 | | Report (chapter) | | and lithostructural characteristics of these ophiolite complexes, suggest that the Rocas Verdes basin...Storey & Mair 1982), and 139 • 2 Ma for the Sarmiento complex, the northernmost in the Rocas Verdes belt...16, 2015 666 C. R. STERN & M. J. DE WIT Sarmiento Complex Recent volcanic rocks Shales (Lower Cretaceous)... 54~ 55 ~ 0 100 ~ ' Beage lCanaJ "Tortuga Complex 200 km Is.Hoste 56 ~ 75 ~ I 70 ~ f Cape Horn...Alabaster 1991). The mafic rocks of the Tortuga complex, the southemmost in the Rocas Verdes belt, are |  | CALDER^|^Oacute;N, M., PRADES, C. F., HERV^|^Eacute;, F., AVENDA^|^Ntilde;O, V., FANNING, C. M., MASSONNE, H.-J., THEYE, T., SIMONETTI, A. (2013) Petrological vestiges of the Late Jurassic-Early Cretaceous transition from rift to back-arc basin in southernmost Chile: New age and geochemical data from the Capit^|^aacute;n Aracena, Carlos III, and Tortuga ophiolitic complexes. GEOCHEMICAL JOURNAL, 47 (2) 201-217 doi:10.2343/geochemj.2.0235 | Journal (article/letter/editorial) | | transition from rift to back-arc basin in southernmost Chile: New age and geochemical data from the Capitán Aracena...Matemáticas, Universidad de Chile, Casilla 13518, Correo 21, Santiago, Chile 2 Escuela de Ciencias de la...Andrés Bello, Salvador Sanfuentes 2375, Santiago, Chile 3 Research School of Earth Sciences, The Australian...spreading/magmatic axis. In the Early Cretaceous Tortuga Complex, tholeiitic basalts are comparable to normal mid-oceanic...et al., 2001) that obtain energy INTRODUCTION Ophiolite complexes, the igneous constituents of idealized |  | | Journal (article/letter/editorial) | | margin of South America [ 1,2,5,9-11] ; (2) the ophiolite sequences, consisting of tholeiitic lavas, dikes...volcanic rocks crop out along both edges of the ophiolite lenses (Fig. 2) [2], although on the Pacific side...paleontologically, apparently thin and pinch out rapidly. In Chile the volcanics belong to the E1 Quemodo Formation...across the eastern margin of the Sarmiento ophiolite complex in Chile near 52°S, in the areas labeled...along the southern shore of Seno Almirantazgo in Chile, about 100 km to the west, and contains Oxfordian-Kimmeridgian |  | | Journal (article/letter/editorial) | | The geology of central Isla Hoste, southern Chile: sedimentation, magmatism and tectonics in part of...Pacific side of a Mesozoic back-arc basin in southern Chile, behind a magmatic arc represented by the Patagonian...oceanic lithosphere which is now seen as partial ophiolite sequences (Dalziel et al. 1974; Stern, De Wit...and to the NE by the shales of the pericratonic Magallanes Basin (Fig. 1; Natland et al. 1974; Dalziel et...cordillera was deposited in the rapidly subsiding Magallanes Basin (Scott, 1966; Winslow, in press). Isla |  | MALONEY, K. T., CLARKE, G. L., KLEPEIS, K. A., FANNING, C. M., WANG, W. (2011) Crustal growth during back-arc closure: Cretaceous exhumation history of Cordillera Darwin, southern Patagonia. Journal of Metamorphic Geology, 29 (6) 649-672 doi:10.1111/j.1525-1314.2011.00934.x | Journal (article/letter/editorial) | | Australia ABSTRACT The Cordillera Darwin metamorphic complex is unique in the Andes in exposing kyanite–staurolite...spessartine–pyrope-rich garnet with biotite, muscovite, plagioclase and quartz inclusions. Micron-scale aqueous inclusions... v v v v v v v v v v 51°S Tortuga Sarmiento Tobifera Fm Darwin Granite Patagonian Batholith...v v v Basement 6000 v v v mafic rocks Ophiolite Upper Jurassic v v v Zapata Fm Volcanoclastic...(sedimentary) K3 126-75 v v v v v v v Magallanes foreland basin Extension v v v v v v Lago |  | | Report (chapter) | | Modelling of oxygen-isotope data from the Sarmiento ophiolite complex, Chile D. Elthon, J. R. Lawrence, R. E....oxygen-isotope investigation of the Sarmiento ophiolite complex show that the extrusive rocks are isotopically...water/rock ratios of 15 to 90. Within the sheeted dyke complex and the plutonic section, the inferred water/rock...1978). It is now generally accepted that most ophiolite complexes represent uplifted sections of oceanic...petrological and geochemical investigations of ophiolite complexes have often been undertaken in an effort |  | | Journal (article/letter/editorial) | | c a t e / s e d g e o Provenance of eastern Magallanes foreland basin sediments: Heavy mineral analysis...the Late Cretaceous to early Miocene eastern Magallanes basin of southernmost Argentina. Our data indicate...derived from the Cordillera Darwin metamorphic complex. Together, these data indicate an abrupt shift...the Scotia Arc. Studying the sediments of the Magallanes basin of the southernmost Andes is ⁎ Corresponding...mineral analyses of sandstones from the eastern Magallanes foreland basin of southern Argentina, which provide |  | | Journal (article/letter/editorial) | | del Fuego and their provenance implications for Magallanes basin sediments Khandaker M. Zahid ⁎, David L...Provenance South America a b s t r a c t The Magallanes foreland basin, located along the northern periphery...Cretaceous to lower Oligocene mudstones of the eastern Magallanes basin, Argentina. The REE patterns of all of...successions and an Eastern Andean metamorphic complex provenance for the younger sediments. The lower...(2013) 69–81 48oS FUEGIAN ANDES TECTONIC ELEMENTS Magallanes Foreland Basin Basement Rocas Verdes Marginal |  | Calderón, M., Hervé, F., Massonne, H.-J., Tassinari, C.G., Pankhurst, R.J., Godoy, E., Theye, T. (2007) Petrogenesis of the Puerto Edén Igneous and Metamorphic Complex, Magallanes, Chile: Late Jurassic syn-deformational anatexis of metapelites and granitoid magma genesis. Lithos, 93 (1) 17-38 doi:10.1016/j.lithos.2006.03.044 | Journal (article/letter/editorial) | | the Puerto Edén Igneous and Metamorphic Complex, Magallanes, Chile: Late Jurassic syn-deformational anatexis...de Geología, Universidad de Chile, Casilla 13518, Correo 21, Santiago, Chile Institut für Mineralogie und...Geología y Minería, Avda. Santa María 0104, Santiago, Chile b c Received 29 May 2005; accepted 22 March 2006...granitoids from the Puerto Edén Igneous and Metamorphic Complex (PEIMC) and biotite–hornblende granitoids of the...the South Patagonian batholith (southern Chile) has been studied. For that purpose, the chemistry of minerals |  | | Journal (article/letter/editorial) | | or ophiolitic breccias that lack a sheeted dyke complex. Stable isotopic data on these unusual ophiolites...phases such as tremolite then chlorite, whereas plagioclase underwent low-T retrograde isotopic exchange...volcanics. If the ‘*O enrichment of the east Ligurian ophiolite is typical of other stratigraphically similar...Introduction Oxygen isotopic studies of large ophiolite complexes such as the Troodos (Cyprus) and Semail...-ka --- Vara Complex (Jur.-Paleocene) Trebbia Supergroup (UCret.) m B Canatelo Complex (Paleogene) CONTINENTAL |  | | Journal (article/letter/editorial) | | Abstract. The Sarmiento and Tortuga complexes are two mafic complexes located in southern Chile that represent...back-arc basin. Basaltic dikes and lavas within each complex exhibit tholeiite differentiation trends whereby...with an increasing negative Eu anomaly. The Sarmiento complex contains intermediate icelandites and silicic...which are conspicuously absent in the Tortuga complex. These non-basaltic compositions have higher Zr...variations. Significantly, in basalts from the Tortuga complex, incompatible elements (Zr, Y, REE) increase in |  | | Book | | continue in the Patagonian Andes of Argentina and Chile over the last years. As a result of this extensive...involved in this complex evolution. Seismicity in the southernmost South America and its complex relation with...de Geología, Universidad Andres Bello, Santiago, Chile Graeme Eagles Helmholtz Centre for Marine and Polar...de Geología, Universidad Andres Bello, Santiago, Chile Gonzalo Galaz Departamento de Geología Regional...Bello, Santiago, Chile; Departamento de Geología, Universidad de Chile, Santiago, Chile Marco Maffione Department |  | | Journal (article/letter/editorial) | | and crystallization of peridotite and gabbro in ophiolite complexes. In the Vourinos, only harzburgite has...phases of deformation in gabbro in much of the complex are interprNed as effects of intense deformation...pile. Gabbroic augen gneiss in the Bay of Islands Complex (Newfoundland, Canada) and widespread tight folding...and ultramafic rocks together in the Zambales Complex (Philippines) are cited as additional evidence...gabbro as metavolcanic rocks in the Tin:,_quillo Complex and at the Lizard (Cornwall, England). INTRODUCTION |  | | Report (chapter) | | Cretaceous volcanic rocks in Colombia, Peru and Chile indicates that: (i) ocean-floor metamorphism (high-T...separates the Northern and Central Andes, and the Chile Rise (Nazca-Antarctica plate boundary) marks the...Ocoite Group in central Chile; and (iv) the Rocas Verdes Group in southernmost Chile (Fig. 1). These units...b Peru ", i "" i I Bohwa 1,... ..... ,:-- Chile..; iI ¢~ s ,'t ; g " i i Ocoife ', Group ...from GR-MS to the Chile Rise (CHR); the Patagonian Andes lies to the south of the Chile Rise. Modified from |  | Feraud, G., Alric, V., Fornari, M., Bertrand, H., Haller, M. (1999) 40Ar/39Ar dating of the Jurassic volcanic province of Patagonia: migrating magmatism related to Gondwana break-up and subduction. Earth and Planetary Science Letters, 172 (1) 83-96 doi:10.1016/s0012-821x(99)00190-9 | Journal (article/letter/editorial) | | this trend with the opening of the Rocas Verdes–Sarmiento marginal basin favors a space–time evolution of...Peninsula, ANT D Antarctica, RVS D Rocas Verdes–Sarmiento basin. The assumed mantle plume head of Karoo...uncertain. A marginal oceanic basin (Rocas Verdes–Sarmiento basin) related to this subduction, and in a back-arc...Fig. 7. The location of the future Rocas Verdes–Sarmiento marginal basin is indicated on both maps. suggested...related to the formation of the Rocas Verdes–Sarmiento marginal basin, at the end of this period. It |  | | Journal (article/letter/editorial) | | received June 15, 1982 In the Bay of Islands ophiolite complex both the basal part of the cumulate gabbro...r n a t i n g b a n d s of s e c o n d a r y plagioclase a n d a m p h i b o l e with few magrnatic m...faults [5,6]. In the Bay o f I s l a n d s ophiolite complex, Newf o u n d l a n d , the b a s a l p a...The Bay of Islands ophiolite: specific characters The Bay of Islands ophiolite complex is located on the...com- LEGEND LOWER ORDOVICIAN AND CAMBRIAN Ophiolite Ophiolite Clolti¢ I Mofite$ Peridotite$ Altochthon |  | | Journal (article/letter/editorial) | | composition from gabbro to granite in the Scourian complex, NW Scotland, are interpreted as due to depletion...Introduction The Archaean gneisses of the Scourian complex represent part of a highly metamorphosed gabbr...be related by fractional crystallisation of plagioclase and hornblende, but there is no direct chemical...metamorphosed to amphibolite facies in the Scourian complex at Gruinard Bay (K/Rb 309 and 470 for tonalites...and, conversely, the Mesozoic Sarmiento ophiolite complex of S. Chile shows K/Rb ratios in excess of |  | | Journal (article/letter/editorial) | | first involving olivine and plagioclase, the second involving plagioclase and clinopyroxene. Fractionation...on continental crust, such as those of the Sarmiento complex. The feisic rocks have strong chemical affinities...and by microprobe traverses, is c o m m o n in plagioclase phenocrysts of mafic and felsic rocks. The amphibole...and associated groundmass plagioclase. The rims and groundmass plagioclase apparently formed during metamorphism...transportation. 41 ~ Z iio: K-FELDSPAR PLAGIOCLASE Fig. 3. Normative K-feldspar-quartz--plagiocla=e |  | | Journal (article/letter/editorial) | | rocks of the district, probably triggered by the Chile ridge±trench interactions that started in Late Miocene...Miocene to Recent collisions of segments of the Chile ridge with the trench (Ramos and Kay 1992). The...GeologõÂ a, Universidad de Chile, Casilla 13518 correo 21, Santiago, Chile 548 Fig. 1 Map showing the...and Wilson 1991) represented by the Sarmiento Ophiolite Complex and volcanoclastic materials. A Jurassic...belt is well exposed between 50° and 43°S near the Chile-Argentina border, and includes sequences that have |  | | Journal (article/letter/editorial) | | OXYGEN AND HYDROGEN ISOTOPE EVIDENCE IN THE XIGAZE OPHIOLITE (TIBET, CHINA)* P I E R R E A G R I N I E R 1...in the Xigaze ophiolite (Tibet, China). Chem. Geol., 71:313-335. The Xigaze ophiolite locally displays...2 5 0 and - 100%o) For the mafic part of the ophiolite, the isotopic compositions correspond to hydrothermal...conditions during which the high-~SO albitized plagioclase formed. This occurrence of amphibolite-facies...meteoric fluids after the obduction. The Xigaze ophiolite sequence displays very little ~SO-depletedrocks |  | | Journal (article/letter/editorial) | | on the mechanisms of back-arc spreading? Many ophiolite complexes are now regarded as the abducted floors...extended loop of the Scotia Arc, represents a complex zone of microplates at the boundary of two major...are fine grained and are composed of olivine, plagioclase, clinopyroxene, chromite and titanomagnetite...resorbed phenocrysts of olivine and plagioclase. Glomerocrysts of plagioclase and olivine are present in basalts...phenocryst assemblages. One (e.g. D24.14) has no plagioclase phenocrysts and only rare olivine phenocrysts |  | | Journal (volume) | | altered containing primary olivine, pyroxenes and plagioclase and having an ophitic texture . Zircons from...:.1/.. . "/\-,-/ ,;;~O U T O K U M P U d:=. COMPLEX ,-...., 1.97 G'; \ 1- \ Fig. 2. Stratigraphy...contact and are entangled with the Outokumpu ophiolite complex (Koistinen, 1981; Vuollo and Piirainen, 1989c)dated...Crossed nicols , photo length 4.5 mm . PL = plagioclase, AMPH = sec. amphibole, OL = olivine , CP X =...4. Iron vs. anorthite content in analyses of plagioclase from diabases in the Koli-Kaltimo area. Iron |  | | Journal (article/letter/editorial) | | Granulite-Facies Metacumulates of the Yakuno Ophiolite, Japan: Evidence for Unusually Thick Oceanic Crust...cumulates, and residual peridotites of the Yakuno ophiolite were thoroughly metamorphosed before its emplacement...Metamorphic grade increases downward through the ophiolite succession, and reaches granulite facies in the...and lower temperatures in the blastomylonites. Plagioclase-olivine reaction and the absence of pyropic garnet...metavolcanics and metacumulates suggests that the Yakuno ophiolite may be a fragment of unusually thick oceanic crust |  | | Report (chapter) | | crustal gabbroic rocks of the Bay of Islands ophiolite complex, Newfoundland, Canada: evidence from mineral...gabbroic crust of the Ordovician Bay of Islands ophiolite complex formed in an island-arc setting near the North...produced pretmite, carbonate and quartz veins, and plagioclase with high 6180. This study documents that the...ophiolitic crust in the Bay of Islands ophiolitic complex occurred mainly along pre-obduction oceanic structures...in an intraoceanic setting. Most oceanic and ophiolite gabbros experienced syn-oceanic hydrothermal alteration |  | | Journal (article/letter/editorial) | | composed predominantly of polycrystalline Na-plagioclase and quartz, with minor hornblende and biotite...(basaltic host) is composed mainly of hornblende, Ca-plagioclase, and quartz. The ocelli are devoid of radial...The ocelli mineralogically are polycrystalline plagioclase feldspar, quartz with subordinate mafic minerals...based base on geochemical data. A sheeted dyke complex, with supra-subduction zone geochemical characteristics... 2007). However, the presence of that sheeted complex has been questioned by Nutman and Friend (2007) |
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