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Earth of fire

Actualité volcanique, Articles de fond sur étude de volcan, tectonique, récits et photos de voyage

Sardinia is home to some unknown volcanic landscapes ... among them , the center of the village of Guspini has a small neck (*) twenty meters height.

Guspini - parco G.Dessi
                      Sardinia / Italy - neck of Guspini - Photo G. Parco Dessi

This place was first used as a quarry , then closed and purchased by the local authority in 2004 for the recovery . A sum of € 100,000 was used to expropriation and the work of clearing and cleaning of the wall , which began in 2010.

basalti colonnari guspini - provincia.mediocampidano            
Sardinia / Italy - neck Guspini , detail - Photo Provincia MédioCampidano

This alkaline neck consists of hawaiite, a variety of trachybasalt, which outcrops on the west branch of the graben Campidano intruded into the Ordovician sandstones . This outcrop is characterized by the presence of millimetric to centimetric fragments of the Earth's mantle . ( Lustrino et al. 2004)

Graben Campidano - Marmilla las plassas - Cristiano Cani              
Sardinia - Landscape of the Graben Campidano - Photo Christiano Cani

Dating refers to the Plio- Pleistocene volcanism, in the vicinity of there 3 million years .

Unlike volcanic rocks of the Oligo - Miocene that outcrops only the west side of the island, the volcanic activity of Plio -Pleistocene concerns areas located east and west of Sardinia.

This magmatism was developed after a hiatus of about 10 Ma after the previous orogenic magmatism , it is located mainly along faults related to the opening of the basin of the Tyrrhenian Sea.
The Graben Campidano which intersects the southwest part of the island shows tensile stresses during the geodynamic evolution of the western Mediterranean.

  Volcanic and sedimentary rocks of Sardinia - Location relative to other Italian- Sicilian volcanoes
       Graben campidano going diagonally from Capo Ferrato to Tharros / Montiferro .

Sketch map of the geology of southern Sardinia showing loca
Sketch map of the geology of southern Sardinia showing loca Geological Map of South Sardinia with the position of the Graben campidano - doc . H.Downes

(*) Neck: magmatic intrusions characterized by radial prismation resulting from old volcanic vents filled and exposed by erosion.



Sources :

- The role of lower continental crust and lithospheric mantle in the genesis of Plio-Pleistocene volcanic rocks from Sardinia - By M.Lustrino & al.

- European subcontinental mantle as related by neogene volcanic rocks and mantle xenoliths of Sardinia - by M.Lustrino & al.

- La dérive Corso-Sarde - vidéo


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