Originariamente inviato da: piombino
(non mi chiedere il perchè delle frecce, grazie ti_prego )


Manca solo una freccia: quella che rappresenterebbe le varie trascorrenze in testa alla subduzione, che puntano sul rhodes-basin.

Io la metterei come risultante (le trascorrenze puntano a ENE, mentre il rhodes-basin sembra elevato da una spinta proveniente da S pieno), che punta verso NE.

Aggiunta l'ultima freccia, la girandola è completa.......





Ho trovato un articoletto che parla dei vulcani di fango....

Se non ho male interpretato, dice che la compressione nel prisma d'accrezione ha generato i vulcani a S di Creta, ma una tua "benedizione" mi è assai gradita....

Quote:
Mud volcanism was initiated when overpressured muds rose through the Mediterranean Ridge accretionary prism. Early
mud volcanism was marked by eruption of coarse clastic sediments forming small cones of debris flow deposits and turbidites,
followed by eruption of large volumes of clast-rich matrix-supported debris flows. Eruption was accompanied by progressive
subsidence to form moat-like features. Later, clast-poor mud flows spread laterally and built up a flat-topped cone (Napoli mud
volcano). Clasts in the mud volcano sediments are mainly angular and up to 0.5 m in size. These clasts are dominated by clay-
stone, sandstone, and limestone of early–middle Miocene age that were previously accreted. Matrix material of the mud brec-
cias probably originated from Messinian evaporite-rich sediments located within the décollement zone beneath the accretionary
wedge, at an estimated depth of 5−7 km. Pressure release triggered hydrofracturing of poorly consolidated mud near the sea-
floor. Eruption was accompanied by release of large volumes of hydrocarbon gas. Conditions were suitable for gas hydrate gen-
esis at shallow depths beneath the seafloor at the Milano mud volcano. The mud volcanism is probably related to backthrusting
concentrated along the rear of the accretionary wedge near a backstop of continental crust to the north. Clasts within the mud
breccias were mainly derived from the North African passive margin, but subordinate lithoclastic ophiolite-related material was
also derived from the north, probably from now largely obliterated higher thrust sheets of Crete. Comparisons show that in con-
trast to other mud volcanoes both on the seafloor (Barbados) and on land (Trinidad), which are usually relatively transient fea-
tures, mud volcanism on the Mediterranean Ridge has persisted for >1 m.y. A revised hypothesis of mud volcanism at the
Ocean Drilling Program sites is proposed, in relation to progressive tectonic evolution of the Mediterranean Ridge accretionary
complex.


millegrazie