| Geochemical analyses of these clasts show that the eruption tapped two chemically distinct rhyolitic magmas. |
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| It was characterized by rhyolitic volcanism which appears to have been restricted to the Horn Graben area. |
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| The injection of a mafic magma into a more silicic magma chamber is an important trigger mechanism in moderate-sized andesitic, dacitic and rhyolitic eruptions. |
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| Pumiceous peperite is associated with a rhyolitic sill that intruded wet, unconsolidated, submarine stratified pumice breccia in the Cambrian Mount Read Volcanics, Australia. |
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| As most of the glasses are rhyolitic in composition, the distinction is subtler, being based on small differences in bulk chemistry and volatile contents. |
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| Geochemical variation is common in deposits of many rhyolitic eruptions, especially those from large, caldera-forming events in continental settings. |
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| Dingwell et al. have shown at low dissolved water contents in rhyolitic melts, large changes in melt viscosity can occur for very small changes of water content. |
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| To calibrate major elements, two peralkaline rhyolitic glasses were used. |
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| The oldest rock unit exposed is the arc-related Uriconian Group, consisting of lavas and tuffs of basaltic, basaltic-andesite, dacitic and rhyolitic composition. |
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| Welded tuff is commonly rhyolitic in composition, but examples of all compositions are known. |
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| Both were formed in rhyolitic alluvium and tephra, and had different particle size distributions and different specific surface areas. |
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| The workings appear to loosely follow the upper contact of a grey, altered rhyolitic tuff with an overlying porphyritic rhyolite unit. |
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| This local marker unit conformably overlies an andesitic lapilli tuff and the Little Stand Tuff, a nodular rhyolitic ignimbrite. |
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| Soils at the site are developed on patchy Rotomahana Mud on Kaharoa Tephra overlaying older rhyolitic tephra. |
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| Subordinate units of rhyolitic volcaniclastics with interbedded volcanogenic sandstone and siltstone comprise much of the exposed stratigraphy. |
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| The frequent presence of rounded corroded quartz crystals, such as occur in rhyolitic lavas, helps to demonstrate their real nature. |
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| Primary minerals, in the form of bornite and chalcopyrite, also occur in the underlying volcanic rocks comprising pyroclastics and rhyolitic lavas. |
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| Aluto Volcano is an active, peralkaline rhyolitic complex of Quaternary age, which is characterized by numerous rhyolitic domes forming a 6x9 km large caldera ring structure. |
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| Volcanoes with rhyolitic magma commonly erupt explosively, and rhyolitic lava flows are typically of limited extent and have steep margins, because the magma is so viscous. |
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