Abstract
During a protracted explosive eruption, at least four laterally extensive and sustained pyroclastic density currents radiated across the flanks of Las Cañadas volcano, Tenerife. Each pyroclastic current developed marked local and regional spatial variations in response to the incised, gently concave substrate topography. The locations of these variations shifted in space as rapid sedimentation from the current progressively buried and modified the topography. This complex, shifting response of the density currents to minor topographic variations has been reconstructed in high-resolution over a wide area (>500 km2) using the internal architecture of cryptic time-surfaces (entrachrons) marked by compositional zoning in the deposit, including variations in clast types. Valley-side field relations reveal that the currents were density-stratified. Yet, at a single instant in time, the lower levels of each current comprised a granular-fluid at some locations but were fully dilute and turbulent at others. Moreover, the locations of these variations shifted geographically as the topography changed during the eruption. The variations within the current are recorded by numerous superbly exposed gradational transitions from various stratified to massive lithofacies, both laterally and in the downcurrent direction. Individual currents were regionally widespread and travelled >15 km, but deposited only in longitudinally restricted, localised zones that spanned several small valleys and interfluves. The currents bypassed slopes up- and downcurrent of the restricted depositional zones, without depositing. The locations of deposition then gradually shifted with time, such that the extensive deposit sheet was gradually assembled beneath the sustained current in a diachronous fashion. Onlap relationships of internal entrachrons reveal that the base of the ignimbrite sheet and even the bases of individual flow-units are markedly diachronous. Deposition of a flow-unit commenced and ceased at different times in different places. This study suggests that in hazard assessments: (a) models of density currents that incorporate only pre-existing topography (e.g. from DEMs) may give misleading results in the case of sustained currents because sedimentation from these significantly modifies the topography during emplacement, altering flow paths; (b) frequencies and scales of previous pyroclastic currents determined from pyroclastic successions are likely to be significantly under-estimated because currents commonly bypass without leaving a deposit record; and (c) even where preservation appears to be complete, an ignimbrite at a single exposure commonly will not record the current’s entire flow history at that site.
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References
Alexander J, Morris M (1994) Observations on experimental, non-channelized, high-concentration turbidity currents and variations in deposits around obstacles. J Sed Res A64:899–909
Allen SR, Cas RAF (1998) Lateral variations within coarse co-ignimbrite lithic breccias of the Kos Plateau Tuff Greece. Bull Volcanol 59:356–377
Amy LA, Kneller BC, McCaffrey WD (2007) Facies architecture of the Grès de Peïra cava, SE France: landward stacking patterns in ponded turbidite basins. J Geol Soc 164:143–162
Ancochea E, Fuster JM, Ibarrola E, Cendrero A, Coello J, Hernan F, Cantagrel JM, Jamond C (1990) Volcanic evolution of the island of Tenerife (Canary Islands) in the light of new K–Ar data. J Volcanol Geotherm Res 44:231–249
Ancochea E, Huertas MJ, Cantagrel JM, Coello J, Fuster JM, Arnuad N, Ibarrola E (1999) Evolution of the Cañadas edifice and its implications for the origin of the Cañadas Caldera (Tenerife, Canary Islands). J Volcanol Geotherm Res 88:177–199
Andrews GDM, Branney MJ (2011) Emplacement and rheomorphic deformation of a large, lava-like rhyolite ignimbrite: Grey’s landing, southern Idaho. Geol Soc Am Bull 123:725–743
Andrews BJ, Manga M (2011) Effects of topography on pyroclastic density current runout and formation of co-ignimbrites. Geology 39:1099–1102
Andrews BJ, Manga M (2012) Experimental study of turbulence, sedimentation, and co-ignimbrite mass partitioning in dilute pyroclastic density currents. J Volcanol Geotherm Res 225–226:30–44
Baines PG (1995) Topographic effects on stratified flows. Cambridge University Press, Cambridge
Best JL, Kostaschuk RA, Peakall J, Villard PV, Franklin M (2005) Whole flow field dynamics and velocity pulsing within natural sediment-laden underflows. Geology 33:765–768
Bogaard P (1998) 40Ar/39Ar ages of Pliocene–Pleistocene fallout tephra units and volcaniclastic deposits in the sedimentary aprons of Gran Canaria and Tenerife (sites 953, 954 and 956). Proc Ocean Drill Program Sci Results 157:329–341
Bourdier J, Abdurachman EK (2001) Decoupling of small-volume pyroclastic flows and related hazards at Merapi volcano, Indonesia. Bull Volcanol 63:309–325
Branney MJ, Kokelaar BP (1992) A reappraisal of ignimbrite emplacement: progressive aggradation and changes from particulate to non-particulate flow during emplacement of high-grade ignimbrite. Bull Volcanol 54:504–520
Branney MJ, Kokelaar BP (1994) Volcanotectonic faulting, soft-state deformation and rheomorphism of tuffs during development of a piecemeal caldera, English Lake District. Geol Soc Am Bull 109:507–530
Branney MJ, Kokelaar BP (1997) Giant bed from a sustained catastrophic density current flowing over topography: Acatlan ignimbrite, Mexico. Geology 25:115–118
Branney MJ, Kokelaar P (2002) Pyroclastic density currents and the sedimentation of ignimbrites. Geol Soc Lond Mem 27:1–152
Branney MJ, Barry TL, Godchaux M (2004) Sheathfolds in rheomorphic ignimbrites. Bull Volcanol 66:485–491
Brown RJ, Barry TL, Branney MJ, Pringle MS, Bryan SE (2003) The Quaternary pyroclastic succession of southern Tenerife, Canary Islands: explosive eruptions, related subsidence and sector collapse. Geol Mag 140:265–288
Brown RJ, Branney MJ (2004a) Event-stratigraphy of a caldera-forming ignimbrite eruption on Tenerife: the 273 ka Poris Formation. Bull Volcanol 66:392–416
Brown RJ, Branney MJ (2004b) Bypassing and diachronous deposition from pyroclastic density currents: evidence from a giant regressive bedform (Poris Formation, Tenerife). Geology 32:445–448
Brown RJ, Branney MJ, Maher C, Dávila-Harris P (2010) Origin of accretionary lapilli within ground-hugging density currents: Evidence from pyroclastic couplets on Tenerife. Bull Geol Soc Am 122:305–320
Brown RJ, Bonadonna C, Durant AJ (2012) A review of ash aggregation. Phys Chem Earth 45–46:65–78
Bryan SE, Marti J, Cas RAF (1998a) Stratigraphy of the Bandas del Sur Formation: an extracaldera record of Quaternary phonolitic explosive volcanism from the Las Cañadas edifice, Tenerife (Canary Islands). Geol Mag 135:605–636
Bryan SE, Marti J, Cas RAF (1998b) Lithic breccias in intermediate volume phonolitic ignimbrites, Tenerife (Canary Islands): constraints on pyroclastic flow depositional processes. J Volcanol Geotherm Res 81:269–296
Bryan SE, Marti J, Cas RAF, Marti J (2000) The 0.57 Ma Plinian eruption of the Granadilla Member, Tenerife (Canary Islands): an example of complexity in eruption dynamics and evolution. J Volcanol Geotherm Res 103:209–238
Burgisser A, Bergantz GW (2002) Reconciling pyroclastic flow and surge: the multiphase physics of pyroclastic density currents. Earth Planet Sci Lett 202:405–418
Bursik MI, Woods AW (2000) The effects of topography on sedimentation from particle-laden turbulent density currents. J Sed Res 70:53–63
Calder ES, Cole PD, Dade WB, Druitt TH, Hoblitt RP, Huppert HE, Ritchie L, Sparks RSJ, Young SR (1999) Mobility of pyroclastic flows and surges at the Soufriere Hills Volcano, Montserrat. Geophys Res Lett 26:537–540
Carrasco-Núñez G, Branney MJ (2005) Progressive assembly of a massive layer of ignimbrite with normal-to-reverse compositional zoning: the Zaragoza ignimbrite of central Mexico. Bull Volcanol 68:3–20
Choux CM, Druitt TH (2002) Analogue study of particle segregation in PDCs, with implications for the emplacement mechanisms of large ignimbrites. Sedimentology 49:907–928
Dade WB, Huppert HE (1996) Emplacement of the Taupo ignimbrite by a dilute, turbulent flow. Nature 381:509–512
Dávila Harris P (2009) Explosive ocean-island volcanism: the 1.8–0.7 Ma explosive eruption history of Cañadas volcano recorded by the pyroclastic successions around Adeje and Abona, southern Tenerife, Canary Islands. Unpub PhD thesis, Univ Leics, UK
Dávila Harris P, Branney MJ, Storey M (2011) Large eruption-triggered ocean-island landslide at Tenerife: Onshore record and long-term effects on hazardous pyroclastic dispersal. Geology 39:951–954
Dávila Harris P, Ellis BS, Branney MJ, Carrasco-Nunez G (2013) Physical volcanology and geochemistry of a vitric spatter-bearing ignimbrite: the Quaternary Adeje Formation, Cañadas volcano, Tenerife. Bull Volcanol 75:722
Denlinger RP, Iverson RM (2001) Flow of variably fluidized granular masses across three dimensional terrain, 2. Numerical predictions and experimental texts. J Geophys Res 106:553–566
De Rita D, Giordano G, Milli S (1998) Forestepping-backstepping stacking patterns of volcaniclastic successions: Roccamonfina volcano, Italy. J Volcanol Geotherm Res 80:155–178
Doronzo DM, Valentine GA, Dellino P, de Tullio MD (2010) Numerical analysis of the effect of topography on deposition from dilute pyroclastic density currents. Earth Planet Sci Lett 300:164–173
Doronzo DM, Dellino (2012) Interaction between pyroclastic density currents and buildings: numerical simulation and first experiments. Earth Planet Sci Lett 310:286–292
Druitt TH (1998) Pyroclastic density currents: In: Gilbert JS, Sparks RSJ (eds) The physics of explosive eruptions. Geol Soc London Spec Pub 145:145–182
Druitt TH, Calder E, Cole PD, Hoblitt RP, Loughlin S, Norton GE, Ritchie LJ, Sparks RSJ, Voight B (2002) Small-volume, highly mobile pyroclastic flows formed by rapid sedimentation from pyroclastic surges at Soufriere Hills Volcano, Montserrat: an important volcanic hazard. In: Druitt TH, Kokelaar BP (eds) The eruption of Soufrière Hills Volcano, Montserrat. Geol Soc Lond Mem 21:263–279
Dufek J, Wexler J, Manga M (2009) Transport capacity of pyroclastic density currents: Experiments and models of substrate–flow interaction. J Geophys Res 114:B11203–B11215. doi:10.1029/2008JB006216
Edgar CJ, Wolff JA, Nichols HJ, Cas CAF, Marti J (2002) A complex quaternary ignimbrite-forming phonolite eruption: the Poris Member of the Diego Hernandez Formation (Tenerife, Canary Islands). J Volcanol Geotherm Res 118:99–130
Fierstein J, Hildreth W (1992) The Plinian eruptions of 1912 at Novarupta, Katmai National Park, Alaska. Bull Volcanol 54:646–684
Fierstein J, Wilson CJN (2005) Assembling an ignimbrite: compositionally defined eruptive packages in the 1912 Valley of Ten Thousand Smokes ignimbrite, Alaska. Geol Soc Am Bull 117:1094–1107
Fisher RV (1966) Mechanism of deposition from pyroclastic flows. Am J Sci 264:350–363
Fisher RV (1990) Transport and deposition of a pyroclastic surge across an area of high relief—the 18 May 1980 eruption of Mount St. Helens, Washington. Geol Soc Am Bull 102:1038–1054
Fisher RV, Orsi G, Ort M, Heiken G (1993) Mobility of a large-volume pyroclastic flow—emplacement of the Campanian ignimbrite, Italy. J Volcanol Geotherm Res 56:205–220
Fisher RV (1995) Decoupling of pyroclastic currents—hazards assessment. J Volcanol Geotherm Res 66:257–263
Garcia MH, Parker G (1989) Experiments on hydraulic jumps in turbidity currents near a canyon-fan transition. Science 245:393–396
Gertisser R, Cassidy NJ, Charbonnier SJ (2012) Overbank block-and-ash flow deposits and the impact of valley-derived, unconfined flows on populated areas at Merapi volcano, Java, Indonesia. Nat Hazards 60:623–648
Giordano G (1998) Facies characteristics and magma-water interaction of the White Trachytic Tuffs (Roccamonfina Volcano, Southern Italy). Bull Volcanol 60:10–26
Girolami L, Roche O, Druitt TH, Corpetti T (2010) Velocity fields and depositional processes in laboratory ash flows. Bull Volcanol 72:747–759. doi:10.1007/s00445-010-0356-9
Gray TE, Alexander J, Leeder MR (2005) Quantifying velocity and turbulence structure in depositing sustained turbidity currents across breaks in slope. Sedimentology 54:467–488. doi:10.1111/j.1365-3091.2005.00705.x
Gurioli L, Sulpizio R, Cioni R, Sbrana A, Santacroce R, Luperini W, Andronico D (2010) Pyroclastic flow hazard assessment at Somma-Vesuvius based on geological record. Bull Volcanol 72:1021–1038
Huertas MJ, Arnaud NO, Ancochea E, Cantagrel JM, Fúster JM (2002) 40Ar/39Ar stratigraphy of pyroclastic units from the Cañadas volcanic edifice (Tenerife, Canary Islands) and their bearing on the structural evolution. J Volcanol Geotherm Res 115:351–365
Kassem A, Imran J (2001) Simulation of turbid underflows generated by the plunging of a river. Geology 29:655–659
Kneller B, Edwards D, McCaffrey W, Moore R (1991) Oblique reflection of turbidity currents. Geology 19:250–252
Kneller B, Branney MJ (1995) Sustained high-density turbidity currents and the deposition of thick massive sands. Sedimentology 42:607–617
Kneller B, McCaffrey W (1999) Depositional effects of flow non-uniformity and stratification within turbidity currents approaching a bounding slope: deflection, reflection, and facies variation. J Sed Res 69:980–991
Kokelaar P (1992) Ordovician marine volcanic and sedimentary record of rifting and volcanotectonics. Snowdon, Wales, United Kingdom. Geol Soc Am Bull 104:1433–1455
Komar PD (1971) Hydraulic jumps in turbidity currents. Geol Soc Am Bull 82:1477–1488
Kröchert J, Buchner E (2009) Age distribution of cinder cones within the Bandas del Sur formation, southern Tenerife, Canary Islands. Geol Mag 146:161–172
Kubo Y (2004) Experimental and numerical study of topographic effects on deposition from two-dimensional, particle-driven density currents. Sediment Geol 164:311–326
Legros F, Kelfoun K (2000) On the ability of pyroclastic flows to scale topographic obstacles. J Volcanol Geotherm Res 98:235–241
Lirer L, Petrosino P, Alberico I, Postiglione I (2001) Long-term volcanic hazard forecasts based on Somma-Vesuvio past eruptive activity. Bull Volcanol 63:45–60
Loughlin SC, Calder ES, Clarke A, Cole PD, Luckett R, Mangan MT, Pyle DM, Sparks RSJ, Voight B, Watts RB (2002) Pyroclastic flows and surges generated by the 25 June 1997 dome collapse, Soufrière Hills volcano, Montserrat. In: Druitt TH, Kokelaar BP (eds) The eruption of Soufrière Hills Volcano, Montserrat. Geol Soc London Memoir 21:181–209
Lube G, Cronin SJ, Thouret JC, Surono (2011) Kinematic characteristics of pyroclastic density currents at Merapi and controls on their avulsion from natural and engineered channels. Geol Soc Am Bull 123:1127–1140
Macías JL, Espíndola JM, Bursik M, Sheridan MF (1998) Development of lithic-breccias in the 1982 pyroclastic flow deposits of El Chichón volcano, Mexico. J Volcanol Geotherm Res 83:173–196
Morris SA, Alexander J (2003) Changes in flow direction at a point caused by obstacles during passage of a density current. J Sediment Res 73:621–629
Marti J, Mitjavila J, Arana V (1994) Stratigraphy, structure and geochronology of the Las Cañadas caldera (Tenerife, Canary Islands). Geol Mag 131:715–727
Mulder T, Alexander J (2001) Abrupt change in slope causes variation in the deposit thickness of concentrated particle-driven density currents. Mar Geol 175:221–235
Pittari A, Cas RAF, Edgar CJ, Nichols HJ, Wolff JA, Marti J (2006) The influence of palaeotopography on facies architecture and pyroclastic flow processes of a lithic-rich ignimbrite in a high gradient setting: the Abrigo ignimbrite, Tenerife, Canary Islands. J Volcanol Geotherm Res 152:273–315
Robool MJ, Smith AL, Wright JV (1987) Lithic breccias in pyroclastic flow deposits on St. Kitts, West Indies. Bull Volcanol 49:694–707
Roche O, Gilbertson MA, Phillips JC, Sparks RSJ (2005) Inviscid behaviour of fines-rich pyroclastic flows inferred from experiments on gas-particles mixtures. Earth Planet Sci Lett 240:401–414. doi:10.1016/j.epsl.2005.09.053
Roche O, Atalli M, Mangeney A, Lucas A (2011) On the run-out distance of geophysical gravitational flows: insight from fluidized granular collapse experiments. Earth Planet Sci Lett 311:375–385. doi:10.1016/j.epsl.2011.09.023
Roche O (2012) Depositional processes and gas pore pressure in pyroclastic flows: an experimental perspective. Bull Volcanol 74:1807–1820. doi:10.1007/s00445-012-0639-4
Rossano S, Mastroloronzo G, De Natale G (2004) Numerical simulation of pyroclastic density currents on Campi Flegrei topography: a tool for statistical hazard estimation. J Volcanol Geotherm Res 132:1–14
Schumacher R, Schmincke H-U (1990) The lateral facies of ignimbrites at Laacher See volcano. Bull Volcanol 52:271–285
Scott WE, Hoblitt RP, Torres RC, Self S, Martinez ML, Nillos TJ (1996) Pyroclastic flows of the June 15 1991, climactic eruption of Mount Pinatubo. In: Newhall CG, Punongbayan S (eds) Fire and mud: eruptions of Pinatubo, Philippines. Philippine Institute of Volcanology and Seismology, Quenzen City. University of Washington Press, Seattle, pp 545–570
Smith N (2012) Near-vent processes of the 273 ka Poris eruption (Tenerife). PhD thesis, University of Liverpool
Sohn YK (1997) On traction-carpet sedimentation. J Sed Res 67:502–509
Stevenson CJ, Talling PJ, Wynn RB, Masson DG, Hunt JE, Frenz M, Akhmetzhanhov A, Cronin BT (2013) The flows that left no trace: very large-volume turbidity currents that bypassed sediment through submarine channels without eroding the sea floor. Mar Pet Geol 41:186–205
Sulpizio R, Mele D, Dellino P, La Volpe L (2007) Deposits and physical properties of pyroclastic density currents during complex Subplinian eruptions: the AD 472 (Pollena) eruption of Somma Vesuvius, Italy. Sedimentology 54:607–635
Sulpizio R, Dellino P (2008) Sedimentology, depositional mechanisms and pulsating behaviour of pyroclastic density currents. In: Gottsmann J, Marti J (eds) Caldera volcanism: analysis, modelling and response. Developments in volcanology, vol 10. Elsevier, Amsterdam, pp 57–96
Sulpizio R, De Rosa R, Donato P (2008) The influence of variable topography on the depositional behaviour of pyroclastic density currents: the examples of the Upper Pollena eruption (Salina Island, southern Italy). J Volcanol Geotherm Res 175:367–385
Sulpizio R, Bonasia R, Dellino O, Mele D, Di Vito MA, La Volpe L (2010) The Pomici di Avellino eruption of Somma-Vesuvius (3.0 ka BP). Part II: sedimentology and physical volcanology of pyroclastic density current deposits. Bull Volcanol 72:559–577
Valentine GA (1987) Stratified flow in pyroclastic surges. Bull Volcanol 49:616–630
Valentine GA, Wohletz KH, Kieffer SW (1992) Effects of topography on facies and compositional zonation in caldera-related ignimbrites. Geol Soc Am Bull 104:154–165
Van Andel TH, Komar PD (1969) Ponded sediments of the Mid-Atlantic ridge between 22 and 23 North. Geol Soc Am Bull 80:1163–1190
Van Eaton AR, Wilson CJN (2013) The nature, origins and distribution of ash aggregates in a large-scale wet eruption deposit: Oruanui, New Zealand. J Volcanol Geotherm Res 250:129–154
Walker GPL, Wilson CJN, Froggatt PC (1981) An ignimbrite veneer deposit—the trail marker of a pyroclastic flow. J Volcanol Geotherm Res 9:409–421
Watts AB, Masson DG (2001) New sonar evidence for recent catastrophic collapses of the north flank of Tenerife, Canary Islands. Bull Volcanol 63:8–19
Wilson CJN, Walker GPL (1985) The Taupo eruption, New Zealand: II. The Taupo Ignimbrite. Phil Trans Roy Soc London, Series A—Math Phys Eng Sci 314:229–310
Wilson CJN (2001) the 26.5 ka Oruanui eruption, New Zealand: an introduction and overview. J Volcanol Geotherm Res 112:133–174
Woods AW, Bursik MI, Kurbatov AV (1998) The interaction of ash flows with ridges. Bull Volcanol 60:38–51
Acknowledgements
We thank Natasha Smith, Peter Kokelaar, Pablo Dávila-Harris, Steve Self and Jan Zalasiewicz for many useful discussions. We thank Brittany Brand and Roberto Sulpizio for critical reviews that greatly improved the manuscript and Michael Manga for reviews and editorship.
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Brown, R.J., Branney, M.J. Internal flow variations and diachronous sedimentation within extensive, sustained, density-stratified pyroclastic density currents flowing down gentle slopes, as revealed by the internal architectures of ignimbrites on Tenerife. Bull Volcanol 75, 727 (2013). https://doi.org/10.1007/s00445-013-0727-0
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DOI: https://doi.org/10.1007/s00445-013-0727-0