volcanic rocks
Geology, Petrology and Geochemistry of Volcanic Rocks Around Arba Minch, Southern Ethiopia
... 11]. Volcanic rocks of Pliocene and Pleistocene age such as pantelleritic rhyolites, trachytes and ignimbrites are abundant within the rift floor and on the adjoining plateau ...
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Mapping local singularities using magnetic data to investigate the volcanic rocks of the Qikou depression, Dagang oilfield, eastern China
... century, volcanic reservoirs have been found globally in large numbers; prominent exam- ples include the Dineh-bi-Keyah syenite reservoirs in Ari- zona in the United States, the Samgori tuff reservoirs in Georgia, ...
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Petrology and geochemistry of volcanic rocks from the Pocdol Mountains, Bicol Arc (Philippines)
... i Volcanic rocks of Pocdol Mountains were produced over a period of 3 Ma, and the deposits formed seven distinct lithostratigraphic units, namely: 1 Malobago volcanics Early Pliocene; 2 [r] ...
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Mineral Chemistry and Thermobarometry of the Upper Eocene Volcanic Rocks in NE Tafresh, Iran
... Eocene volcanic occurrences are the most important volcanic demonstrations In Iran, because it has led to the creation of a volcanic arc which has a length of 1700 km and a width of 100 km [1] ...
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Mineral Chemistry and Thermobarometry of the Volcanic Rocks in Torud, Iran
... sitic rocks of Torud area to understand the geotectonic and geothermobarometry ...calc-alkaline volcanic rocks are exposed around Torud in the Central Ira- nian ...zone. Volcanic rocks ...
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Petrology and Geochemistry of Early Cambrian Volcanic Rocks Hosting the Kiruna-type Iron Ore in Anomaly 10 of Sechahun, Central Iran
... Cambrian volcanic rocks of the Posht-e Badam tectonic block in Central Iran which is hydrothermally altered to green color rocks, hosts the Kiruna-type Iron Oxide- Apatite (IOA) mineralization in ...
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High Potash Volcanic Rocks and Pyroclastic Deposits of Damavand Volcano, Iran, an Example of Intraplate Volcanism
... the volcanic rocks and pyroclastic deposits in Damavand Volcano are displayed using the multi element spider diagram of Pearce (1982) [14], in which elements are normalized against a N-type MORB standard ...
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Petrogenesis of Volcanic Rocks in Alasht, Mazandaran, Iran
... studied rocks are volcanic and semi-volcanic rocks of basic ...These rocks, which form a distinguishable solid mass on 1:100,000 geological map, belong to Cretaceous ...study, ...
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Pedogenesis on volcanic rocks in protected landscape areas in Central and North Bohemia
... on volcanic rocks in Central and North Bohemia was ...on volcanic rocks is weathering of parent ma- terial and development of the Bw horizon with the formation of mainly smectite from the ...
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Paleomagnetic behavior of volcanic rocks from Isla Socorro, Mexico
... syn-caldera rocks is dom- inated by peralkaline rhyolites and ...silicic rocks are porphyritic, with alka- lic feldspar as the dominant phenocryst ...
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The petrology of some young subvolcanic and volcanic rocks from West Kalimantan, Indonesia
... Figure 2.7 Pyroxene quadrilateral after Lindsley & Anderson, 1983 showing composition of phenocrysts in basalt a, andesite and 25 dacite c 2.8 Compositional variations of clinopyroxene a[r] ...
234
The metamorphism of the Cambrian basic volcanic rocks of Tasmania and its relationship to the geosynclinal environment
... The typical porphyritic structure, the nature of the phenocrysts, the still recognisable fluidal structure, the nearly entire absence of dark constituents, the occasional spherulitic for[r] ...
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Petrology of the Volcanic Rocks from Bioko Island (“Cameroon Hot Line”)
... The trace element contents of Bioko lavas Figure 6 are plotted against Th content incompatible element used as geochemical differentiation index and compared to data from Mt Cameroon [18[r] ...
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Potassium Argon ages of Tertiary volcanic rocks, Tasmania
... Central, Southeastern, Northwestern and Northern 26-35 This wHjes.pn~ad volcanism continued the Late OligoceneMiocene but with some to fractionated alkaline lavas Midlands, Eastern, Sout[r] ...
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Tertiary volcanic rocks of far N W Tasmania
... The beds disconformably overlie the Slaughter Bluff Volcanic Breccia and are overlain by a small outcrop of massive basalt correlated with the Little Trefoil Basalts.. The succession is [r] ...
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The Tertiary volcanic rocks of Lower Sandy Bay, Hobart
... The sequence from top to bottom is as follows: Wave-cut Platform 1Vlain Road Cutting Blinking Billy Point basanite 10' basanite 80' 1 red tuff 31 5' 1 - ti basanite tuff 0 15' basanite 2[r] ...
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The petrology of the Cambrian volcanic rocks of Tasmania
... 3.-A specimen of port10n of the surface of a pahoehoe lava flow showing ropy structure FIG 4.-A specimen of breccia containing fragments of volcanic glass showing alteration to hydrogros[r] ...
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Dentition damage in parrotfishes feeding on hard surfaces at Fernando de Noronha Archipelago, southwest Atlantic Ocean
... parrotfishes. Rocks in Fernando de Noronha Archipelago are mostly rough with sharp protu- berances ...plate. Volcanic rocks are much harder than the sedi- mentary rocks that usually comprise ...
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Whole Rock Geochemistry of Host Rocks and K/Ar Age of Hydrothermal Mineral of the Co O Epithermal Gold Deposit, Mindanao, Philippines
... these rocks belong to sub-alkaline andesite and basal- tic-andesite to basalt and alkali basalt in ...The volcanic rocks plot in the island arc tholeiite and calc-alkaline fields of generally ...
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Tuffaceous mud is a volumetrically important volcaniclastic facies of submarine arc volcanism and record of climate change
... nearby volcanic rocks of the Izu ...the volcanic front, rear- arc seamount chains (RASC), smaller Pliocene backarc knolls (BAK), or active rifts (see Hochstaedter et ...the volcanic front ...
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