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Syn-eruptive, Soft-sediment Deformation of Deposits from Dilute Pyroclastic Density Current: Triggers from Granular Shear, Dynamic Pore Pressure, Ballistic Impacts and Shock Waves : Volume 6, Issue 2 (21/05/2015)

By Douillet, G. A.

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Book Id: WPLBN0004021333
Format Type: PDF Article :
File Size: Pages 20
Reproduction Date: 2015

Title: Syn-eruptive, Soft-sediment Deformation of Deposits from Dilute Pyroclastic Density Current: Triggers from Granular Shear, Dynamic Pore Pressure, Ballistic Impacts and Shock Waves : Volume 6, Issue 2 (21/05/2015)  
Author: Douillet, G. A.
Volume: Vol. 6, Issue 2
Language: English
Subject: Science, Solid, Earth
Collections: Periodicals: Journal and Magazine Collection, Copernicus GmbH
Publication Date:
Publisher: Copernicus Gmbh, Göttingen, Germany
Member Page: Copernicus Publications


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Taisne, B., Müller, S. K., Dingwell, D. B., Tsang-Hin-Sun, È., Kueppers, U., & Douillet, G. A. (2015). Syn-eruptive, Soft-sediment Deformation of Deposits from Dilute Pyroclastic Density Current: Triggers from Granular Shear, Dynamic Pore Pressure, Ballistic Impacts and Shock Waves : Volume 6, Issue 2 (21/05/2015). Retrieved from

Description: Earth and Environmental Sciences, Ludwig-Maximilians-Universität, Munich, Germany. Soft-sediment deformation structures can provide valuable information about the conditions of parent flows, the sediment state and the surrounding environment. Here, examples of soft-sediment deformation in deposits of dilute pyroclastic density currents are documented and possible syn-eruptive triggers suggested. Outcrops from six different volcanoes have been compiled in order to provide a broad perspective on the variety of structures: Soufrière Hills (Montserrat), Tungurahua (Ecuador), Ubehebe craters (USA), Laacher See (Germany), and Tower Hill and Purrumbete lakes (both Australia).

The variety of features can be classified in four groups: (1) tubular features such as pipes; (2) isolated, laterally oriented deformation such as overturned or oversteepened laminations and vortex-shaped laminae; (3) folds-and-faults structures involving thick (>30 cm) units; (4) dominantly vertical inter-penetration of two layers such as potatoids, dishes, or diapiric flame-like structures.

The occurrence of degassing pipes together with basal intrusions suggest fluidization during flow stages, and can facilitate the development of other soft-sediment deformation structures. Variations from injection dikes to suction-driven, local uplifts at the base of outcrops indicate the role of dynamic pore pressure. Isolated, centimeter-scale, overturned beds with vortex forms have been interpreted to be the signature of shear instabilities occurring at the boundary of two granular media. They may represent the frozen record of granular, pseudo Kelvin–Helmholtz instabilities. Their recognition can be a diagnostic for flows with a granular basal boundary layer. Vertical inter-penetration and those folds-and-faults features related to slumps are driven by their excess weight and occur after deposition but penecontemporaneous to the eruption. The passage of shock waves emanating from the vent may also produce trains of isolated, fine-grained overturned beds that disturb the surface bedding without occurrence of a sedimentation phase in the vicinity of explosion centers. Finally, ballistic impacts can trigger unconventional sags producing local displacement or liquefaction. Based on the deformation depth, these can yield precise insights into depositional unit boundaries. Such impact structures may also be at the origin of some of the steep truncation planes visible at the base of the so-called chute and pool structures.

Dilute pyroclastic density currents occur contemporaneously with seismogenic volcanic explosions. They can experience extremely high sedimentation rates and may flow at the border between traction, granular and fluid-escape boundary zones. They are often deposited on steep slopes and can incorporate large amounts of water and gas in the sediment. These are just some of the many possible triggers acting in a single environment, and they reveal the potential for insights into the eruptive and flow mechanisms of dilute pyroclastic density currents.

Syn-eruptive, soft-sediment deformation of deposits from dilute pyroclastic density current: triggers from granular shear, dynamic pore pressure, ballistic impacts and shock waves

Alsop, G. I. and Marco, S.: Tsunami and seiche-triggered deformation within offshore sediments, Sediment. Geol., 261, 90–107, 2012.; Allen, J. and Banks, N.: An interpretation and analysis of recumbent-folded deformed cross-bedding, Sedimentology, 19, 257–283, 1972.; Alsop, G. and Marco, S.: Soft-sediment deformation within seismogenic slumps of the Dead Sea Basin, J. Struct. Geol., 33, 433–457, 2011.; Andrews, G. D. and Branney, M. J.: Emplacement and rheomorphic deformation of a large, lava-like rhyolitic ignimbrite: Grey's Landing, southern Idaho, Geol. Soc. Am. Bull., 123, 725–743, 2011.; Bernard, J., Kelfoun, K., Le Pennec, J.-L., and Vargas, S. V.: Pyroclastic flow erosion and bulking processes: comparing field-based vs. modeling results at Tungurahua volcano, Ecuador, B. Volcanol., 76, 1–16, 2014.; Borisov, A., Lyubimov, A., Kogarko, S., and Kozenko, V.: Instability of the surface of a granular medium behind sliding shock and detonation waves, Combust. Explo. Shock+, 3, 95–97, 1967.; Brand, B. D. and Clarke, A. B.: The architecture, eruptive history, and evolution of the Table Rock Complex, Oregon: From a Surtseyan to an energetic maar eruption, J. Volcanol. Geoth. Res., 180, 203–224, 2009.; Brand, B. D. and White, C. M.: Origin and stratigraphy of phreatomagmatic deposits at the Pleistocene Sinker Butte volcano, western Snake River Plain, Idaho, J. Volcanol. Geoth. Res., 160, 319–339, 2007.; Branney, M., Barry, T., and Godchaux, M.: Sheathfolds in rheomorphic ignimbrites, B. Volcanol., 66, 485–491, 2004.; Branney, M. J. and Kokelaar, B. P.: Pyroclastic density currents and the sedimentation of ignimbrites, Geo. Soc. Mem., 27, 143 pp., 2002.; Branney, M. J. and Kokelaar, P.: Volcanotectonic faulting, soft-state deformation, and rheomorphism of tuffs during development of a piecemeal caldera, English Lake District, Geol. Soc. Am. Bull., 106, 507–530, 1994.; Bridge, J. and Demicco, R.: Earth surface processes, landforms and sediment deposits, Cambridge University Press, 2008.; Brouillette, M.: The richtmyer-meshkov instability, Annu. Rev. Fluid Mech., 34, 445–468, 2002.; Brown, R. J., Orsi, G., and de Vita, S.: New insights into Late Pleistocene explosive volcanic activity and caldera formation on Ischia (southern Italy), B. Volcanol., 70, 583–603, 2008.; Caicedo-Carvajal, C. E., Glasser, B. J., and Shinbrot, T.: Granular flow transitions on sinusoidal surfaces, J. Fluid Mech., 556, 253–269, 2006.; Chan, M. A. and Bruhn, R. L.: Dynamic liquefaction of Jurassic sand dunes: processes, Origins, and implications, Earth Surf. Proc. Land., 39, 1478–1491, 2014.; Charbonnier, S. J. and Gertisser, R.: Field observations and surface characteristics of pristine block-and-ash flow deposits from the 2006 eruption of Merapi Volcano, Java, Indonesia, J. Volcanol. Geoth. Res., 177, 971–982, 2008.; Chen, J. and Lee, H. S.: Soft-sediment deformation structures in Cambrian siliciclastic and carbonate storm deposits (Shandong Province, China): Differential liquefaction and fluidization triggered by storm-wave loading, Sediment. Geol., 288, 81–94, 2013.; Conway, S. L., Shinbrot, T., and Glasser, B. J.: A Taylor vortex analogy in granular flows, Nature, 431, 433–437, 2004.; Crowe, B. M. and Fisher, R. V.: Sedimentary structures in base-surge deposits with special reference to cross-bedding, Ubehebe Craters, Death Valley, California, Geol. Soc. Am. Bull., 84, 663–682, 1973.; Denis, M., Guiraud, M., Konaté, M., and Buoncristiani, J.-F.: Subglacial deformation and water-pressure cycles as a key for understanding ice stream dynamics: evidence from the Late Ordovician succession of the Djado Basin (Niger), Int. J. Earth Sci., 99, 1399–1425, 2010.; Doronzo, D. M. and Dellino, P.: Pyroclastic density currents and local topography as seen with the conveyer model, J. Volcanol. Geoth. Res., 278, 25–39, 2014.; Leclair, S. F. and Arnott, R. W. C.: Parallel lamination formed by high-density turbidity currents, J. Sediment. Res., 75, 1–5, 2005.; Douillet


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