Landslides, floods and sinkholes in a karst environment: the 1–6 September 2014 Gargano event, southern Italy

Abstract. In karst environments, heavy rainfall is known to cause multiple geohydrological hazards, including inundations, flash floods, landslides and sinkholes. We studied a period of intense rainfall from 1 to 6 September 2014 in the Gargano Promontory, a karst area in Puglia, southern Italy. In the period, a sequence of torrential rainfall events caused severe damage and claimed two fatalities. The amount and accuracy of the geographical and temporal information varied for the different hazards. The temporal information was most accurate for the inundation caused by a major river, less accurate for flash floods caused by minor torrents and even less accurate for landslides. For sinkholes, only generic information on the period of occurrence of the failures was available. Our analysis revealed that in the promontory, rainfall-driven hazards occurred in response to extreme meteorological conditions and that the karst landscape responded to the torrential rainfall with a threshold behaviour. We exploited the rainfall and the landslide information to design the new ensemble–non-exceedance probability (E-NEP) algorithm for the quantitative evaluation of the possible occurrence of rainfall-induced landslides and of related geohydrological hazards. The ensemble of the metrics produced by the E-NEP algorithm provided better diagnostics than the single metrics often used for landslide forecasting, including rainfall duration, cumulated rainfall and rainfall intensity. We expect that the E-NEP algorithm will be useful for landslide early warning in karst areas and in other similar environments. We acknowledge that further tests are needed to evaluate the algorithm in different meteorological, geological and physiographical settings.

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Landslides, floods and sinkholes in a karst environment: the 1–6 September 2014 Gargano event, southern Italy

10.5194/nhess-2016-310 ◽

2016 ◽

Author(s):

Maria Elena Martinotti ◽

Luca Pisano ◽

Ivan Marchesini ◽

Mauro Rossi ◽

Silvia Peruccacci ◽

...

Keyword(s):

Southern Italy ◽

Flash Floods ◽

Temporal Information ◽

Exceedance Probability ◽

Karst Environment ◽

Karst Landscape ◽

Hydrological Hazards ◽

Gargano Promontory ◽

Landslide Forecasting ◽

Torrential Rainfall

Abstract. In karst environments, heavy rainfall is known to cause multiple geo-hydrological hazards, including inundations, flash floods, landslides, and sinkholes. We studied a period of intense rainfall from 1 to 6 September 2014 in the Gargano Promontory, a karst landscape in Puglia, southern Italy. In the period, a sequence of torrential rainfall events caused severe damage, and claimed two fatalities, triggering different types of geo-hydrological hazards. The amount and accuracy of the geographical and the temporal information varied for the different hazards. The temporal information was most accurate for the inundation caused by a major river, less accurate for flash floods caused by minor torrents, and even less accurate for landslides. For sinkholes, only generic information on the period of occurrence of the failures was available. Our analysis revealed that in the Promontory, rainfall-driven geo-hydrological hazards occurred in response to extreme meteorological conditions, and that the karst landscape responded to the torrential rainfall with a threshold behaviour. We exploited the rainfall and the landslide information to design the new Ensemble – Non Exceedance Probability, E-NEP algorithm for the quantitative evaluation of the possible occurrence of rainfall-induced landslides, and of related geo-hydrological hazards. The ensemble of the metrics produced by the E-NEP algorithm provided better diagnostics than the single metrics often used for landslide forecasting, including rainfall duration, cumulated rainfall and rainfall intensity. We expect that the E-NEP algorithm will be useful for landslide early warning in karst areas and in other similar environments. We acknowledge that further tests are needed to evaluate the algorithm in different meteorological, geological, and physiographical settings.

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Flood history in the karst environment of Castellana-Grotte (Apulia, southern Italy)

Natural Hazards and Earth System Science ◽

10.5194/nhess-3-593-2003 ◽

2003 ◽

Vol 3 (6) ◽

pp. 593-604 ◽

Cited By ~ 20

Author(s):

M. Parise

Keyword(s):

Rock Mass ◽

Complex Network ◽

Critical Analysis ◽

Southern Italy ◽

Karst Area ◽

Flood Events ◽

Karst Environment ◽

Main Factors ◽

The Town

Abstract. Karst environments are characterized by peculiar hydrologic features, and in particular by a very limited, if not absent, surface hydrography. Water tends to infiltrate rapidly underground through the complex network of fractures and karstic conduits in the rock mass. However, on the occasion of concentrated rainfall, as well as in case of prolonged precipitation, such network might not be able to allow flowing of large amounts of water, which causes the occurrence of floods. This contribution illustrates the flood history in a classical karst area of Southern Italy, the town of Castellana-Grotte, in Apulia. The oldest part of the town lies at the bottom of a karst valley, which was hit by many flood events in the last centuries. More than twenty of these are here documented, starting from critical analysis of existing publications and documents, integrated with additional historical researches. Aimed at reconstructing the flood history at Castellana-Grotte, the best-documented events are described, together with the main factors, which played a role in distribution and gravity of the related damage. Eventually some engineering works realized during the first decades of the last century, in order to avoid further damage on the occasion of catastrophic floods, are also described.

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TIMING AND CAUSES OF THE DROWNING AND BACK STEP OF THE APULIA CARBONATE PLATFORM (MONTE SACRO SEQUENCE, GARGANO PROMONTORY, SOUTHERN ITALY)

10.1130/abs/2019am-330972 ◽

2019 ◽

Author(s):

Katherine Jones ◽

◽

Daniel J. Lehrmann ◽

Michele Morsilli ◽

Khalid Al-Ramadan ◽

...

Keyword(s):

Southern Italy ◽

Carbonate Platform ◽

Gargano Promontory

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Mineralogical and Geochemical Features of Cretaceous Bauxite from San Giovanni Rotondo (Apulia, Southern Italy): A Provenance Tool

Minerals ◽

10.3390/min8120567 ◽

2018 ◽

Vol 8 (12) ◽

pp. 567 ◽

Cited By ~ 1

Author(s):

Rosa Sinisi

Keyword(s):

Rare Earth ◽

Southern Italy ◽

Dilution Effect ◽

Source Material ◽

Detrital Zircons ◽

Chemical Compositions ◽

Geochemical Proxies ◽

Mineral Phases ◽

Gargano Promontory ◽

Parental Material

In this study, the mineralogical and chemical compositions of bauxite from San Giovanni Rotondo (SGR) on the Gargano Promontory (northern Apulia, Italy) are presented and discussed with the aim of assessing the nature of its source material. Bauxite from the SGR, which is known as the “Montecatini mine”, was exploited intensively until the 1970s to recover alumina. As with most of the autochthonous peri-Mediterranean bauxites, the studied deposit is a karst bauxite with a massive, matrix-supported texture and an oolitic structure. Boehmite and hematite are the main mineral phases, and anatase, rutile, and kaolinite are present in lesser amounts along with detrital zircons and monazite grains. Calcite is abundant only in the deposit’s lower portion, triggering a significant dilution effect on trace element concentrations. However, with respect to the average crust and chondrite compositions, strong enrichments of trace metals (up to 10X Upper Continental Crust’s (UCC)) and rare earth elements (REEs, up to 800X chondrite) exist throughout the studied deposit. The distribution of REEs, the (La/Yb)N and Eu/Eu* ratios, and an Eu/Eu* versus Sm/Nd diagram have been used for determining the bauxite’s provenance. These geochemical proxies point to a parental material consisting of a mixture of distant magmatic and siliciclastic components.

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