Argentarola Island, Monte Argentario, Grosseto Province, Tuscany, Italyi

Regional Level Types
Argentarola Island	Island
Monte Argentario	Commune
Grosseto Province	Province
Tuscany	Region
Italy	Country

Argentarola Island, located near the Argentario Promontory, is made up of a grey, stratified dolomitic limestone bedrock (Upper Triassic) with intercalated slates. It is an islet (about 200x75 m, and 50 m in height) and has an asymmetric shape: on its western coast, there is a subvertical cliff that descends abruptly to 50 m below sea level, while the eastern side follows the limestone stratification and represents the upper part of a monoclinal structure, with layers dipping 45° to NNW.

Pelagosite as black varnish-like concretions on littoral rocks has been described by Clerici (1913). The same mineral substance was already observed by Santi (1798), who regarded it as a wave-deposited mixture of calcium carbonate and black iron oxide.

The Argentarola Cave (Grotta dell'Argentarola), which is currently flooded by the Mediterranean Sea, is located on the southern side of the islet. The entrance of the cave (-6 m) is composed of a long narrow tunnel leading down into a wide chamber that reaches a water depth of -20 m, a second narrow tunnel is presently filled by clay at -28 m. The connection with the sea is provided by a tunnel (filled with sand after few meters) recently discovered out of the cave at -29.7 m. The narrow entrance has acted to extinguish energy during the Middle and Late Pleistocene, thus contributing to the preservation of thousands of calcite speleothems. The cave continues into a large room with abundant stalagmites and stalactites on the walls of both the main and the secondary holes. The total length of the cave, with all its passages, is about 90 m, while the total surface area (calculated in a central section) is 720 m2.
Calcite speleothems consist of a sequence of continental layers and marine biogenic overgrowths (serpulid colonies). Continental layers grew during lowstand periods and marine layers (formed by serpulid, i.e. the marine worm Serpula massiliensis) were deposited during highstand periods. The composite sequence, testifying several Quaternary sea-level changes, contains five marine and four continental layers, formed over the last 215 ka.

Fossils

This region is too big or complex to display the fossil list, try looking at smaller subregions.

Other Databases

Wikidata ID:	Q1817383

References