Plutonic rocks can be dense, silica-poor and dark in colour, like most cumulates, or silica-rich and pale in colour like the melt remaining after cumulate formation. |
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In this area, various phases of the Early Devonian South Nepisiguit River Plutonic Suite intrude rocks of both the Miramichi and Tobique zones, obscuring the contact in many places. |
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Plutonic or intrusive rocks result when magma cools and crystallizes slowly within the Earth's crust. |
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These rocks are invariably intensely hornfelsed due to the nearby, and presumably subjacent, intrusions of the South Nepisiguit River Plutonic Suite. |
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Plutonic rocks also tend to be less texturally varied and less prone to gaining structural fabrics. |
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Mr Gutnick was responsible for overseeing the discovery, development and operation of the world class Plutonic, Bronzewing and Jundee gold mines in Australia. |
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The presence of plutonic rocks here suggests that these regions too have been highly extended. |
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Permian and Triassic plutonic complexes comprise monzonite, granite, granodiorite or tonalite with minor gabbro and diorite. |
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Enstatite occurs in plutonic basic and ultrabasic rocks such as peridotite and norite, and also in some high-grade metamorphic rocks. |
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The magmatic fabric of a plutonic rock forms during a relatively short time interval, after ascent and before final crystallization of magma. |
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The present study was conducted entirely in U2 plutonic rocks, which, in the Bonifacio area, are locally covered by Miocene transgressive marine sediments. |
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Overthrusting, volcanism, and plutonic igneous intrusion were identified as originating above the subduction zone where one plate is forced beneath the edge of its neighbour. |
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However, Lower Cretaceous plutonic rocks have not been found in outcrop. |
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Although closely associated with plutonic igneous rocks, porphyry mineralization commonly encompasses large volumes of the surrounding host rocks to the intrusion. |
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Fractional crystallization is usually important in plutonic rocks, whereas liquation can be significant in both plutonic and volcanic environments. |
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It also occurs in acidic plutonic rocks such as granites in association with iron-enriched amphiboles and pyroxenes. |
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A focus is the distribution, nature, age, tectonic setting and metallogeny of volcanic and plutonic rocks. |
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As a result of enormous pressure and high temperature, 20 to 25 kilometres of rocky mass covered the plutonic and metamorphic rock of the area. |
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Mapping of plutonic rocks in the northern and central parts of the map area will also be undertaken. |
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The area between the Pacific Ocean and this valley is formed primarily of plutonic, volcanic and metamorphic rocks. |
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The Frame Lake Trail is underlain by both volcanic and plutonic igneous rocks. |
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A dark greenish-grey plutonic rock that is coarser-grained because it cooled slowly below the surface of the earth. |
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Volcanic and plutonic rocks are similar in composition since they form from the same materials. |
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The misuse of plutonic energies brings, for example, terrorism or the desire to remove enemies or obstacles with wrong means. |
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These metamorphic and plutonic igneous rocks form the uplifted core of the broadly anticlinal Owl Creek Mountains, a mountain range that formed during the Late Cretaceous. |
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In addition to the recognized potential for uranium mineralization in plutonic rocks of Late Silurian to Early Devonian age, there has recently been some interest in exploring for uranium in volcanic rocks of that age. |
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If the magma never reaches the surface, it slowly cools and crystallizes deep below and forms a coarse-grained plutonic rock which is later exposed by erosion. |
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Hypabyssal rocks are less common than plutonic or volcanic rocks and often form dikes, sills, laccoliths, lopoliths, or phacoliths. |
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Mineralogical classification is most often used to classify plutonic rocks. |
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Dikes often form as either radial or concentric swarms around plutonic intrusives, volcanic necks or feeder vents in volcanic cones. |
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Extrusive activity is found in both continental and marine environments, whereas plutonic intrusions are usually linked with areas of uplift such as the Caledonian and Acadian belts of Europe and eastern North America. |
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In older areas of convergence, the composite volcanoes have been eroded, exposing the deeper plutonic granite batholiths that extend the entire length of the convergent boundaries. |
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It is the plutonic equivalent of the volcanic nephelinites. |
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Some plutonic rocks related to the traps escaped crustal contamination reflecting more directly the source of the magmas in the mantle. |
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Shades of rose and pink are used for the Archean plutonic rocks that dominate the Canadian Shield but, in general, are paler than the colours of the Paleozoic granitoid units. |
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Traditionally, these plutons have been considered to form by ascent of relatively buoyant magma in large masses called plutonic diapirs. |
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They show structures intermediate between those of extrusive and plutonic rocks. |
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The protolith for the Scourian gneisses are thought to be granitic, with subsidiary mafic and ultramafic plutonic rocks giving an overall bimodal character. |
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Puerto Rico is composed of Cretaceous to Eocene volcanic and plutonic rocks, overlain by younger Oligocene and more recent carbonates and other sedimentary rocks. |
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Intrusive rocks formed at greater depths are called plutonic or abyssal. |
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