europe
   copubli-univ-france
IF 4.041
TC 6
UR https://archimer.ifremer.fr/doc/00643/75461/76276.pdf
LA English
DT Article
CR ESS_PENF50_2015
   STEP 2011
   STEP 2014
   STEP 2015
BO Pourquoi pas ?
   L'Europe
DE ;Nice continental slope;piezometer;pore pressure;shear zone;submarine landslide;Var delta
AB Rare in situ pore pressure and temperature data sets collected over more than one decade in a submarine landslide‐prone area off Nice (Southeast France) have been used to characterize a transient groundwater exchange between a coastal confined aquifer and the near‐shore shallow‐water submarine shelf. The near‐coast study zone is highly exposed to geohazards, and remains sadly famous for the 1979 catastrophic tsunamigenic submarine landslide with several casualties and substantial material damage. Measured pore pressure buildup does not appear to be synchronized with either the discharge of the nearby Var River or with precipitation in the Nice area. Unexpectedly, pore pressure fluctuations synchronizes well with seabed temperature trends indicating that the near‐shore submarine shelf is mainly impacted by long smooth seasonal variations. We used the pore pressure and temperature data to describe the general transport mechanisms of pore waters and show that diffusion is predominantly responsible for the near‐seabed pore pressure buildup. Based on our results and previously published geotechnical data, slope stability calculations reveal that groundwater exchange has a major impact on slope instability and shear zone formation in a prone‐to‐failure area. Minor earthquake‐induced ground accelerations seem to contribute to the near‐shore slope instability by decreasing its factor of safety. Key Points A decade of pore pressure data reveals important groundwater exchange between a coastal aquifer and a near‐shore submarine shelf Excess pore pressures are more likely the trigger of observed shear zones in a prone‐to‐failure area Earthquakes could accelerate the development of progressive slope failure by decreasing its factor of safety 
PY 2020
PD SEP
SO Journal Of Geophysical Research-earth Surface
SN 2169-9003
PU American Geophysical Union
VL 125
IS 9
UT 000592163700005
DI 10.1029/2020JF005654
ID 75461
ER

EF