Continental subduction recorded by Neoproterozoic eclogite and garnet amphibolites from Western Hoggar (Tassendjanet terrane, Tuareg Shield, Algeria)
| dc.contributor.author | Berger, J. | |
| dc.contributor.author | Ouzegane, K. | |
| dc.contributor.author | Bendaoud, A. | |
| dc.contributor.author | Liégeois, J.P. | |
| dc.contributor.author | Kiesnast, J.R. | |
| dc.contributor.author | Bruguier, O. | |
| dc.contributor.author | Caby, R. | |
| dc.date | 2014 | |
| dc.date.accessioned | 2016-03-15T10:06:56Z | |
| dc.date.available | 2016-03-15T10:06:56Z | |
| dc.identifier.uri | https://orfeo.belnet.be/handle/internal/2060 | |
| dc.description | Neoproterozoic eclogite and garnet amphibolites, representing retrogressed eclogites, from the Tassendjanet-Tidéridjaouine terrane in the Pan-African Western Hoggar (Tuareg shield, Southern Algeria) form lenses enclosed in 1.8 Ga subalkaline Paleoproterozoic orthogneisses. They lie along a major sinistral shear zone marking the boundary with the Archean/Paleoproterozoic granulitic In Ouzzal terrane and are associated with high-pressure metasediments. According to thermodynamic calculations, peak condition of the eclogitic stage is 650 °C, 20-22 kbar followed by post-peak heating and exhumation at 730 °C, 10-14 kbar and cooling to 610 °C, 7-10 kbar. Their major, trace-element and isotopic compositions are consistent with emplacement of former basalts in the shoulder of a 700-800 Ma continental rift that evolved to an oceanic basin. The eclogite and garnet amphibolites were thus part of the continental portion of a subducting slab that was pulled down by a denser oceanic lithosphere. Sheath and recumbent folds associated with the exhumation of HP units are verging toward the west, meaning that the former slab was dipping to the east. U-Pb zircon dating on metamorphic zircons bordering ilmenite and rutile in the eclogite gave an age of 623 ± 2 Ma, interpreted as the syn-collisional exhumation stage of the high-pressure unit. This event was rapidly followed by transpressional tectonics and abundant magmatism linked to the northward motion of the adjacent In Ouzzal terrane. | |
| dc.language | eng | |
| dc.publisher | Elsevier | |
| dc.title | Continental subduction recorded by Neoproterozoic eclogite and garnet amphibolites from Western Hoggar (Tassendjanet terrane, Tuareg Shield, Algeria) | |
| dc.type | Article | |
| dc.subject.frascati | Earth and related Environmental sciences | |
| dc.audience | Scientific | |
| dc.subject.free | Geodynamics and mineral resources | |
| dc.source.title | Precambrian Research | |
| dc.source.volume | 247 | |
| dc.source.page | 139-158 | |
| Orfeo.peerreviewed | Yes | |
| dc.identifier.doi | http://dx.doi.org/10.1016/j.precamres.2014.04.002 | |
| dc.identifier.url | http://dx.doi.org/10.1016/j.precamres.2014.04.002 | |
| dc.identifier.rmca | 3648 |
