... and argillite, containing volcanic lithic fragments which are predominantly andesitic in composition. This provenance is most likely the metamorphic preCambrian Basement Complex of southeastern Nigeria in the Oban and Bamenda Massifs/cratons, located at the eastern border of the rift. Basic input from...

... . A double focusing mass spectrometer for geochronology . Int. J. Mass Spectrom. 178 : 43 – 50 . Ekwere , S. J. , and Ekwueme , B. N. 1991 . Geochemistry of Precambrian gneisses in the eastern part of the Oban massif, southeastern Nigeria . Geol. Mijnbouw 70 : 105 – 114 . Ekwueme...

... Pb-evaporation, zircon 581±16 12 Anatectic granite at Toro END Pb-evaporation, zircon 616±12 12 Migmatite at Toro END Rb–Sr, whole rock – biotite 560±10 12 Schist at Obudu Plateau END Pb-evaporation, zircon 665±16 13 Charnockite at Oban massif END Pb-evaporation 585±1 14...

...-sheets, ring-dykes, and cauldron-subsidences Proc. R. Soc. Edinburgh 1936 56 128 57 Bailey E. B. Clough C. T. Tertiary and post-Tertiary geology of Mull, Loch Aline and Oban Mem. geol. Surv. Scotland 1924 445 Billings M. P. Ring-dykes and their origin Trans. N.Y. Acad...

... evaporation ages from the Oban Massif, south eastern Nigeria. Journ. Afr. Earth Sci. 26 , 195 - 205 . Ekwueme , B.N. , Itaya , T. and Yabe , H. , 2000 . K-Ar ages of some metamorphic rocks of Oban massif and their implications for the tectonothermal evolution of southeastern Nigeria...

... in the west by the Benin flank, and in the east by the Calabar flank—a subsurface expression of the Oban massif (Stonely, 1966). It is bounded in the south by the Gulf of Guinea and on the north by older (Cretaceous) tectonic elements, such as the Anambra basin, Abakaliki uplift, and Afikpo syncline ( Ejedawe...

... to a shoreline along the bordering Oban massif. Based on ammonite evidence, early and late Cenomanian are represented ( Reyment, 1954 , 1955 ). The fact that sediments of undoubted Cenomanian age are known only from the Calabar flank led Buser (1965) to suggest a major regression for this time. However...

...: In the Oban Massif there are Cretaceous fractures forming a graben at right angles to the Cameroon trend. 8. Some resu l ts of the Soviet East-Afr lcan Expedit ion By V. V. Beloussov, Academy of Science, U.S.S.R. The Soviet East-African expedition carried out investigations in the region of the East-African...

... in the basin included the crystalline basement areas of the Oban massif, southwestern Nigeria and the Cameroon basement Granites which had undergone prolonged chemical weathering ( Hoque and Ezepue, 1977 ; Amajor, 1987 ; Agumanu, 1993 ; Nwajide and Reijers, 1996 ; Akaegbobi and Schmitt, 1998 ; Akaegbobi...

... of the Oban Massif, Southeastern Nigeria: A preliminary analysis . Chinese Journal of Geochemistry , 28 , 146 – 153 , https://doi.org/10.1007/s11631-009-0146-2 . Ferré , E. , Déléris , J. , Bouchez , J.-L. , Lar , A. , and Peucat , J.-J. ( 1996 ) The Pan-African reactivation...

...John S. Myers; Ronald J. Voordouw; Tanya A. Tettelaar Abstract We present field evidence of the structure and evolution of a typical Proterozoic massif-type anorthosite. The anorthosite forms a batholith composed of numerous plutons and ring complexes intruded episodically in two main sequences...

... sedimentary basin. Paralic and marine/paralic sediments are present only over a restricted area (i.e., where the present Cross River flows between the Abakaliki anticlinorium and the Oban massif) and, in this area, are considered to represent the deposits of the incipient Cross River delta. The delta...

... of the area The Kilmelford intrusive series is located to the south of Oban in Argyllshire, Scotland (Fig. 1). Geological studies in the area began during the 1800s when Survey workers mapped six areas of outcrop and observed the diorite, which was referred to as granite, a large mass of felsite to the south...

...Filip Tomek; Jiří Žák; Martin Svojtka; Fritz Finger; Michael Waitzinger Abstract The late Carboniferous Altenberg-Teplice caldera in the northwestern Bohemian Massif provides an intriguing example of rhyolite eruptions evolving to a trapdoor collapse and coeval ring dike emplacement. Geochemical...

... A. , Gutierrez R. , Nelson E. P. & Layer P. W. 2011 . Geology of the epithermal Ag–Au Huevos Verdes vein system and San Jose district, Deseado massif, Patagonia, Argentina...

... fields, and only formed later as a result of Central Complex-related volcanism. Upton (2004) considered that the environment may have been similar to the present forested landscape surrounding Lake Aydat, a lava-dammed lake in the Chaine des Puys, Massif Central, France. Our interpretation...

... giant dyke swarm, Karoo igneous province, northern Botswana : Journal of Volcanology and Geothermal Research , v. 170 , p. 247 – 261 , doi:10.1016/j.jvolgeores.2007.10.013. Bailey , E.B. , 1924 , Tertiary and post-Tertiary geology of Mull, Loch Aline, and Oban (a description of parts...

..., Ronald Gutierrez, $2,000, Colorado designed to assist students with eld Indonesia, Papua New Guinea, and School of Mines, M.S., Geology of San and laboratory expenses involving the under international waters. Jose Project, NW Deseado Massif Area, study of mineral deposits leading to Patagonia, Argentina...

... grants for thermal alteration and mineralization PhD; Geology and mineralization, CDN$34,500. in mining districts of northern Chile. SW Deseado massif, Santa Cruz, Argentina. These grants will assist students with Alina V. Kuptsova, $3,000, St. Peters- field and laboratory expenses for thesis burg...