The Holocene syneruptive volcaniclastic debris fl ows in the Vesuvian area: Geological data as a guide for hazard assessment

Volcaniclastic debris fl ows generated in drainage basins of the Apennine mountains
of southern Campania in response to pyroclastic fall deposition from four Holocene
eruptions of Somma-Vesuvius: Avellino (3.8 ka), A.D. 79, A.D. 472, and A.D. 1631.
These syneruptive debris fl ows are lithologically homogeneous and contain more than
90% of material from the parental eruption. They differ from inter-eruptive debris
fl ows recognized in the area, which contain mixed lithologies of juvenile material
(i.e., volcanic material from different eruptions). Diffuse rill erosion generated fi nesrich
volcaniclastic fl ows (mudfl ows), whereas partial saturation of coarse ash and
lapilli generated coarser-grained debris fl ows. Lithofacies analysis shows that debris
fl ows predominate versus hyperconcentrated fl ows and normal stream-fl ow deposits.
Debris-fl ow deposits are massive, matrix supported, and have a gravelly-sandy texture.
Large blocks are scarce due to their absence in the pyroclastic source material.
Lithofacies association indicates that volcaniclastic debris-fl ow deposits aggraded
rapidly by superimposition of different surges that spontaneously developed within
the fl ow. Bulk-fl ow density ranges from 1840 to 2260 kg/m3 (mean 2035 ± 207 kg/m3).
Geological data supported some considerations of hazard assessment in the study
area and indicate that the syneruptive volcaniclastic fl ows stopped distally on active
alluvial fans.

Albore Livadie, C., ed., 1999, L’eruzione vesuviana delle Pomici di Avellino e
la facies di Palma Campania (Bronzo antico): Bari, EDIPUGLIA, p. 415.
Andronico, D., Calderoni, G., Cioni, R., Sbrana, A., Sulpizio, R., and Santacroce,
R., 1995, Geological map of Somma-Vesuvius volcano: Periodico di
Mineralogia, v. 64, p. 77–78.
Arguden, A.T., and Rodolfo, K.S., 1990, Sedimentological and dynamic differences
between hot and cold laharic debris fl ows of Mayon Volcano,
Philippines: Geological Society of America Bulletin, v. 102, p. 865–876,
doi: 10.1130/0016-7606(1990)102<0865:SADDBH>2.3.CO;2.
Barberi, F., Cioni, R., Santacroce, R., Sbrana, A., and Vecci, R., 1989, Magmatic
and phreatomagmatic phases in explosive eruptions of Vesuvius as
deduced by grain-size and component analysis of the pyroclastic deposits:
Journal of Volcanology and Geothermal Research, v. 38, p. 287–307, doi:
10.1016/0377-0273(89)90044-9.
Barberi, F., Macedonio, G., Pareschi, M.T., and Santacroce, R., 1990, Mapping
the tephra fallout risk: An example from Vesuvius (Italy): Nature, v. 344,
p. 142–144, doi: 10.1038/344142a0.
Blair, T.C., 2000, Sedimentology and progressive tectonic unconformities of
the sheetfl ood-dominated Hell’s Gate alluvial fan, Death Valley, California:
Sedimentary Geology, v. 132, p. 233–262, doi: 10.1016/S0037-
0738(00)00010-5.
Blott, S.J., and Pye, K., 2001, Gradistat: A grain size distribution and statistic
package for the analysis of unconsolidated sediments: Earth Surface Processes
and Landforms, v. 26, p. 1237–1248, doi: 10.1002/esp.261.
Bonardi, G., D’Argenio, P., and Perrone, V., 1988, Geological Map of Southern
Apennines: Consiglio Nazionale delle Ricerche (CNR), scale 1:250,000,
3 sheets Branney, M.J., and Kokelaar, P., 2002, Pyroclastic density currents and the
sedimentation of ignimbrites: Geological Society [London] Memoir 27,
143 p.
Calcaterra, D., Parise, M., Palma, B., and Pelella, L., 1999, The May 5th 1998,
landsliding event in Campania (southern Italy): Inventory of slope movements
in the Quindici area, in Yagi, N., Yamagami, T., and Jiang, J., eds.,
Proceedings of International Symposium on Slope Stability Engineering,
IS, Shikoku ‘99, Matsuyama, Shikoku, Japan, November 8–11, 1999:
Rotterdam, Balkema, p. 1361–1366.
Calcaterra, D., Parise, M., Palma, B., and Pelella, L., 2000, Multiple debris
fl ows in volcaniclastic materials mantling carbonate slopes, in Wieczorek,
G.F., and Naeser, N.D., eds., Debris-Flow Hazards Mitigation: Mechanics,
Prediction, and Assessment: Rotterdam, Balkema, p. 99–107.
Cas, A.F., and Wright, J.V., 1987, Volcanic Succession: Modern and Ancient:
London, Allen & Unwin, p. 528.
Chow, V.T., 1959, Open-channel Hydraulics: New York, McGraw-Hill, p. 465.
Cioni, R., Levi, S., and Sulpizio, R., 2000, Apulian Bronze Age pottery as a
long distance indicator of the Avellino Pumice eruption (Vesuvius, Italy),
in McGuire, B., Griffi ths, D., and Stewart, I., eds., The Archaeology of
Geological Catastrophes: Geological Society of London Special Publication
171, p. 159–177.
Cioni, R., Longo, A., Macedonio, G., Santacroce, R., Sbrana, A., Sulpizio, R.,
and Andronico, D., 2003, Assessing pyroclastic fall hazard through fi eld
data and numerical simulations: The example from Vesuvius: Journal of
Geophysical Research, v. 108, no. B2, [[is this the page info??]] 2063,
doi: 10.1029/2001JB000642.
Collins, B.D., and Dunne, T., 1986, Erosion of tephra from the 1980 eruption of
Mount St. Helens: Geological Society of America Bulletin, v. 97, p. 896–
905, doi: 10.1130/0016-7606(1986)97<896:EOTFTE>2.0.CO;2.
Costa, J.E., 1997, Hydraulic modeling for lahar hazards at Cascades volcanoes:
Environmental Engineering Geoscience, v. 3, p. 21–30.
De Crescenzo, G., and Santo, A., 1998, Analisi geomorfologica delle frane da
scorrimento-colata rapida in depositi piroclastici della Penisola Sorrentina:
Geografi a Fisica e Dinamica Quaternaria, v. 22, p. 57–72.
Denlinger, R.P., and Iverson, R.M., 2001, Flow of variably fl uidized granular
masses across three dimensional terrain, 2, Numerical predictions and
experimental texts: Journal of Geophysical Research, v. 106, no. B1,
p. 553–566.
Di Vito, M.A., Sulpizio, R., and Zanchetta, G., 1998, I depositi ghiaiosi della
valle dei Torrenti Clanio e Acqualonga (Campania centro-orientale):
Signifi cato stratigrafi co e ricostruzione paleoambientale: Il Quaternario,
v. 11, p. 273–286.
Di Vito, M.A., Isaia, R., Orsi, G., Southon, J., de Vita, S., D’Antonio, M.,
Pappalardo, L., and Piochi, M., 1999, Volcanism and deformation since
12,000 years at the Campi Flegrei caldera (Italy): Journal of Volcanology
and Geothermal Research, v. 91, p. 221–246, doi: 10.1016/S0377-
0273(99)00037-2.
Favalli, M., Pareschi, M.T., and Zanchetta, G., 2006, Delineation of syn-eruptive
fl oods in the circumvesuvian plain (southern Italy): Bulletin of Volcanology
(in press).
Folk, R.L., and Ward, W.C., 1957, Brazos river bar: A study in the signifi -
cance of grain-size parameters: Journal of Sedimentary Petrology, v. 27,
p. 3–26.
Giordano, G., De Rita, D., Fabbri, M., and Rodani, S., 2002, Facies association
of rain-generated versus crater lake-withdrawal lahar deposits from Quaternary
volcanoes, central Italy: Journal of Volcanology and Geothermal
Research, v. 118, p. 145–159, doi: 10.1016/S0377-0273(02)00254-8.
Gurioli, L., Cioni, R., Sbrana, A., and Zanella, E., 2002, Transport and deposition
of pyroclastic density currents over inhabited areas: The deposits of
the AD 79 eruption of Vesuvius at Herculaneum, Italy: Sedimentology,
v. 49, p. 929–953, doi: 10.1046/j.1365-3091.2002.00483.x.
Hungr, O., Morgan, G.C., and Kellerhals, R., 1984, Quantitative analysis of
debris torrent hazard for design of remedial measures: Canadian Geotechnical
Journal, v. 21, p. 663–677.
Inman, D.L., 1952, Measures for describing the size-distribution of sediments:
Journal of Sedimentary Petrology, v. 22, p. 125–145.
Iverson, R.M., 1997, The physics of debris fl ows: Review of Geophysics, v. 35,
p. 254–296.
Iverson, R.M., 2000, Landslide triggering by rain infi ltration: Water Resources
Research, v. 36, p. 1897–1910, doi: 10.1029/2000WR900090.
Iverson, R.M., and Reid, M.E., 1992, Gravity-driven groundwater fl ow and
slope failure potential 1, Elastic effective-stress model: Water Resources
Research, v. 28, p. 925–938, doi: 10.1029/91WR02694.
Iverson, R.M., and Vallance, J.M., 2001, New views of granular mass fl ows:
Geology, v. 29, p. 115–118, doi: 10.1130/0091-7613(2001)029<0115:
NVOGMF>2.0.CO;2.
Iverson, R.M., Schilling, S.P., and Vallance, J.W., 1998, Objective delineation
of lahar-inundation zones: Geological Society of America Bulletin,
v. 110, p. 972–984, doi: 10.1130/0016-7606(1998)110<0972:
ODOLIH>2.3.CO;2.
Iverson, R.M., Denlinger, R.P., LaHusen, R.G., and Logan, M., 2000, Twophase
debris-fl ow across 3-D terrain: Model predictions, in Wieczorek,
G.F, and Naeser, N.D., eds., Debris-Flow Hazard Mitigation, Mechanics,
Prediction, and Assessment: Taipei, Taiwan, 16–18 August 2000: Rotterdam,
Balkema, p. 521–529.
Legros, F., and Martí, J., 2001, Formation of inversely graded basal layers
in ignimbrites by progressive aggradation: Journal of Volcanology
and Geothermal Research, v. 111, p. 25–33, doi: 10.1016/S0377-
0273(01)00208-6.
Lirer, L., Petrosino, P., Alberico, I., and Postiglione, I., 2001, Long term volcanic
hazard forecast based on Somma-Vesuvio past eruptive activity: Bulletin
of Volcanology, v. 68, p. 145–163.
Lowe, D.R., Williams, S.N., Leigh, E., Connor, C.C., Gemmell, J.B., and Stoiber,
R.E., 1986, Lahars initiated by the 13 November 1985 eruption of Nevado
del Ruiz, Colombia: Nature, v. 324, p. 51–53, doi: 10.1038/324051a0.
Macedonio, G., and Pareschi, M.T., 1992, Numerical simulation of some lahars
from Mount St. Helens: Journal of Volcanology and Geothermal Research,
v. 54, p. 65–80, doi: 10.1016/0377-0273(92)90115-T.
Major, J.J., 1997, Depositional processes in large-scale debris fl ow experiments:
Journal of Geology, v. 105, p. 345–366.
Major, J.J., 1998, Pebble orientation on large, experimental debris-fl ow deposits:
Sedimentary Geology, v. 117, p. 151–164, doi: 10.1016/S0037-
0738(98)00014-1.
Major, J.J., and Iverson, R.M., 1999, Debris-fl ow deposition: Effect of porefl
uid pressure and friction concentrated at fl ow margins: Geological
Society of America Bulletin, v. 111, p. 1424–1434, doi: 10.1130/0016-
7606(1999)111<1424:DFDEOP>2.3.CO;2.
Mastin, L.J., and Witter, J.B., 2000, The hazard of eruptions through lakes
and seawater: Journal of Volcanology and Geothermal Research, v. 97,
p. 195–214, doi: 10.1016/S0377-0273(99)00174-2.
Miall, A.D., 1978, Lithofacies types and vertical profi le models in braided river
deposits: A summary, in Miall, A.D., ed., Fluvial Sedimentology: Canadian
Society of Petrology and Geology Memoire, p. 597–604.
Mizuyama, T., Kobashi, S., and Ou, G., 1992, Prediction of debris fl ow peak
discharge: Proceedings International Symposium Interpraevent, Bern,
v. 4, p. 99–108.
Newhall, C.G., and Punongbayan, R.S., eds., 1996, Fire and mud: Eruption and
lahars of Mount Pinatubo, Philippines: Seattle and London, PHIVOLCS,
Quezon City and University of Washington Press, p. 1126.
Onorati, G., Braca, G., and Iritano, G., 1999, Evento idrogeologico del 4, 5 e 6
maggio 1998 in Campania: Monitoraggio e analisi idrologica: Atti della
Accademia Nazionale dei Lincei, v. 154, p. 103–108.
Pareschi, M.T., Favalli, M., Giannini, F., Sulpizio, R., Zanchetta, G., and Santacroce,
R., 2000a, May 5, 1998, debris fl ows in circumvesuvian areas
(southern Italy): Insights for hazard assessment: Geology, v. 28, p. 639–
642, doi: 10.1130/0091-7613(2000)028<0639:MDFICV>2.3.CO;2.
Pareschi, M.T., Santacroce, R., Favalli, M., Giannini, F., Bisson, M., Meriggi,
A., and Cavarra, L., 2000b, Un GIS per il Vesuvio: Pisa, Felici Editore,
p. 47.
Pareschi, M.T., Santacroce, R., Sulpizio, R., and Zanchetta, G., 2002a, The volcaniclastic
mass fl ow hazard related to the remobilization of fallout deposits
in southern Campania, Italy: Explosive volcanism in subduction zones,
Mount Pelée, Martinique, 12–16 May 2002, abstract volume, p. 87.
Pareschi, M.T., Santacroce, R., Sulpizio, R., and Zanchetta, G., 2002b, Volcaniclastic
debris fl ows in the Clanio Valley (Campania, Italy): Insights for the
assessment of hazard potential: Geomorphology, v. 43, p. 219–231, doi:
10.1016/S0169-555X(01)00134-9.
Pierson, T.C., 1981, Dominant particle support mechanisms in debris fl ows at
Mt. Thomas, New Zealand, and implication for fl ow mobility: Sedimentology,
v. 28, p. 49–60.
Pierson, T.C., 1985, Initiation and fl ow behavior of the 1980 Pine Creek
and Muddy River lahars, Mt. St. Helens, Washington: Geological
Society of America Bulletin, v. 96, p. 1056–1069, doi: 10.1130/0016-
7606(1985)96<1056:IAFBOT>2.0.CO;2.
Pierson, T.C., 1995, Flow characteristic of large eruption-triggered debris
fl ows at snow-clad volcanoes: Constraints for debris-fl ow models: nal of Volcanology and Geothermal Research, v. 66, p. 283–294, doi:
10.1016/0377-0273(94)00070-W.
Pierson, T.C., 1998, An empirical method for estimating travel times for wet
volcanic mass fl ows: Bulletin of Volcanology, v. 60, p. 98–109, doi:
10.1007/s004450050219.
Pierson, T.C., and Costa, J.E., 1987, A rheological classifi cation of subaerial
sediment-water fl ow: Geological Society of America: Reviews in Engineering
Geology, v. 7, p. 1–12.
Pierson, T.C., and Scott, K.M., 1985, Downstream dilution of a lahar: Transition
from debris fl ow to hyperconcentrated streamfl ow: Water Resources
Research, v. 21, p. 1511–1524.
Reid, M.E., and Iverson, R.M., 1992, Gravity-driven groundwater fl ow and
slope failure potential 2: Effects of slope morphology, material properties
and hydraulic heterogeneity: Water Resources Research, v. 28, p. 939–
950, doi: 10.1029/91WR02695.
Rickenmann, D., 1999, Empirical relationships for debris fl ows: Natural Hazards,
v. 19, p. 47–77, doi: 10.1023/A:1008064220727.
Rodolfo, K.S., and Arguden, A.T., 1991, Rain-lahar generation and sedimentdelivery
systems at Mayon volcano, Philippines, in Fisher, R.V., and Smith,
G.A., eds., Sedimentation in volcanic settings: Society of Economic Paleontologists
and Mineralogists Special Publication 45, p. 71–87.
Rosi, M., and Santacroce, R., 1983, The A.D. 472 “Pollena” eruption: Volcanological
and petrological data for this poorly known Plinian-type event
at Vesuvius: Journal of Volcanology and Geothermal Research, v. 17,
p. 249–271, doi: 10.1016/0377-0273(83)90071-9.
Rosi, M., Principe, C., and Vecci, R., 1993, The 1631 eruption of Vesuvius
reconstructed from the review of chronicles and study of deposits: Journal
of Volcanology and Geothermal Research, v. 58, p. 151–182, doi:
10.1016/0377-0273(93)90106-2.
Santacroce, R., ed., 1987, Somma-Vesuvius: Consiglio Nazionale delle Ricerche
(CNR), Quaderni della Ricerca Scientifi ca, v. 114, 220 .
Santacroce, R., Andronico, D., Cavarra, L., Cioni, R., Favalli, M., Longo, A.,
Macedonio, G., Pareschi, M.T., Sbrana, A., Sulpizio, R., and Zanchetta,
G., 1998, Updating the scenario of the mid-term maximum expected eruption
of Vesuvius [Abstract]: Cities on volcanoes, International meeting:
Roma e Napoli 28 Giugno 4 Luglio 1998, Naples, Osservatorio Vesuviano,
p. 119.
Scott, K.M., 1989, Magnitude and frequency of lahars and lahar-runout fl ows
in the Toutle-Cowlitz River System: U. S. Geological Survey Professional
Paper 1447-B, p. 1–33.
Scott, K.M., Vallance, J.W., and Pringle, P.T., 1995, Sedimentology, behavior,
and hazard of debris fl ows at Mount Rainer, Washington: U. S. Geological
Survey Professional Paper 1547, p. 1–56.
Scott, K.M., Macías, J.L., Naranjo, J.A., Rodríguez, S., and McGeehin, J.P.,
2001, Catastrophic debris fl ows transformed from landslides in volcanic
terrains: Mobility, hazard assessment and mitigation strategies: U. S.
Geological Survey Professional Paper 1630, p. 1–59.
Sheridan, M.F., Bonnard, C., Carreño, R., Siebe, C., Strauch, W., Navarro, M.,
Calero, J.C., and Trujilo, N.B., 1999, 30 October 1998 rock fall/avalanche
and breakout fl ow of Casita Volcano, Nicaragua, triggered by hurricane
Mitch: Landslide News, v. 12, p. 2–4.
Siebe, C., Schaaf, P., and Urrutia-Fucugauchi, J., 1999, Mammoth bones embedded
in a late Pleistocene lahar from Popocatépetl volcano, near Tocuila,
central Mexico: Geological Society of America Bulletin, v. 111, p. 1550–
1567, doi: 10.1130/0016-7606(1999)111<1550:MBEIAL>2.3.CO;2.
Sigurdsson, H., Carey, S., Cornell, W., and Pescatore, T., 1985, The eruption
of Vesuvius in A.D. 79: National Geographic Research, v. 91, p. 12,539–
12,571.
Smith, G.A., 1986, Coarse-grained non-marine volcaniclastic sediment: Terminology
and depositional process: Geological Society of America Bulletin,
v. 97, p. 1–10, doi: 10.1130/0016-7606(1986)97<1:CNVSTA>2.0.CO;2.
Smith, G.A., 1987, The infl uence of explosive volcanism on fl uvial sedimentation:
The Deschutes formation (Neogene) in central Oregon: Journal of
Sedimentary Petrology, v. 57, p. 613–629.
Smith, G.A., and Fritz, W.J., 1989, Volcanic infl uences on terrestrial sedimentation:
Geology, v. 17, p. 375–376, doi: 10.1130/0091-7613(1989)017<0375:
VIOTS>2.3.CO;2.
Smith, G.A., and Lowe, D.R., 1991, Lahars: Volcano-hydrologic events and
deposition in the debris fl ow–hyperconcentrated fl ow continuum, in
Fisher, R.V., and Smith, G.A., eds., Sedimentation in volcanic settings:
Society of Economic Paleontologists and Mineralogists Special Publication
45, p. 59–70.
Smith, R.D., and Swanson, F.J., 1987, Sediment routing in a small drainage
basin in the blast zone at Mount St. Helens, Washington, U.S.A.: Geomorphology,
v. 1, p. 1–13, doi: 10.1016/0169-555X(87)90003-1.
Sohn, Y.K., 2000, Coarse-grained debris-fl ow deposits in the Miocene fan deltas
SE Korea: A scaling analysis: Sedimentary Geology, v. 130, p. 45–64,
doi: 10.1016/S0037-0738(99)00099-8.
Sohn, Y.K., Rhee, C.W., and Kim, B.C., 1999, Debris fl ow and hyperconcentrated
fl ood-fl ow deposits in an alluvial fan, northwestern part of the
Cretaceous Yongdon Basin, Central Korea: Journal of Geology, v. 107,
p. 111–132, doi: 10.1086/314334.
Sulpizio, R., Di Vito, M.A., and Zanchetta, G., 2000, Landscape response to
the deposition of airfall pyroclastics from large explosive eruptions: an
example from the Campanian area (southern Italy): Physics and Chemistry
of the Earth, v. 9-11, p. 759–762.
Sulpizio, R., Mele, D., Dellino, P., and La Volpe, L., 2005, A complex, subplinian-
type eruption from low-viscosity, phonolitic to tephri-phonolitic
magma: The AD 472 (Pollena) eruption of Somma-Vesuvius (Italy): Bulletin
of Volcanology, v. 67, p. 743–767, doi: 10.1007/s00445-005-0414-x.
Vallance, J.W., and Scott, K.M., 1997, The Osceola mudfl ow from Mount
Rainer: Sedimentology and hazards implications of a huge clay-rich
debris fl ow: Geological Society of America Bulletin, v. 109, p. 143–163,
doi: 10.1130/0016-7606(1997)109<0143:TOMFMR>2.3.CO;2.
Waitt, R.B., Pierson, T.C., MacLeod, N.S., Janda, R.J., Voight, B., and Holcomb,
R.T., 1983, Eruption-triggered avalanche, fl ood, and lahar at Mount
St. Helens—Effect of winter snowpack: Science, v. 221, p. 1393–1397.
White, J.D.L., Houghton, B.F., Hodgson, K.A., and Wilson, C.J.N., 1997,
Delayed sedimentary response to the A.D. 1886 eruption of Tarawera,
New Zealand: Geology, v. 25, p. 459–462, doi: 10.1130/0091-
7613(1997)025<0459:DSRTTA>2.3.CO;2.
Zanchetta, G., Sulpizio, R., Pareschi, M.T., Leoni, F.M., and Santacroce, R.,
2004a, Characteristics of May 5–6, 1998 volcaniclastic debris fl ows in
the Sarno areas (Campania, southern Italy): Relationships to structural
damage and hazard zonation: Journal of Volcanology and Geothermal
Research, v. 133, p. 377–393, doi: 10.1016/S0377-0273(03)00409-8.
Zanchetta, G., Sulpizio, R., and Di Vito, M.A., 2004b, The role of volcanic
activity and climate in alluvial fan growth at volcanic areas: An example
from southern Campania (Italy): Sedimentary Geology, v. 168, p. 249–
280, doi: 10.1016/j.sedgeo.2004.04.001.