 | | Journal (article/letter/editorial) | | thin basaltic intrusive sheets in south-eastern Iceland consist in cross-section of a porphyritic central...basaltic intrusive sheets in the Austurhorn area of southeastern Iceland (Fig. 1) are characterized in cross-section...form part of the Tertiary lava pile of eastern Iceland (Walker, 1964). On the east side of Vikurfjall...and a variety of hybrid rocks. This is the Austurhorn intrusion, first noted by Thoroddsen (1896), and described...rocks have been " baked " by the nearby Austurhorn intrusion (Blake, 1966). The porphyritic sheets are |  | | 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of the Tertiary Alftafjordur...centres (Fig. 1) that have been mapped in eastern Iceland (Walker, 1963; Blake, 1964 unpublished Ph.D. thesis...forms the core of the Alftafjordur and the Austurhorn intrusion (Fig. 1; Plate la).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) | | 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 |  | 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) | | anorthite PT E contents range from 42 to 49 (andesine) (Fig. 4a). In contrast, the plagioclases in the...with anorthite contents of 34–50 in the cores (andesine) and 57–69 in the rims (labradorite) PT (Fig...pluton had not completely solidified prior to the intrusion of the D mafic–intermediate dikes, which makes...range of labradorite, which contrasts with the andesine composition (An34–50) of D the phenocryst cores...In such a model, a mushy felsic magma, rich in andesine and low-Mg# amphibole (Mg# = 46–50), would have |  | Cambeses, A., Montero, P., Molina, J.F., Hyppolito, T., Bea, F. (2019) Constraints of mantle and crustal sources and interaction during orogenesis: A zircon SHRIMP U-Th-Pb and O isotope study of the ‘calc-alkaline’ Brovales pluton, Ossa-Morena Zone, Iberian Variscan Belt. Lithos, 324. 661-683 doi:10.1016/j.lithos.2018.11.037 | Journal (article/letter/editorial) | | profile across the northern SPZ, PLZ, OMZ and southern CIZ (Fig. 1A; Simancas et al., 2003). The IRB...4A). Plagioclases in the granodiorite vary from andesine to oligoclase, (Fig. 5D). The finer-grained...Plagioclase shows a zoned pattern with cores of andesine An30-40 , and overgrowth rims Or89-95 (Fig. 5D)...4G). The strongly-zoned plagioclases vary from andesine cores to, predominantly, AC oligoclase rims...Miocene volcanic rocks form Carpathian-Pannonian Region (East-Central Europe) (e.g., Lukács et al., 2018 |  | | Journal (article/letter/editorial) | | inclusions. Rare large resorbed phenocrysts of andesine or oligoclase are present in 0.089- (Fig. 7E)...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 |  | 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 |  | | 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 |
|
