نتایج جستجو برای: volcanic
تعداد نتایج: 14735 فیلتر نتایج به سال:
The Nikuyeh district is located south of the Tarom-Hashtjin metallogenic province in Western Alborz. Oligo-Miocene subvolcanic intrusion and Mid-Eocene volcanic rocks with composition of dacite to andesite are main igneous settings associated with Nikuyeh polymetallic epithermal ore mineralization. Igneous phase in the Nikuyeh district are porphyritic granodiorite, monzodiorite, quartz monsonit...
Visualization of disaster dispersion prediction enables decision makers and civilian to prepare disaster and to reduce the damage by showing the realistic simulation results. With advances of GIS technology and the theory of volcanic disaster prediction algorithm, the predicted disaster dispersions are displayed in spatial information. However, most of volcanic ash dispersion predictions are di...
[1] Explosive eruptions can inject large amounts of volcanic gases into the stratosphere. These gases may be scavenged by hydrometeors within the eruption column, and high uncertainties remain regarding the proportion of volcanic gases, which eventually reach the stratosphere. These are caused by the difficulties of directly sampling explosive volcanic eruption columns and by the lack of labora...
Acidic and basic volcanic and intrusive rocks of Harzandat-Divan Daghy as individual masses, are located in North and Northwest of Marand (Harzandat) and South of Jolfa (Ghareh Gose-Divan Daghy) trending NW-SE.These rocks are located under Permian progressive deposits, which are covered by an igneous sole unconformity. Lithological composition of the acidic volcanic rocks ranges from dacite, rh...
The statistical foundation of disaster risk analysis is past experience. From a scientific perspective, history is just one realization of what might have happened, given the randomness and chaotic dynamics of nature. Stochastic analysis of the past is an exploratory exercise in counterfactual history, considering alternative possible scenarios. In particular, the dynamic perturbations that mig...
Whether the radial thickness (RT) of the chloragogenous tissue and intestinal epithelium of earthworms (Lumbricus terrestris) reflects the bioavailability of metals in soils was investigated in two areas, one with active volcanism (Furnas) and another with no volcanic activity since 3 million years ago (Santa Maria), in the Azores. Metal contents in soil samples and earthworms from the two area...
This paper presents an experimental and theoretical study of the thermal-runaway instability induced by localized microwaves in basalt stones. This effect leads to the inner melting of the basalt core, and further to its eruption similarly to a volcanic burst. The experiments are conducted in a single-mode cavity at 2.45 GHz, 0.9 kW. The microwave-induced miniature volcano exhibits hotspots, bu...
Volcanic activity is often accompanied by many small earthquakes. Earthquake focal mechanisms represent the fault orientation and slip direction, which are influenced by the stress field. Focal mechanisms of volcano-tectonic earthquakes provide information on the state of volcanoes via stresses. Here we demonstrate that quantitative evaluation of temporal stress changes beneath Mt. Ontake, Japa...
The ingestion of volcanic ash by jet engines is widely recognized as a potentially fatal hazard for aircraft operation. The high temperatures (1,200-2,000 °C) typical of jet engines exacerbate the impact of ash by provoking its melting and sticking to turbine parts. Estimation of this potential hazard is complicated by the fact that chemical composition, which affects the temperature at which v...
Magellan data show that the surface of Venus is dominated by volcanic landforms including large flow fields and a wide range of volcanic edifices that occur in different magmatic and tectonic environments. This study presents the results from a comprehensive survey of volcano– rift interaction in the BAT region and its surroundings. We carried out structural mapping of examples where interactio...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید