 | | Journal (article/letter/editorial) | | thin basaltic intrusive sheets in south-eastern Iceland consist in cross-section of a porphyritic central...the porphyritic zone phenocrysts of plagioclase, augite and olivine are arranged in two main layers, an...and a lower layer containing concentrations of augite and olivine phenocrysts. The phenocrysts are considered...basaltic intrusive sheets in the Austurhorn area of southeastern Iceland (Fig. 1) are characterized in cross-section...porphyritic zone contains phenocrysts of plagioclase, augite and olivine arranged in two main layers, an upper |  | | Journal (article/letter/editorial) | | Maelifell caldera, Alftafjordur volcano, south-eastern Iceland D. H. BLAKE (Plate 27) SUMMARY. The 'Maelifell...given to a separate collapse area situated on the southern margin of the main caldera of the Tertiary Alftafjordur...centres (Fig. 1) that have been mapped in eastern Iceland (Walker, 1963; Blake, 1964 unpublished Ph.D. thesis...forms the core of the Alftafjordur and the Austurhorn intrusion (Fig. 1; Plate la). It is composed basalt...granophyre and intermediate hybrid rocks of the Austurhorn intrusion (Cargill, Hawkes& Ledeboer, 1928; Blake |  | | Journal (article/letter/editorial) | | central volcanic systems of Iceland: constraints from layered gabbro of the Austurhorn intrusive complex Sigurjon...largest gabbro outcrop in Iceland, the Hvalnesfjall gabbro of the 6–7 Ma Austurhorn intrusive complex, have...similar to known transitional olivine basalts from Iceland that had undergone about 20% crystallisation of...present-day magma chambers over the Iceland mantle plume. The Austurhorn central volcano likely formed in...in an off-rift flank zone proximal to the Iceland mantle plume during a major rift relocation. Communicated |  | | Journal (article/letter/editorial) | | of Evolved Basalts and Rhyolites at Austurhorn, Southeastern Iceland: the Role of Fractional Crystallization...April 1992) ABSTRACT The Austurhorn intrusive complex in southeastern Iceland represents the evolved hypabyssal...volcano. The complex consists of a layered gabbro intrusion, a composite granophyric stock, and abundant mafic...the genesis of evolved basalts and rhyolites in Iceland that are difficult to infer from studies of only...Major and trace element variations throughout the Austurhorn suite are consistent with fractional crystallization |  | | Journal (article/letter/editorial) | | AMSTERDAM K-Ar AGES OF THE OLDEST EXPOSED ROCKS IN ICELAND S. MOORBATH Department of Geology and Mineralogy...The University Research Institute, Reyk/avik, Iceland and R. GOODWIN Department of Geology and Mineralogy...oldest exposed lavas in Iceland. The mean values are 12.5 + 0.2 m.y. for eastern Iceland and 16.0 4- 0.3 m...m.y. for northwestern Iceland, or Middle Miocene. The significance of these ages is discussed in relation...production. Several additional age determinations from Iceland are presented which supplement and confirm previously |  | | Journal (article/letter/editorial) | | com/locate/epsl Crustal accretion under northern Iceland J. Maclennan a; *, D. M c Kenzie a , K. Gronvo«ld...Institute, Grensasvegur 50, IS-108 Reykjavik, Iceland c Amerada Hess Limited, 33 Grosvenor Place, London...volcanic systems of the Northern Volcanic Zone of Iceland show two distinct trends. The compositional variation...in the crust and shallow mantle under northern Iceland to be made and these estimates can be used to predict...northern Iceland. ß 2001 Elsevier Science B.V. All rights reserved. Keywords: igneous rocks; Iceland; Kra£a; |  | Batki, Anikó, Pál-Molnár, Elemér, Jankovics, M. Éva, Kerr, Andrew C., Kiss, Balázs, Markl, Gregor, Heincz, Adrián, Harangi, Szabolcs (2018) Insights into the evolution of an alkaline magmatic system: An in situ trace element study of clinopyroxenes from the Ditrău Alkaline Massif, Romania. Lithos, 300. 51-71 doi:10.1016/j.lithos.2017.11.029 | Journal (article/letter/editorial) | | Săndulescu, 1984) of the Alpine– Carpathian–Dinaric region (Fig. 1a) and intrudes the Variscan metamorphic...grained groundmass composed of mostly aegirine-augite needles and small biotite grains of 10–80 µm with...green, subhedral, elongated aegirine and aegirine-augite showing irregular zoning commonly surrounded by...dissolution and are overgrown by a later aegirine-augite rim (Fig. 4e, f). CE 7. Clinopyroxene compositions...respectively), whilst nepheline syenite aegirine-augite (TiO2 < 0.8 wt.%; Al2O3 < 2.5 wt.%) MA and tinguaite |  | | Journal (article/letter/editorial) | | they have been found intergrown with aluminous augite. C o n t a m i n a t e d basalts contain representatives...for basaltic magma have been located outside the region of rhyolitic volcanism (Bacon et al. 1981, Fig...because such continuity of crustal heating by intrusion of basalt seems inconsistent with variable partial...tapped near the upper limit of a zone of basalt intrusion; such melts would only reach the surface outside...Rapid extension of the crust apparently favors intrusion and inhibits eruption of large volumes of basalt |  | Xiong, Fuhao, Ma, Changqian, Chen, Bing, Ducea, Mihai N., Hou, Mingcai, Ni, Shijun (2019) Intermediate-mafic dikes in the East Kunlun Orogen, Northern Tibetan Plateau: A window into paleo-arc magma feeding system. Lithos, 340. 152-165 doi:10.1016/j.lithos.2019.05.012 | Journal (article/letter/editorial) | | investigated pyroxenes phenocrysts are PT E diopside to augite in composition. Although these phenocrysts are...pluton had not completely solidified prior to the intrusion of the D mafic–intermediate dikes, which makes...isotopic D compositions of cordierite granite on southern margin of the Qaidam block, NW China, and PT...on its petrogenesis, tectonic affinity of source region and tectonic implications. Journal of Earth Science...Corfu, F., 2015. The quartz-dioritic Hospitais intrusion (SW Iberian Massif) and its mafic microgranular |  | Shruti, V.C., Jonathan, M.P., Rodríguez-Espinosa, P.F., Nagarajan, R., Escobedo-Urias, D.C., Morales-García, S.S., Martínez-Tavera, E. (2017) Geochemical characteristics of stream sediments from an urban-volcanic zone, Central Mexico: Natural and man-made inputs. Geochemistry, 77 (2) 303-321 doi:10.1016/j.chemer.2017.04.005 | Journal (article/letter/editorial) | | to moderate weathering conditions in the source region. Based on the provenance discrimination diagrams...to felsic volcanic rocks dominated in the study region. Metal contamination indices highlight the enrichment...depositional environment and sources of pollution in the region (Calvert et al., 2001; Glasby et al., 2004; Naimo...2.2. Geological setting Geologically, Tlaxcala region belongs to “Tlaxcala Block” consisting of Tertiary...of the volcanoes (Siebe and Macías, 2004). The region is also fed by a number of small springs, which |  | | Book | | activity at the present day 2 Volcanism 24 3 Intrusion 66 4 Melting and crystallization 121 5 Distribution...the present day At divergent plate boundaries Iceland Submarine eruptions 5 not seen At convergent...Philippines-Sulawesi South-west Pacific New Zealand Sumatra-Java Southern Italy 4 17 42 7 20 15 29 16 15 52 13 24 12 Oceanic...were injected into one another. OCEANIC ISLANDS Iceland is the only active volcanic island to be situated...example Ascension Island and the Galapagos Islands). Iceland is entirely oceanic in character; there is no reason |  | | Book | | Ogata, Andrea Festa, and Gian Andrea Pini (Eds.) Iceland: Tectonics, Volcanics, and Glacial Features Tamie...Revil, Zhenya Zhu, and Evert Slob (Eds.) El Niño Southern Oscillation in a Changing Climate Michael J. McPhaden...seismic profiles beneath southwestern Hualalai and southern Mauna Kea, extrapolated from the seismic tomography...seismic profiles beneath south‐eastern Hualalai and southern Mauna Kea extrapolated from the seismic tomography...et al., 2013). In the case of Hualalai, this intrusion might be as thick as ~3 km. The depth interval |  | | Report (issue) | | The Cu-Ni sulphide ore deposits of the Sudbury region have been known to contain PGE since the discovery...disseminated sulphide ores of the Noril’sk-Taimyr region are described in detail by Komarova et al. They...PGE mineralization in the Monchegorsk layered intrusion (Kola Peninsula, Russia). Exploration activity...the Platinova Reefs in the classic Skaergaard Intrusion. Johan describes several PGE-bearing deposits...of Pd, Pt, Au, Ag and Hg minerals in the Pilbara region of Western Australia. Canadian Mineralogist, 40 |
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