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Showing 1 to 11 of 11 for “"lapilli"”.
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Thermal Modeling of Cooling Time of Submarine Dacite Lapilli Tuff: Brothers Volcano, Kermadec Arc
… of a sphere to create a cooling curve model of a lapilli dacite clast from its initial eruption temperature to the Curie temperature of magnetite to compare to the acquisition of the paleomagnetic remanent vector to test modes of eruption style.</p> <p>The model was created using three initial …
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Age, Growth, and Population Structure of Black Redhorse (Moxostoma Duquesnei) and Golden Redhorse (Moxostoma Erythrurum) in Southwest Missouri
Otoliths (lapilli) were used to age black redhorse (Moxostoma duquesnei) and golden redhorse (Moxostoma erythrurum) from three White River tributaries (James River, Bull Creek, and Swan Creek) and one Arkansas River tributary (Elk River) in southwest Missouri. Validation of annulus formation in …
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Mineralogy and geochemistry associated with hydrothermal alteration of a rhyolitic hyaloclastite from Ponza Island, Italy
… obsidian in a matrix of predominantly pumice lapilli. Incomplete alteration of the hyaloclastite resulted in the non-pervasive argillic zone, characterized by smectite and disordered opal-CT. The other three zones exhibit more complete alteration of the hyaloclastite. The propylitic zone is …
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The Formation of Distal Impact Ejecta
… melt fragments, and accretionary impact lapilli, within this flow.</p> <p>Using our model for spherules produced in the vapor plume, we create a method to estimate the size of an impactor and impact velocity required to create a spherule layer. The impactor size depends on the thickness …
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Historic and prehistoric volcanic activity on St Kitts and Nevis, West Indies: Controls on future hazard
… Mt Liamuiga and Nevis Peak, although subordinate lapilli fallout deposits also occur on St Kitts. The geochemistry of the youngest products at Mt Liamuiga, St Kitts and Nevis Peak have been analysed to characterise the nature of the magma storage conditions below both islands, and to understand …
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Stratigraphic and Geochemical Insights into Explosive Volcanism in Northwestern Nicaragua: Case Studies from the Momotombo-Monte Galán Volcanic System and Cosigüina Volcano
… shifts north to a large compositionally zoned lapilli fall that was deposited 12 km to the west of the summit caldera of Cosigüina volcano. Early erupted dacite pumice and later erupted andesite scoria was sampled at fine scale and a combination of multiple geochemical approaches were applied …
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Studies on late Quaternary tephras in the Waikato and other regions in northern North Island, New Zealand, based on distal deposits in lake sediments and peats
… (14 500); Tongariro: Mangamate (Te Rato Lapilli?) (9950), Okupata (8 informal units Oa-1 to Oa-8: 10 100, 10 500, 10 800, 11 050, 11 200, 11 700, 12 100, 12 700), uncorrelated (13 100). Rotoaira (13 700); Egmont: 15 informal (uncorrelated) units Eg-1 to Eg-15 (2500, 3700, 3750, 4100, …
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Near-vent processes of the 273 ka Poris eruption (Tenerife)
… then occurred, recorded by 9 m of massive lapilli tuff with evidence of widespread scour and bypass, and including lithic-rich layers that record incremental edifice disruption. Laterally variable stratification and load structures show that the PDC was highly non-uniform and unsteady at …
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Hydrogeologische Untersuchungen der Geothermalfelder von Puyehue und Cordón Caulle, Chile
… capas muy permeables de lava en bloque, pómez y lapilli en la superficie son probablemente las áreas de recarga mas importantes. En el altiplano de Cordón Caulle (1300-1500 m s.n.m.) por ejemplo casi toda la precipitación es infiltrada inicialmente. Eso significa un valor extremadamente alto de …