The mobility of some debris flows in pyroclastic deposits of the northwestern Campanian region (southern Italy)

Abstract. On 15–16 December 1999, heavy rainfall severely stroke Campania region (southern Italy), triggering numerous debris flows on the slopes of the San Martino Valle Caudina-Cervinara area. Soil slips originated within the weathered volcaniclastic mantle of soil cover overlying the carbonate skeleton of the massif. Debris slides turned into fast flowing mixtures of matrix and large blocks, downslope eroding the soil cover and increasing their original volume. At the base of the slopes, debris flows impacted on the urban areas, causing victims and severe destruction (Vittori et al., 2000). Starting from a recent study on landslide risk conditions in Campania, carried out by the Regional Authority (PAI –Hydrogeological setting plan, in press), an evaluation of the debris-flow susceptibility has been performed for selected areas of the above mentioned villages. According to that study, such zones would be in fact characterised by the highest risk levels within the administrative boundaries of the same villages ("HR-zones"). Our susceptibility analysis has been performed by applying SCIDDICA S3–hex – a hexagonal Cellular Automata model (von Neumann, 1966), specifically developed for simulating the spatial evolution of debris flows (Iovine et al., 2002). In order to apply the model to a given study area, detailed topographic data and a map of the erodable soil cover overlying the bedrock of the massif must be provided (as input matrices); moreover, extent and location of landslide source must also be given. Real landslides, selected among those triggered on winter 1999, have first been utilised for calibrating SCIDDICA S3–hex and for defining "optimal" values for parameters. Calibration has been carried out with a GIS tool, by quantitatively comparing simulations with actual cases: optimal values correspond to best simulations. Through geological evaluations, source locations of new phenomena have then been hypothesised within the HR-zones. Initial volume for these new cases has been estimated by considering the actual statistics of the 1999 landslides. Finally, by merging the results of simulations, a deterministic susceptibility zonation of the considered area has been obtained. In this paper, aiming at illustrating the potential for debris-flow hazard analyses of the model SCIDDICA S3–hex, a methodological example of susceptibility zonation of the Vallicelle HR-zone is presented.

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Seasonal effects of rainfall on the shallow pyroclastic deposits of the Campania region (southern Italy)

Landslides ◽

10.1007/s10346-013-0395-3 ◽

2013 ◽

Vol 11 (5) ◽

pp. 779-792 ◽

Cited By ~ 61

Author(s):

Leonardo Cascini ◽

Giuseppe Sorbino ◽

Sabatino Cuomo ◽

Settimio Ferlisi

Keyword(s):

Southern Italy ◽

Seasonal Effects ◽

Pyroclastic Deposits ◽

Campania Region

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The remarkable volcanism of Shastina, a stratocone segment of Mount Shasta, California

Geosphere ◽

10.1130/ges02080.1 ◽

2020 ◽

Vol 16 (5) ◽

pp. 1153-1178

Author(s):

Robert L. Christiansen ◽

Andrew T. Calvert ◽

Duane E. Champion ◽

Cynthia A. Gardner ◽

Judith E. Fierstein ◽

...

Keyword(s):

Debris Flows ◽

Crustal Contamination ◽

Liquid Composition ◽

Pyroclastic Flows ◽

The West ◽

Pyroclastic Deposits ◽

North Side ◽

Eruptive Episode ◽

Central Crater ◽

Nearly Continuous

Abstract Mount Shasta, a 400 km3 volcano in northern California (United States), is the most voluminous stratocone of the Cascade arc. Most Mount Shasta lavas vented at or near the present summit; relatively smaller volumes erupted from scattered vents on the volcano’s flanks. An apron of pyroclastic and debris flows surrounds it. Shastina, a large and distinct cone on the west side of Mount Shasta, represents a brief but exceptionally vigorous period of eruptive activity. Its volume of ∼13.5 km3 would make Shastina itself one of the larger Holocene Cascade stratovolcanoes. Its andesite-dacite lavas average 63 wt% SiO2 and have little compositional or petrographic variation; they erupted almost entirely from one central vent, although a single vent below Shastina’s north side erupted a flow of the same composition. Eruptions ended with explosive enlargement and breaching of the central crater and successive emplacement of four, more-silicic dacite domes within the crater and pyroclastic flows down its flank. Black Butte, a large volcanic dome and pyroclastic complex below the west flank of Shastina, is petrographically and chemically distinct but only slightly younger than Shastina itself, part of a nearly continuous Shastina–Black Butte eruptive episode. Shastina overlies the widespread pumice of Red Banks, erupted from the Mount Shasta summit area and 14C dated at ca. 10,900 yr B.P. (calibrated). Shastina and Black Butte pyroclastic deposits have calibrated 14C ages indistinguishable from one another at ca. 10,700 cal. yr B.P. A cognate granitic-textured inclusion in a late Shastina lava flow yields a 238U-230Th date on zircons within error of those ages. Our conclusion that the entire, voluminous Shastina–Black Butte episode lasted no more than a few hundred years is confirmed by almost identical remanent magnetic directions of all of the lavas and pyroclastic deposits. Although extremely similar, the remanent magnetic directions do reveal a short path of secular variation through the eruptive sequence. We conclude that the entire Shastina–Black Butte eruptive episode lasted no more than ∼200 yr. The magmas that produced the Shastina and Black Butte eruptions were separate individual bodies at different crustal levels. Each of these eruptive sequences probably represents magma approximating a liquid composition that experienced only minimal differentiation or crustal contamination and remained separated from the main central conduit for most eruptions of Mount Shasta. The probability of another rapidly developing, brief but voluminous eruptive episode at Mount Shasta is low but should not be ignored in evaluating future possible eruptive hazards.

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Effect of antecedent-hydrological conditions on rainfall triggering of debris flows in ash-fall pyroclastic mantled slopes of Campania (southern Italy)

Landslides ◽

10.1007/s10346-015-0647-5 ◽

2015 ◽

Vol 13 (5) ◽

pp. 967-983 ◽

Cited By ~ 47

Author(s):

E. Napolitano ◽

F. Fusco ◽

R. L. Baum ◽

J. W. Godt ◽

P. De Vita

Keyword(s):

Debris Flows ◽

Southern Italy ◽

Hydrological Conditions ◽

Ash Fall

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Magnetic fabric investigations of pyroclastic deposits from Phlegrean Fields, southern Italy

Nature ◽

10.1038/306461a0 ◽

1983 ◽

Vol 306 (5942) ◽

pp. 461-463 ◽

Cited By ~ 38

Author(s):

A. Incoronato ◽

F. T. Addison ◽

D. H. Tarling ◽

G. Nardi ◽

T. Pescatore

Keyword(s):

Southern Italy ◽

Magnetic Fabric ◽

Pyroclastic Deposits ◽

Phlegrean Fields

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Multiple Effects of Intense Meteorological Events in the Benevento Province, Southern Italy

Water ◽

10.3390/w11081560 ◽

2019 ◽

Vol 11 (8) ◽

pp. 1560 ◽

Cited By ~ 3

Author(s):

Paola Revellino ◽

Luigi Guerriero ◽

Neri Mascellaro ◽

Francesco Fiorillo ◽

Gerardo Grelle ◽

...

Keyword(s):

Soil Erosion ◽

Debris Flows ◽

Southern Italy ◽

Statistical Characteristics ◽

Total Rainfall ◽

Campania Region ◽

Rainfall Events ◽

Pattern Distribution ◽

The Town ◽

Flooded Areas

In October 2015, two intense rainfall events hit the central and southern regions of Italy and triggered a combination of different and widespread effects, including floods, landslides, and soil erosion. These outcomes devastated about 68 municipalities of the Benevento province (Campania region), killed two people, and caused millions of euros worth of damage to structures, infrastructures, and agriculture. The town of Benevento was one of the sectors most affected by overflow. Extensive areas characterized by flyschoid outcrops experienced widespread occurrences of soil erosion and landslides, and destructive, high-velocity debris flows (about 50) afflicted areas that had experienced heavy rainfall of higher intensity (total rainfall of 415.6 mm). In this study, the characteristics of these rainfall events and related geomorphological processes were determined by (i) analyzing the available rainfall data to identify the spatial pattern, distribution, and statistical characteristics of the two storms and (ii) mapping the storm effects, such as flooded areas, landslide types, and soil erosion. These effects were then related to the spatial distribution of the storms and the local geological and geomorphologic settings that drove their initiation and development.

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