caa a22 4500 475826205 CHVBK 20180406123829.0 cr unu---uuuuu 170329e20001101xx s 000 0 eng 10.1007/s004450000103 doi (NATIONALLICENCE)springer-10.1007/s004450000103 Volcano instability induced by strike-slip faulting [Elektronische Daten] [A. M. F. Lagmay, B. van Wyk de Vries, N. Kerle, D. M. Pyle] Abstract.: Analogue sand cone experiments were conducted to study instability generated on volcanic cones by basal strike-slip movement. The results of the analogue models demonstrate that edifice instability may be generated when strike-slip faults underlying a volcano move as a result of tectonic adjustment. This instability occurs on flanks of the volcano above the strike-slip shear. On the surface of the volcano this appears as a pair of sigmoids composed of one reverse and one normal fault. In the interior of the cone the faults form a flower structure. Two destabilised regions are created on the cone flanks between the traces of the sigmoidal faults. Bulging, intense fracturing and landsliding characterise these unstable flanks. Additional analogue experiments conducted to model magmatic intrusion show that fractures and faults developed within the volcanic cone due to basal strike-slip motions strongly control the path of the intruding magma. Intrusion is diverted towards the areas where previous development of reverse and normal faults have occurred, thus causing further instability. We compare our model results to two examples of volcanoes on strike-slip faults: Iriga volcano (Philippines), which underwent non-magmatic collapse, and Mount St. Helens (USA), where a cryptodome was emplaced prior to failure. In the analogue and natural examples, the direction of collapse takes place roughly parallel to the orientation of the underlying shear. The model presented proposes one mechanism for strike-parallel breaching of volcanoes, recently recognised as a common failure direction of volcanoes found in regions with transcurrent and transtensional deformation. The recognition of the effect of basal shearing on volcano stability enables prediction of the likely direction of eventual flank failure in volcanoes overlying strike-slip faults. Springer-Verlag, 2000 Volcano instability Deformation Sector collapse Strike-slip faulting Mount St. Helens Iriga Analogue modelling nationallicence Lagmay A. M. F. Department of Earth Sciences, University of Cambridge, Downing Street, Cambridge, CB2 3EQ UK aut van Wyk de Vries B. Laboratoire Magmas et Volcans, Université Blaise Pascal, 5 rue Kessler, 63038 Clermont-Ferrand, France aut Kerle N. Department of Geography, University of Cambridge, Downing Place, CB2 3EN, UK aut Pyle D. M. Department of Earth Sciences, University of Cambridge, Downing Street, Cambridge, CB2 3EQ UK aut https://doi.org/10.1007/s004450000103 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s004450000103 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Lagmay A. M. F. Department of Earth Sciences, University of Cambridge, Downing Street, Cambridge, CB2 3EQ UK aut NATIONALLICENCE 700 1- van Wyk de Vries B. Laboratoire Magmas et Volcans, Université Blaise Pascal, 5 rue Kessler, 63038 Clermont-Ferrand, France aut NATIONALLICENCE 700 1- Kerle N. Department of Geography, University of Cambridge, Downing Place, CB2 3EN, UK aut NATIONALLICENCE 700 1- Pyle D. M. Department of Earth Sciences, University of Cambridge, Downing Street, Cambridge, CB2 3EQ UK aut Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer