TORRENTIAL DEPOSITS OF SOUTHERN ITALY 



291 



FlGl'RE 



■Type of Cross-bedding. 



Observed in the torrential deposits near 

 Pontegrande, in Calabria. 



slopes are often found the steep pinnacles with pebble cappings so charac- 

 teristic of rain erosion. Other deposits and erosional forms were ob- 

 served about Taormina and are well shown from the summit of Mola. 



In the summer season the "fiumare" are dry, the pebble floors being 

 generally utilized as highways of travel ; but after the rains they become 

 roaring torrents, which suddenly rise and as suddenly subside. At Co- 

 senza, in Calabria, the writer was fortunate in witnessing the trans- 

 formation of the Busento (the ancient Buxentius) by one of the sudden 



cloudbursts characteristic of the 

 region. Crossing the river by the 

 famous Ponte Alarico in the face 

 of an impending shower, the 

 broad river floor showed a mere 

 thread of water. When the storm 

 had burst the steeply sloping 

 Corso of the city became trans- 

 formed into a swift current bor- 

 dered by waterfalls where the 

 steep side streets entered. Within 

 a half hour the storm had passed, 

 but the Busento was swollen to a 

 roaring torrent which filled its bed from bank to bank. A few hours later 

 it presented almost the same appearance as before the rain. 



All about Cosenza are found torrential deposits, including round peb- 

 bles and boulders, not unlike the Alhambra conglomerate of Granada. 

 Nearly identical deposits were studied at Eossano and at Pontegrande, 

 near Catanzaro, in Calabria. At the last mentioned locality the deposits 

 can be little short of 1,500 feet in thickness, if they do not exceed that 

 figure. The boulders included are of many petrographic types and often 

 exceed a foot in diameter. Between markedly horizontal layers revealed 

 by the finer material, cross-bedding of a type often seen in ancient sand- 

 stones is well displayed (figure 2). In this type we find between thick 

 horizontal layers intercalated beds in which the bedding makes a nearly 

 uniform but relatively large angle with the layers which inclose it. 



At Rossano the torrential deposits are locally faulted in the manner 

 shown in figure 3. Through these deposits the crystalline formations 

 occasionally project on steep walls. High up the valleys toward the 

 crests of the older rocks the generally horizontal bedding is locally re- 

 placed by steeply dipping layers, which, like those observed in Granada, 

 incline toward the valley. Angles as high as 45 degrees have been ob- 

 served. Where deep dissection has been produced by the "fiumare," the 

 steep walls of loosely compacted material become during the rainy season 



