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Abstract

Volcanoes with silica-rich and highly viscous magma tend to produce violent explosive eruptions that result in disasters in local communities and that strongly affect the global environment. We examined the timing of 11 eruptive events that produced silica-rich magma from four volcanoes in Japan (Mt. Fuji, Mt. Usu, Myojinsho, and Satsuma-Iwo-jima) over the past 306 years (from AD 1700 to AD 2005). Nine of the 11 events occurred during inactive phases of solar magnetic activity (solar minimum), which is well indexed by the group sunspot number. This strong association between eruption timing and the solar minimum is statistically significant to a confidence level of 96.7%. This relationship is not observed for eruptions from volcanoes with relatively silica-poor magma, such as Izu-Ohshima. It is well known that the cosmic-ray flux is negatively correlated with solar magnetic activity, as the strong magnetic field in the solar wind repels charged particles such as galactic cosmic rays that originate from outside of the solar system. The strong negative correlation observed between the timing of silica-rich eruptions and solar activity can be explained by variations in cosmic-ray flux arising from solar modulation. Because silica-rich magma has relatively high surface tension (similar to 0.1 Nm(-1)), the homogeneous nucleation rate is so low that such magma exists in a highly supersaturated state without considerable exsolution, even when located relatively close to the surface, within the penetration range of cosmic-ray muons (1-10 GeV). These muons can contribute to nucleation in supersaturated magma, as documented by many authors studying a bubble chamber, via ionization loss. This radiation-induced nucleation can lead to the pre-eruptive exsolution of H2O in the silica-rich magma. We note the possibility that the 1991 Mt. Pinatubo eruption was triggered by the same mechanism: an increase in cosmic-ray flux triggered by Typhoon Yunya, as a decrease in atmospheric pressure results in an increase in cosmic-ray flux. We also speculate that the snowball Earth event was triggered by successive large-scale volcanic eruptions triggered by increased cosmic-ray flux due to nearby supernova explosions. (C) 2010 International Association for Gondwana Research. Published by Elsevier B.V. All rights reserved.

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... The tendency of the confinement of strong earthquakes, either to minima or to maxima of solar activity, is also traced in the analysis of seismicity in specific regions of the planet. For example, [17] studied the relationship between solar activity, volcanic eruptions and seismicity in Japan, it was shown that of the 12 major earthquakes (M≥7.5) that occurred in 1700-2010, nine events (75%) occurred in the solar activity minimums, and the dates of the three earthquakes were timed to the time of solar maxima. Figure 3 shows the strongest earthquakes (magnitude over 7) of the Northern Tien Shan that occurred during the period of the solar grand minimum of Gleisberg (Verny 1887, M7.3; Chilik 1889, M8.3; and Kemin 1911, M8.). ...
... XX ғасырдың ортасында (1950-1965 жж.) жəне XXI ғасырдың басында (2004-2011 жж.) күшті жер сілкіністерін кластеризациялау əсерінің ықтималдығын бағалау [9,10,13] жұмыстарында орындалды жəне оның кездейсоқ ықтималдығы өте аз -0.5%-дан аспайды деген қорытынды жасалды. Жұмыста келтірілген нəтижелер күнлитосфералық байланыстардың болуы идеясын қолдайды [17,19,20,22] жəне қазіргі уақытта планетаның əр түрлі аймақтары үшін жинақталған палеосейсмикалық деректер күшті жер сілкіністері қатарының ұзындығын ұлғайтуы мүмкін, бұл жердің сейсмикалық белсенділігінің ұзақ мерзімді (ғасырлық) вариацияларын анықтауға мүмкіндік береді. ...
... В работах [9,10,13] была выполнена оценка вероятности эффекта кластеризации сильных землетрясений в середине XX века (1950-1965 гг.) и начале XXI века (2004-2011 гг.) и сделан вывод, что вероятность его случайности очень мала -составляет не более 0.5%. Приведенные в работе результаты поддерживают идею существования солнечно-литосферных связей [17,19,20,22] и говорят в пользу того, что палеосейсмические данные, накопленные в настоящее время для различных регионов планеты, могут увеличить длину рядов сильных землетрясений, что позволит выявить более надежно долговременные (вековые) вариации сейсмической активности Земли. ...
... The same result was obtained in papers [52,53]. Also, it was shown in [54] that out of 12 strongest earthquakes (with a magnitude of more than 7.5) that occurred in Japan in 1700-2005, nine events (~70%) were confined to periods of low solar activity, when the intensity of galactic cosmic rays is increased. ...
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... The intensity of the GCR is increased in the solar minimums, resulting in favorite conditions for the GEC's functioning and seismic activity increasing, which is the case. For example, (Ebisuzaki et al., 2011) showed that out of 12 strongest earthquakes (with a magnitude of more than 7.5) that occurred in Japan in 1700-2005, nine events (~70%) were confined to periods of low solar activity, when the intensity of galactic cosmic rays increased. The same relationship holds for seismic activity on the planet as a whole (e.g., Simpson, 1968;Zhang, 1998;Huzaimy and Yumoto, 2011;Khachikyan et al., 2014). ...
Preprint
Full-text available
We have found that about two months after creating a new radiation belt in the inner magnetosphere due to a geomagnetic storm, an increasing seismic activity may occur near the magnetic field lines' footprint. For example, the Combined Release and Radiation Effects Satellite (CRRES) detected a new radiation belt after a geomagnetic storm on March 24, 1991. Shortly after that, on May 30, 1991, a strong M7.0 earthquake occurred in Alaska in the footprint of geomagnetic line L~2.69. Additionally, on October 28, 2012, a strong M7.8 earthquake occurred in Canada near the footprint of L~3.3, which was close to the magnetic lines of a new radiation belt detected by a satellite "Van Allen Probes" after a geomagnetic storm on September 3, 2012. This work considers a geomagnetic conjugation between the Antarctic lithospheric plate boundary in the southern hemisphere and the junction of platforms and orogens in the northern hemisphere. We show that seismotectonic structures in the north and southern hemispheres are located not arbitrarily but controlled by the geometry of the main geomagnetic field.
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... The model was designated PARMA: PHITS-based Analytical Radiation Model in the Atmosphere, and its implementation called EXcel-based Program for calculating Atmospheric Cosmic ray Spectrum (EXPACS) [23] was released to the public. PARMA and EXPACS have been extensively used in various research fields such as radiation protection [24][25][26], semiconductor design [27,28], and geosciences [29][30][31][32][33]. However, the altitude and energy ranges covered by PARMA have, on occasion, proved to be insufficient, particularly when in geosciences research. ...
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... The third hypothesis is most likely with the third agent being cosmic rays of extra-solar origin. That the cosmic rays are correlated with volcanic eruptions of a certain type of volcanoes was pointed out in a recent paper [19], although we may disagree with the explanation provided in the article. We will not try to conjecture any theories here as to how extra-solar cosmic rays may affect the Sun and Earth but merely show the correlation of seismic activity on Earth with CRI. ...
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DOI:https://doi.org/10.1103/PhysRev.91.762
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The major microstructural effects of electron irradiation on silicate glass can be accounted for by a mechanism involving local cation diffusion.
Article
The dependence of the muon flux on the atmospheric parameters (pressure and temperature) is a well-known effect since long time ago. We have correlated the muon flux recorded by the electromagnetic detector of EAS-TOP with the atmospheric temperature (up to few hPa level) monitored by the radio-soundings of the ITAV-Aeronautics Militare at Pratica di Mare (Rome). A significant effect has been observed when the muon flux is correlated with the atmospheric temperature in the region 50-200 hPa, as expected, since this is the region where the mesons of first generation are produced. The technique has been applied to two short periods of strong temperature variations in the low stratosphere, showing that the temporal pattern of the temperature is fairly well reproduced by the variations of the muon flux. The main results of this analysis are presented.
Article
This article reviews the electrical conductivity structures of the oceanic upper mantle, subduction zones, and the mantle transition zone beneath the northwestern Pacific, the Japanese Islands, and continental East Asia, which have particularly large potential of water circulation in the global upper mantle. The oceanic upper mantle consists of an electrically resistive lid and a conductive layer underlying the lid. The depth of the top of the conductive layer is related to lithospheric cooling in the older mantle, whereas it is attributable to the difference in water distribution beneath the vicinity of the seafloor spreading-axis. The location of a lower crustal conductor in a subduction zone changes according to the subduction type. The difference can be explained by the characteristic dehydration from the subducting slab in each subduction zone and by advection from the backarc spreading. The latest one-dimensional electrical conductivity model of the mantle transition zone beneath the Pacific Ocean predicts values of 0.1–1.0 S/m. These values support a considerably dry oceanic mantle transition zone. However, one-dimensional electrical profiles may not be representative of the mantle transition zone there, since there exists a three-dimensional structure caused by the stagnant slab. Three-dimensional electromagnetic modeling should be made in future studies.
Article
Changes in the intensity of galactic cosmic rays alter the Earth's cloudiness. A recent experiment has shown how electrons liberated by cosmic rays assist in making aerosols, the building blocks of cloud condensation nuclei, while anomalous climatic trends in Antarctica confirm the role of clouds in helping to drive climate change. Variations in the cosmic-ray influx due to solar magnetic activity account well for climatic fluctuations on decadal, centennial and millennial timescales. Over longer intervals, the changing galactic environment of the solar system has had dramatic consequences, including Snowball Earth episodes. A new contribution to the faint young Sun paradox is also on offer.
Article
The East Asian continental margin is underlain by stagnant slabs resulting from subduction of the Pacific plate from the east and the Philippine Sea plate from the south. We classify the upper mantle in this region into three major domains: (a) metasomatic–metamorphic factory (MMF), subduction zone magma factory (SZMF), and the ‘big mantle wedge’ (BMW). Whereas the convection pattern is anticlockwise in the MMF domain, it is predominantly clockwise in the SZMF and BMW, along a cross section from the south. Here we define the MMF as a small wedge corner which is driven by the subducting Pacific plate and dominated by H2O-rich fluids derived by dehydration reactions, and enriched in large ion lithophile elements (LILE) which cause the metasomatism. The SZMF is a zone intermediate between MMF and BMW domains and constitutes the main region of continental crust production by partial melting through wedge counter-corner flow. Large hydrous plume generated at about 200 km depth causes extensive reduction in viscosity and the smaller scale hydrous plumes between 60 km and 200 km also bring about an overall reduction in the viscosity of SZMF. More fertile and high temperature peridotites are supplied from the entrance to this domain. The domain extends obliquely to the volcanic front and then swings back to the deep mantle together with the subducting slab. The BMW occupies the major portion of upper mantle in the western Pacific and convects largely with a clockwise sense removing the eastern trench oceanward. Sporadic formation of hydrous plume at the depth of around 410 km and the curtain flow adjacent to the trench cause back arc spreading. We envisage that the heat source in BMW could be the accumulated TTG (tonalite–trondhjemite–granodiorite) crust on the bottom of the mantle transition zone. The ongoing process of transportation of granitic crust into the mantle transition zone is evident from the deep subduction of five intra-oceanic arcs on the subducting Philippine Sea plate from the south, in addition to the sediment trapped subduction by the Pacific plate and Philippine Sea plate. The dynamics of MMF, SZMF and BMW domains are controlled by the angle of subduction; a wide zone of MMF in SW Japan is caused by shallow angle subduction of the Philippine Sea plate and the markedly small MMF domain in the Mariana trench is due to the high angle subduction of Pacific plate. The domains in NE Japan and Kyushu region are intermediate between these two. During the Tertiary, a series of marginal basins were formed because of the nearly 2000 km northward shift of the subduction zone along the southern margin of Tethyan Asia, which may be related to the collision of India with Asia and the indentation. The volume of upper mantle under Asia was reduced extensively on the southern margin with a resultant oceanward trench retreat along the eastern margin of Asia, leading to the formation of a series of marginal basins. The western Pacific domain in general is characterized by double-sided subduction; from the east by the oldest Pacific plate and from the south by the oldest Indo-Australian plate. The old plates are hence hydrated extensively even in their central domains and therefore of low temperature. The cracks have allowed the transport of water into the deeper portions of the slab and these domains supply hydrous fluids even to the bottom of the upper mantle. Thus, a fluid dominated upper mantle in the western Pacific drives a number of microplates and promote the plate boundary processes.
Article
We measured low energy cosmic-ray proton and helium spectra in the kinetic energy range 0.215 – 21.5 GeV/n at different solar activities during a period from 1997 to 2002. The observations were carried out with the BESS spectrometer launched on a balloon at Lynn Lake, Canada. A calculation for the correction of secondary particle backgrounds from the overlying atmosphere was improved by using the measured spectra at small atmospheric depths ranging from 5 through 37 g/cm 2 . The uncertainties including statistical and systematic errors of the obtained spectra at the top of atmosphere are 5–7% for protons and 6–9% for helium nuclei in the energy range 0.5 – 5 GeV/n.
Article
A dense nationwide seismic network recently constructed in Japan has been yielding large volumes of high-quality data that have made it possible to investigate the seismic structure in the Japanese subduction zone with unprecedented resolution. In this article, recent studies on the subduction of the Philippine Sea and Pacific plates beneath the Japanese Islands and the mechanism of earthquake and magma generation associated with plate subduction are reviewed. Seismic tomographic studies have shown that the Philippine Sea plate subducting beneath southwest Japan is continuous throughout the entire region, from Kanto to Kyushu, without disruption or splitting even beneath the Izu Peninsula as suggested in the past. The contact of the Philippine Sea plate with the Pacific plate subducting below has been found to cause anomalously deep interplate and intraslab earthquake activity in Kanto. Detailed waveform inversion studies have revealed that the asperity model is applicable to interplate earthquakes. Analyses of dense seismic and GPS network data have confirmed the existence of episodic slow slip accompanied in many instances by low-frequency tremors/earthquakes on the plate interface, which are inferred to play an important role in stress loading at asperities. High-resolution studies of the spatial variation of intraslab seismicity and the seismic velocity structure of the slab crust strongly support the dehydration embrittlement hypothesis for the generation of intraslab earthquakes. Seismic tomography studies have shown that water released by dehydration of the slab and secondary convection in the mantle wedge, mechanically induced by slab subduction, are responsible for magma generation in the Japanese islands. Water of slab origin is also inferred to be responsible for large anelastic local deformation of the arc crust leading to inland crustal earthquakes that return the arc crust to a state of spatially uniform deformation.
Article
The paper presents a summary of the recent development of the multi-purpose Monte Carlo Particle and Heavy Ion Transport code System, PHITS. In particular, we discuss in detail the development of two new models, JAM and JQMD, for high energy particle interactions, incorporated in PHITS, and show comparisons between model calculations and experiments for the validations of these models. The paper presents three applications of the code including spallation neutron source, heavy ion therapy and space radiation. The results and examples shown indicate PHITS has great ability of carrying out the radiation transport analysis of almost all particles including heavy ions within a wide energy range.
Article
The linkage between multi-decadal climate variability and activity of the sun has been long debated based upon observational evidence from a large number of instrumental and proxy records. It is difficult to evaluate the exact role of each of solar parameters on climate change since instrumentally measured solar related parameters such as Total Solar irradiance (TSI), Ultra Violet (UV), solar wind and Galactic Cosmic Rays (GCRs) fluxes are more or less synchronized and only extend back for several decades. Here we report tree-ring carbon-14 based record of 11-year/22-year solar cycles during the Maunder Minimum (17th century) and the early Medieval Maximum Period (9–10th century) to reconstruct the state of the sun and the flux of incoming GCRs. The result strongly indicates that the influence of solar cycles on climate is persistent beyond the period after instrumental observations were initiated. We find that the actual lengths of solar cycles vary depending on the status of long-term solar activity, and that periodicity of the surface air temperatures are also changing synchronously. Temperature variations over the 22-year cycles seem, in general, to be more significant than those associated with the 11-year cycles and in particular around the grand solar minima such as the Maunder Minimum (1645–1715 AD). The polarity dependence of cooling events found in this study suggests that the GCRs can not be excluded from the possible drivers of decadal to multi-decadal climate change.
Article
During the late Proterozoic from 1000 to 542 Ma, the Earth is thought to have been frozen at least during two times: in the Sturtian (715–680 Ma) and in the Marinoan (680–635 Ma) global glaciations. Following the Marinoan Snowball Earth, large multi-cellular animals of the Ediacara fauna flourished as a prelude to the Phanerozoic world. Here we summarize the most popular models on the cause and cessation of Snowball Earth. Episodic decrease of greenhouse gas occurs through the effect of erosion and weathering promoted by either mountain building or by an increase in the coastlines during the break-up of supercontinents. Effects on the globe caused by true polar wander, eruption of voluminous flood basalts, or dramatic reduction in planetary obliquity can also lead to ice ages and mass extinction. A radically revised concept based on Earth's magnetic intensity has also been proposed, which explains the true polar wander through a quasi-polar dynamo model. The ‘switch-on’ and ‘switch-off’ of the Earth's strong dynamo can lead to the onset and disappearance of the Snowball Earth. The galactic model infers that gamma ray burst associated with starburst creates huge amounts of clouds which would cut off sun rays and freeze the Earth.
Article
Abrupt climate change can trigger volcanic collapses, phenomena that cause the destruction of the entire sector of a volcano, including its summit. During the past 30 ka, major volcanic collapses occurred just after main glacial peaks that ended with rapid deglaciation. Glacial debuttressing, load discharge and fluid circulation coupled with the post-glacial increase of humidity and heavy rains can activate the failure of unstable edifices. Furthermore, significant global warming can be responsible for the collapse of ice-capped unstable volcanoes, an unpredictable hazard that in few minutes can bury inhabited areas.
Article
A network of temperature-sensitive tree-ring-density chronologies provides circum-hemisphere information on year-by-year changes in summer warmth in different regions of the northern boreal forest. Combining these data into a single time-series provides a good summer-temperature proxy for northern high latitudes and the Northern Hemisphere as a whole. Here we use this well dated, high-resolution composite time-series to suggest that large explosive volcanic eruptions produced different extents of Northern Hemisphere cooling during the past 600 years. The large effect of some recent eruptions is apparent, such as in 1816, 1884 and 1912, but the relative effects of other known, and perhaps some previously unknown, pre-nineteenth-century eruptions are also evaluated. The most severe short-term Northern Hemisphere cooling event of the past 600 years occurred in 1601, suggesting that either the effect on climate of the eruption of Huaynaputina, Peru, in 1600 has previously been greatly underestimated, or another, as yet unidentified, eruption occurred at the same time. Other strong cooling events occurred in 1453, seemingly confirming a 1452 date for the eruption of Kuwae, southwest Pacific, and in 1641/42, 1666, 1695 and 1698.
Article
THE eruptive products of calc-alkaline volcanos often show evidence for the mixing of basaltic and acid magmas before eruption (see, for example, refs 1, 2). These observations have led to the suggestion3 that the injection of basaltic magma into the base of a magma chamber (or the catastrophic overturn of a stably stratified chamber containing basaltic magma at its base) might trigger an eruption. Here we report evidence for the mixing of basaltic and dacitic magmas shortly before the paroxysmal eruptions of Pinatubo volcano on 15 June 1991. Andesitic scoriae erupted on 12 June contain minerals and glass with disequilibrium compositions, and are considerably more mafic than the dacitic pumices erupted on 15 June. Differences in crystal abundance and glass composition among the pumices may arise from pre-heating of the dacite magma by the underlying basaltic liquid before mixing. Degassing of this basaltic magma may also have contributed to the climatologically important sulphur dioxide emissions that accompanied the Pinatubo eruptions.
Article
The open solar magnetic flux has been recently reconstructed by Solanki et al. [2000, 2002] for the last 400 years from sunspot data. Using this reconstructed magnetic flux as an input to a spherically symmetric quasi-steady state model of the heliosphere, we calculate the expected intensity of galactic cosmic rays at the Earth's orbit since 1610. This new, physical reconstruction of the long-term cosmic ray intensity is in good agreement with the neutron monitor measurements during the last 50 years. Moreover, it resolves the problems related to previous reconstruction for the last 140 years based on linear correlations. We also calculate the flux of 2 GeV galactic protons and compare it to the cosmogenic 10Be level in polar ice in Greenland and Antarctica. An excellent agreement between the calculated and measured levels is found over the last 400 years.
Article
Galactic cosmic ray scattering and energy loss through solar wind interaction
Article
The eruption of Mount Pinatubo on 15 June 1991 produced the largest stratospheric volcanic aerosol cloud of the 20th century. About 20 megatons of SO2 was injected into the stratosphere, affecting global climate for years. In his Perspective, Robock discusses the climatic lessons learned from the Pinatubo eruption. An accompanying Perspective by Newhall et al. discusses the geologic insights gained from the eruption.
Article
Past studies have suggested a statistical connection between explosive volcanic eruptions and subsequent El Niño climate events. This connection, however, has remained controversial. Here we present support for a response of the El Niño/Southern Oscillation (ENSO) phenomenon to forcing from explosive volcanism by using two different palaeoclimate reconstructions of El Niño activity and two independent, proxy-based chronologies of explosive volcanic activity from ad 1649 to the present. We demonstrate a significant, multi-year, El Niño-like response to explosive tropical volcanic forcing over the past several centuries. The results imply roughly a doubling of the probability of an El Niño event occurring in the winter following a volcanic eruption. Our empirical findings shed light on how the tropical Pacific ocean-atmosphere system may respond to exogenous (both natural and anthropogenic) radiative forcing.
Article
Many major volcanic eruptions coincide with cooling trends of decadal or longer duration that began significantly before the eruptions. Dust veils provide positive feedback for short-term (less than 10 year) global cooling, but seem unlikely to trigger glaciations or even minor climate fluctuations in the 10-to 100-year range. On the contrary, variations in climate lead to stress changes on the earth's crust-for instance, by loading and unloading of ice and water masses and by axial and spin-rate changes that might augment volcanic (and seismic) potential.
Article
Variations in the flux of Galactic Cosmic Rays (GCR) at Earth during the last 4.6 billion years are constructed from information about the Star Formation Rate (SFR) in the Milky Way and the evolution of solar activity. The variations of GCR show a remarkable resemblance to changes in Earth's climate during the period considered, suggesting that Earths climate is closely linked to the evolution of our Milky Way. The link could be significant in the solution of the 'faint sun climate paradox'.
Measurements of 0.2–20 GeV/n cosmicray proton and helium spectra from
  • Y Shikaze
  • S Haino
  • K Abe
  • H Fuke
  • T Hams
  • K C Kim
  • Y Makida
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  • J W Mitchell
  • K Yoshimura
Shikaze, Y., Haino, S., Abe, K., Fuke, H., Hams, T., Kim, K.C., Makida, Y., Matsuda, S., Mitchell, J.W., Yoshimura, K., et al., 2007. Measurements of 0.2–20 GeV/n cosmicray proton and helium spectra from 1997 through 2002 with the BESS spectrometer. Astroparticle Physics 28, 154–167.
Vesicular process in silic magma
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  • V Lyakhovsky
Navon, O., Lyakhovsky, V., 1998. Vesicular process in silic magma. In: Gilbert, J.S., Sparks, R.S.J. (Eds.), Physics of explosive volcanic eruptions: The Geological Society Special Publication, vol. 145.
Quaternary Volcanoes in Japan
  • Geological Survey Of Japan
Geological Survey of Japan, AIST, 2006. Quaternary Volcanoes in Japan. http://riodb02. ibase.aist.go.jp/strata/VOL_JP/EN/index.htm 2006.
  • T Ebisuzaki
T. Ebisuzaki et al. / Gondwana Research 19 (2011) 1054–1061
National Catalogue of the Active Volcanoes in Japan, second edition
  • Japan Meteorological
Japan Meteorological Agency, 1996. National Catalogue of the Active Volcanoes in Japan, second edition. Japan Meteorological Agency, Tokyo.