Ocean ridge origin and tectonic setting of mesozoic sulphide and oxide deposits of the Argolis Peninsula of the Peloponnesus, Greece

Robertson, AHF; Varnavas, SP; Panagos, AG

dc.contributor.author	Robertson, AHF	en
dc.contributor.author	Varnavas, SP	en
dc.contributor.author	Panagos, AG	en
dc.date.accessioned	2014-03-01T01:39:13Z
dc.date.available	2014-03-01T01:39:13Z
dc.date.issued	1987	en
dc.identifier.issn	00370738	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/22623
dc.relation.uri	http://www.scopus.com/inward/record.url?eid=2-s2.0-0023523473&partnerID=40&md5=c253c60ed6133294442a3980a177915e	en
dc.title	Ocean ridge origin and tectonic setting of mesozoic sulphide and oxide deposits of the Argolis Peninsula of the Peloponnesus, Greece	en
heal.type	journalArticle	en
heal.publicationDate	1987	en
heal.abstract	Metal-oxide and sulphide deposits, chemically similar to the hydrothermal deposits of modern and ancient oceanic spreading axes, occur of the two areas of the Argolis Peninsula of the Peloponnesus, Greece. In the first, in northeastern and central Argolis, manganese ores immediately overlie MORB-type extrusives of mid-Jurassic age. After Triassic rifting this oceanic crust formed during Jurassic time and was then tectonically emplaced over the adjacent continental margin in the Late Jurassic. The manganese ores (Palea Epidavros) were precipitated from low-temperature hydrothermal vent waters on the axis of a relatively unrifted ocean ridge, which was possibly slow-spreading. The deep-sea sediment cover comprises pelagic carbonate accumulated on the ridge flanks, then ribbon radiolarites deposited on the abyssal plain below the CCD, located close enough to a continental margin to allow deposition of shallow water-derived calciturbidites. In the second area, Ermioni, in the southern Argolis Peninsula (Adheres), massive sulphides and metalliferous oxide sediments occur with mafic extrusives and terrigenous turbidites. Although previously regarded as a single stratigraphical succession (""Shale-sandstone Formation""), the mafic lavas and metal deposits are interpreted here as ophiolitic slices that were incorporated into the turbidites by thrusting, possibly as a trench-accretionary complex. The massive sulphides were precipatated from high-temperature vents sited near the axis of a relatively unrifted spreading ridge which was possibly fast-spreading. Ferruginous (ochres) and ferromanganiferous (umbers) oxide sediments were dispersed around these vents, whereas strongly fractionated manganese ores precipitated from separate low-temperature hydrothermal sites. Alternative tectonic scenarios are discussed. © 1987.	en
heal.journalName	Sedimentary Geology	en
dc.identifier.volume	53	en
dc.identifier.issue	1-2	en
dc.identifier.spage	1	en
dc.identifier.epage	32	en