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Don L. Anderson - One of the best experts on this subject based on the ideXlab platform.
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Volcanoes of the Solar System and Planetary Volcanism: A Study of Volcanic Activity in the Solar System
Physics Today, 1997Co-Authors: Charles Frankel, Peter Cattermole, Don L. AndersonAbstract:Book review of "Volcanoes of the Solar System" by Charles Frankel and "Planetary Volcanism: A Study of Volcanic Activity in the Solar System" by Peter Cattermole
Ward E. Sanford - One of the best experts on this subject based on the ideXlab platform.
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Rapid response of a hydrologic system to Volcanic Activity: Masaya volcano, Nicaragua
Geology, 2008Co-Authors: S. C.p. Pearson, Charles B. Connor, Ward E. SanfordAbstract:Hydrologic systems change in response to Volcanic Activity, and in turn may be sensitive indicators of Volcanic Activity. Here we investigate the coupled nature of magmatic and hydrologic systems using continuous multichannel time series of soil temperature collected on the flanks of Masaya volcano, Nicaragua, one of the most active volcanoes in Central America. The soil temperatures were measured in a low-temperature fumarole field located 3.5 km down the flanks of the volcano. Analysis of these time series reveals that they respond extremely rapidly, on a time scale of minutes, to changes in Volcanic Activity also manifested at the summit vent. These rapid temperature changes are caused by increased flow of water vapor through flank fumaroles during volcanism. The soil temperature response, ~5 °C, is repetitive and complex, with as many as 13 pulses during a single Volcanic episode. Analysis of the frequency spectrum of these temperature time series shows that these anomalies are characterized by broad frequency content during Volcanic Activity. They are thus easily distinguished from seasonal trends, diurnal variations, or individual rainfall events, which triggered rapid transient increases in temperature during 5% of events. We suggest that the mechanism responsible for the distinctive temperature signals is rapid change in pore pressure in response to magmatism, a response that can be enhanced by meteoric water infiltration. Monitoring of distal fumaroles can therefore provide insight into coupled Volcanic-hydrologic-meteorologic systems, and has potential as an inexpensive monitoring tool.
Charles Frankel - One of the best experts on this subject based on the ideXlab platform.
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Volcanoes of the Solar System and Planetary Volcanism: A Study of Volcanic Activity in the Solar System
Physics Today, 1997Co-Authors: Charles Frankel, Peter Cattermole, Don L. AndersonAbstract:Book review of "Volcanoes of the Solar System" by Charles Frankel and "Planetary Volcanism: A Study of Volcanic Activity in the Solar System" by Peter Cattermole
Natan Silva Pereira - One of the best experts on this subject based on the ideXlab platform.
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mercury as a proxy for Volcanic Activity during extreme environmental turnover the cretaceous paleogene transition
Palaeogeography Palaeoclimatology Palaeoecology, 2013Co-Authors: Alcides N. Sial, L.d. Lacerda, Valderez P. Ferreira, Robert Frei, Rosa A. Marquillas, José Antonio Barbosa, Claudio Gaucher, C.c. Windmöller, Natan Silva PereiraAbstract:Abstract The usually low geological background concentrations of Hg makes this trace element suitable for identifying accumulation pulses in sediments that can be tentatively related to weathering processes and thus to climatic changes. Intense volcanism has witnessed the Cretaceous–Paleogene transition (KTB) and was, perhaps, responsible for dramatic climatic changes and decrease in biodiversity and mass extinction. We have used Hg concentrations as a proxy for Volcanic Activity and atmospheric Hg and CO2 buildup across the KTB at three localities. In the Salta Basin, Argentina, Hg contents display several spikes across the KTB, with a maximum value of 250 ng·g− 1. In three drill cores across the KTB in the Paraiba Basin, northeastern Brazil, Hg contents increase from the late Maastrichtian to early Danian and Hg spikes predate the KTB, perhaps, as a record of Volcanic Activity before (but very close to) this transition. At Stevns Klint, Denmark, Hg contents reached almost 250 ng·g− 1 within a 5 cm thick-clay layer, the Fiskeler Member (‘Fish Clay’) that comprises the KTB. Some co-variation between Hg and Al2O3 contents has been observed in all of the studied sections across the KTB, suggesting that Hg is probably adsorbed onto clays. Thermo-desorption experiments in selected samples from the Yacoraite Formation showed Hg+ 2 as the major species present, which is in agreement with a Volcanic origin. Combined Hg and C-isotope chemostratigraphy may become a powerful tool for the eventual assessment of the role of Volcanic Activity during extreme climatic and biotic events, such as those during the KTB.
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Mercury as a proxy for Volcanic Activity during extreme environmental turnover: The Cretaceous–Paleogene transition
Palaeogeography Palaeoclimatology Palaeoecology, 2013Co-Authors: Alcides N. Sial, L.d. Lacerda, Valderez P. Ferreira, Robert Frei, Rosa A. Marquillas, José Antonio Barbosa, Claudio Gaucher, C.c. Windmöller, Natan Silva PereiraAbstract:Abstract The usually low geological background concentrations of Hg makes this trace element suitable for identifying accumulation pulses in sediments that can be tentatively related to weathering processes and thus to climatic changes. Intense volcanism has witnessed the Cretaceous–Paleogene transition (KTB) and was, perhaps, responsible for dramatic climatic changes and decrease in biodiversity and mass extinction. We have used Hg concentrations as a proxy for Volcanic Activity and atmospheric Hg and CO2 buildup across the KTB at three localities. In the Salta Basin, Argentina, Hg contents display several spikes across the KTB, with a maximum value of 250 ng·g− 1. In three drill cores across the KTB in the Paraiba Basin, northeastern Brazil, Hg contents increase from the late Maastrichtian to early Danian and Hg spikes predate the KTB, perhaps, as a record of Volcanic Activity before (but very close to) this transition. At Stevns Klint, Denmark, Hg contents reached almost 250 ng·g− 1 within a 5 cm thick-clay layer, the Fiskeler Member (‘Fish Clay’) that comprises the KTB. Some co-variation between Hg and Al2O3 contents has been observed in all of the studied sections across the KTB, suggesting that Hg is probably adsorbed onto clays. Thermo-desorption experiments in selected samples from the Yacoraite Formation showed Hg+ 2 as the major species present, which is in agreement with a Volcanic origin. Combined Hg and C-isotope chemostratigraphy may become a powerful tool for the eventual assessment of the role of Volcanic Activity during extreme climatic and biotic events, such as those during the KTB.
E V Sharkov - One of the best experts on this subject based on the ideXlab platform.
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neogene Volcanic Activity of western syria and its relationship with arabian plate kinematics
Journal of Geodynamics, 2006Co-Authors: Michele Lustrino, E V SharkovAbstract:Abstract The Cenozoic (mostly Neogene) Volcanic Activity in Syria is part of the extensive magmatism that took place in the Mashrek Region, Middle East, from upper Eocene to Holocene (∼40–0.0005 Ma). Samples in western Syria are mostly high TiO2 (TiO2 ∼1.8–3.7 wt.%) alkaline mafic rocks (basanites, hawaiites and alkali basalts) plus rare transitional/tholeiitic basalts and basaltic andesites) with within-plate-like trace element signature. On the basis of incompatible trace element content, the Volcanic Activity in Syria has been divided into two stages: the first lasting from ∼25 to ∼5 Ma and the second from ∼5 to recent times. Indeed, the Syrian lavas show incompatible trace element content increasing with decreasing age from ∼25 to ∼5 Ma, followed by an abrupt decrease to low values roughly at the Miocene–Pliocene boundary. This temporal shift in composition is related to major tectonic re-organization occurred during upper Miocene. The proposed petrogenetic model invokes three steps: (a) passive upwelling of the shallow asthenosphere during the development of the Dead Sea transform fault system. Different degrees of partial melting were followed by variable extents of fractional crystallization and limited upper crustal contamination; (b) the Miocene–Pliocene boundary tectonic change enhanced passive decompression of the same sources and a consequent increase in degree of partial melting resulting in low incompatible trace element content of the relatively high-volume liquids; (c) after this phase, the incompatible trace element content in the basaltic magmas increased as consequence of fractional crystallization processes. Major and trace element content similarities with the rest of the circum-Mediterranean igneous rocks are consistent with a common relatively shallow origin for the Cenozoic anorogenic magmatism of the entire circum-Mediterranean area (the so-called Common Magmatic Reservoir). Because much of the igneous Activity in the studied area is concentrated near the Dead Sea fault, the origin of Cenozoic magmatism in Syria (and in the rest of the circum-Mediterranean area) reflects a strong lithospheric control on the loci of partial melting. Mantle plumes from lower mantle and/or north-westward channelling of the Afar mantle plume is not needed to explain Volcanic Activity in Syria and the Mashrek area.
