| These are overlain by low-grade metamorphosed sediments and volcanics of Ordovician and Silurian age. |
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| Individual samples weighing 24 kg were collected from the Dal and Bandak volcanics and were crushed and milled. |
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| The radiometric age data combined with the petrography of the volcanics thus indicate two separate events of volcanism in the Danish North Sea. |
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| In this study we concentrate on the field relations and stratigraphy of the pyroclastic deposits within the lower volcanics. |
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| The wide distribution of the volcanics implies that a mantle plume was present beneath northern Australia in the past. |
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| The volcanics were described by Aghabawa as alkaline basalts, hawaiites and mugearites with plagioclase, olivine and augite as the essential constituents. |
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| The Old Red Sandstone and the contemporary volcanics and marine sediments found in Devon originated from these processes. |
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| Correlation between the Hoy volcanics and the other two exposures has been proposed, but differences in chemistry means this remains uncertain. |
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| The most common rocks in West Antarctica are andesite and rhyolite volcanics formed during the Jurassic period. |
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| The basic volcanics are altered andesites, porphyritic diabases and andesites, and various pyroclastics. |
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| The zone is entirely within argillites along the east contact with andesitic volcanics. |
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| These volcanics are a group that includes different volcanic materials such as Incesu ignimbrite and Seksenverentepe volcanite. |
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| The geology of Alaska is typical of that of the cordillera, while the major islands of Hawaii consist of Neogene volcanics erupted over a hot spot. |
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| Acraman occurs in the Gawler Range Volcanics, a Mesoproterozoic continental suite of mainly acid lavas and ash flows. |
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| Volcanic rocks that crop out in the mine area are part of the Portage Lake Volcanics and consist of thin lava flows and interbedded sedimentary rocks. |
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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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| Dale Head stands at the junction of the two main Lakeland geological systems, the Skiddaw slates to the north and the Borrowdale Volcanics to the south. |
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