Drilling Shallow-Water Massive Sulfides at the Palinuro Volcanic Complex, Aeolian Island Arc, Italy

2014 ◽  
Vol 109 (8) ◽  
pp. 2129-2158 ◽  
Author(s):  
S. Petersen ◽  
T. Monecke ◽  
A. Westhues ◽  
M. D. Hannington ◽  
J. B. Gemmell ◽  
...  
Keyword(s):  
Shallow Water ◽  
Island Arc ◽  
Volcanic Complex ◽  
Aeolian Island ◽  
Massive Sulfides

Shallow-water polymetallic sulfide deposits in the Aeolian island arc

Geology ◽  
1997 ◽  
Vol 25 (9) ◽  
pp. 815 ◽  
Author(s):  
M. P. Marani ◽  
F. Gamberi ◽  
C. Savelli
Keyword(s):  
Shallow Water ◽  
Island Arc ◽  
Aeolian Island ◽  
Sulfide Deposits

Evidence for an incipient early Caledonian (Cambrian) orogenic phase in southwestern Norway

1983 ◽  
Vol 120 (6) ◽  
pp. 607-612 ◽  
Author(s):  
H. Furnes ◽  
H. Austrheim ◽  
K. G. Amaliksen ◽  
J. Nordas
Keyword(s):  
Continental Crust ◽  
Early Phase ◽  
Island Arc ◽  
Volcanic Complex ◽  
Northern Norway ◽  
Middle Ordovician ◽  
Minimum Age ◽  
Norwegian Caledonides

Summary. Quartz-keratophyres from an ensimatic island arc on Bømlo, southwest Norwegian Caledonides, resting on the Lykling ophiolite, have yielded a Rb/Sr whole rock age of 535 ± 46 Ma. This Cambrian age, which is a minimum age of formation for the ophiolite, indicates an early phase of subduction, corresponding with the orogenic activity known from northern Norway, i.e. the Finnmarkian. Before Middle Ordovician time, the ophiolite and ensimatic arc had been obducted onto continental crust and deformed, as they are unconformably overlain by a volcanic complex of subaerial rhyolites and andesites which have yielded Rb/Sr whole rock ages of 464 ± 16 and 468 ± 23 Ma respectively.

A Late Mesozoic island arc in the southern Andes, Chile

1979 ◽  
Vol 116 (3) ◽  
pp. 181-190 ◽  
Author(s):  
M. Suárez
Keyword(s):  
Continental Crust ◽  
Rift Zone ◽  
Volcanic Rocks ◽  
Upper Jurassic ◽  
Island Arc ◽  
Volcanic Complex ◽  
Late Mesozoic ◽  
Marginal Basin ◽  
The Pacific ◽  
Pacific Side

SummaryThe Hardy Formation, a sequence of Upper Mesozoic volcanic rocks exposed in Peninsula Hardy (Isla Hoste) in the southernmost archipelago of Chile represents, at least in part, the island-arc assemblage of an island-arc-marginal-basin system related to an eastward dipping subduction zone. This island arc was founded on South American continental crust and is also represented in the island of South Georgia 2000 km to the E. The island-arc assemblage includes pyroclastic rocks, characterized by a high proportion of vitric material, and lava intercalations ranging in composition from rhyolite to basalt. These rocks underwent zeolite and prehnite-pumpellyite facies metamorphism and are gently folded, in contrast with the intense folding exhibited by the rocks exposed to the north of Peninsula Hardy. Silicic volcanics assigned to this assemblage underlie pillow lavas, and are intruded by dolerites and gabbros probably related to a Late Jurassic-Early Cretaceous ophiolite magmatism associated with the generation of a quasioceanic marginal basin. Volcanic turbidites (Yahgan Formation) were deposited into the marginal basin.It is suggested that in pre-marginal basin times the Hardy Formation interfingered towards the Atlantic with the silicic volcanics of the Tobifera Formation. However, recent geochemical work on the Tobifera Formation suggest an origin by continental crust anatexis in a volcano-tectonic rift zone related to upper mantle diapirism, whereas an island arc origin is favoured for at least the andesitic and basaltic components of the Hardy Formation. Therefore, the geology of Peninsula Hardy as presented here, confirms early assumptions of the splitting apart of a Middle–Upper Jurassic volcanic terrain along the Pacific margin of South America during the generation of a marginal basin. The spreading axis of the latter seems to have been located at the boundary of two somewhat overlapping petrotectonic assemblages: and island arc on the Pacific side and a silicic volcano-tectonic rift zone towards the Atlantic. A probably Cenozoic volcanic complex discordantly overlies the Yahgan and Hardy formations.

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