The Carrara marble quarries (Apuan Alps, north-western Tuscany) are among the most famous in the world and nowadays are also a tourist resource. In time, the intense quarrying formed wide and thick dumps of waste block and pebble material (locally named ravaneti), representing a typical landscape of the Apuan area. Nowadays, a great amount of quarry dumps lies on steep slopes and invades many valley bottoms, where usually there is only underground water flow, without any superficial flow. During rainstorms, the water level may quickly rise to a significant runoff. This often causes floods, landslides and debris flows, as recently occurred on September 23, 2003. In such a context, this research aimed at determining the triggering conditions of the instability phenomena involving quarry waste. In particular, three quarry dumps were selected in the Torano basin (upstream of Carrara). At first, the spatial and morphological evolution of the dumps was studied, trying to understand also the different grain size of the material accumulated in time; then, a detailed geomorphologic analysis was performed, individuating several areas with different characteristics (quarry activity, instability phenomena, debris flow prone areas, land use, etc). Finally, many grain size analyses were carried out in the three quarry dumps. The wide heterogeneity of the grain size needed two methodologies: the coarse fraction (blocks and pebbles) was analysed by means of image analysis, while the finer material (gravel, sand, silt and clay) was analysed in laboratory. The research is clearly in progress, nevertheless represents a first important step to individuate the triggering factors of debris flow phenomena in quarry dumps. In fact, the hazard estimation of the quarry areas is extremely important: for protecting quarrymen and quarrying activity, for the safety of the densely populated areas downstream and for protecting and appreciating the tourist appeal.
Evolution and characterization of the quarry waste in relation to slope stability: preliminary evaluation in the Carrara marble basin (Italy)
D'AMATO AVANZI, GIACOMO ALFREDO;GIANNECCHINI, ROBERTO;
2005-01-01
Abstract
The Carrara marble quarries (Apuan Alps, north-western Tuscany) are among the most famous in the world and nowadays are also a tourist resource. In time, the intense quarrying formed wide and thick dumps of waste block and pebble material (locally named ravaneti), representing a typical landscape of the Apuan area. Nowadays, a great amount of quarry dumps lies on steep slopes and invades many valley bottoms, where usually there is only underground water flow, without any superficial flow. During rainstorms, the water level may quickly rise to a significant runoff. This often causes floods, landslides and debris flows, as recently occurred on September 23, 2003. In such a context, this research aimed at determining the triggering conditions of the instability phenomena involving quarry waste. In particular, three quarry dumps were selected in the Torano basin (upstream of Carrara). At first, the spatial and morphological evolution of the dumps was studied, trying to understand also the different grain size of the material accumulated in time; then, a detailed geomorphologic analysis was performed, individuating several areas with different characteristics (quarry activity, instability phenomena, debris flow prone areas, land use, etc). Finally, many grain size analyses were carried out in the three quarry dumps. The wide heterogeneity of the grain size needed two methodologies: the coarse fraction (blocks and pebbles) was analysed by means of image analysis, while the finer material (gravel, sand, silt and clay) was analysed in laboratory. The research is clearly in progress, nevertheless represents a first important step to individuate the triggering factors of debris flow phenomena in quarry dumps. In fact, the hazard estimation of the quarry areas is extremely important: for protecting quarrymen and quarrying activity, for the safety of the densely populated areas downstream and for protecting and appreciating the tourist appeal.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
