%0 Journal Article
%9 ACL : Articles dans des revues avec comité de lecture répertoriées par l'AERES
%A Chaput, M.
%A Pinel, Virginie
%A Famin, V.
%A Michon, L.
%A Froger, J. L.
%T Cointrusive shear displacement by sill intrusion in a detachment : a numerical approach
%D 2014
%L fdi:010061953
%G ENG
%J Geophysical Research Letters
%@ 0094-8276
%K sill ; detachment ; flank sliding ; La Reunion ; numerical modeling
%K REUNION
%M ISI:000334264900017
%N 6
%P 1937-1943
%R 10.1002/2013gl058813
%U https://www.documentation.ird.fr/hor/fdi:010061953
%> https://www.documentation.ird.fr/intranet/publi/2014/05/010061953.pdf
%V 41
%W Horizon (IRD)
%X Sheared sills are observed at Piton des Neiges (the eroded basaltic volcano of La Reunion) and are a suspected cause of the coeruptive flank displacement of Piton de la Fournaise in 2007. We performed a 2-D numerical study to quantify the perturbation induced by sill injection within a volcanic edifice. Magma is considered as an inviscid and pressurized fluid injected in an initially stable edifice under gravity-controlled extension. Two cases of injection are tested, in an elastic homogeneous edifice or along a detachment controlled by a friction law. We show that sill injection induces tangential displacements. This effect is strongly increased when sills are emplaced along a detachment, producing extension behind the injection and potentially ending in a large-scale flank collapse. Sill injections can thus explain the cointrusive shear deformation observed at Piton des Neiges and the tangential displacements measured at Piton de la Fournaise in 2007.
%$ 066 ; 020