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Nario Kuno Akihiko Hirota Tomoka Tosaki Rie Miura 《Astrophysics and Space Science》2008,313(1-3):293-296
We present recent results of the observations of giant molecular clouds in nearby galaxies with the Nobeyama 45 m telescope
and Millimeter Array. We give some brief comments about observations of GMCs in nearby galaxies with ALMA. 相似文献
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Origin of andesite and its bearing on the Island arc structure 总被引：1，自引：0，他引：1
H. Kuno 《Bulletin of Volcanology》1968,32(1):141-176
The hypothesis that andesite magmas originate from basalt magmas through fractionation is supported for the following reasons: 1) A close association of andesite and dacite with basalt in many volcanoes and a complete gradation in chemistry and mineralogy throughout this suite. 2) Formation of andesite magmas from basalt magmas by differentiation in situ of some intrusive and extrusive bodies. 3) Agreement between the calculated compositions of solid materials to be subtracted from basalt magmas to yield andesite magmas and the observed mineralogy of phenocrysts in these rocks. 4) Higher alkali contents in andesite and dacite associated with high-alumina basalt than in those associated with tholeiite. 5) A complete gradation from the high iron concentration trend of basalt magma fractionation (Skaergaard) to the low or noniron concentration trend (the calc-alkali series) which can be ascribed to the difference of the stage of magnetite crystallization. 6) Similarity between the orogenic rock suite and plateau basalts in the preferential eruption of magmas of middle fractionation stage, givin rise to the great volume of andesite in the orogenic belts and iron-rich basalt in the plateau lavas. Petrological and seismic refraction studies suggest that a great volume of gabbroic materials are present in the lower crust underneath the volcanic belts as a complementary material for the andesite lavas. The island arc structure would develop by repeated eruption of andesite on the surface and by thickening of the oceanic crust underneath the arc due to the addition of gabbroic materials. The suitable portion of the lower crust may be subjected to partial melting to produce granitic magma in the later stage of development of the arc, successively changing it to a part of the adjacent continent. 相似文献
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V.A. Chudaeva S.G. Urchenko O.V. Chudaev K. Sugimory M. Matsuo A. Kuno 《Journal of Geochemical Exploration》2006,88(1-3):101
On the south-eastern edge of Russia, the chemical composition of rainwater is controlled by sea salts, terrestrial material, as well as volcanic (Kuril islands volcanic area) and anthropogenic emissions, mostly in the southern part of the area. The predominant major ions of the Primorye, Sakhalin and the Kuril Islands rainwaters were respectively HCO3−–SO42−, Ca–Na, and of Cl–Na. Concentration of trace elements changes within 1–2 orders of magnitude but some difference in the distribution of the elements between continental and island rainwater is found. The concentration of the chemical elements in the particulate fraction varies from < 10% to 90% of the total concentration (dissolved + particulate) with the following distribution: Tl, Na, Ca, Sr, Zn, Cd (< 10%)–Be, Th, Bi, Rb, U, K, Sc (10–20%)–Cu, Mn, Mg, Mo, Se, Ba, Ni, As, Ag, Cs, Co, Y, Ga, V (20–50%)–Sb, Pb, Ge, Cr, Fe, Al (50–90%).The concentration of elements of the particulate fraction of the rainwater usually is significantly different from concentrations in the crust, including both higher and lower concentrations. The terrestrial contribution to dissolved elements was evaluated and follows the decreasing order: Fe > K, Mg, Ca > Ba, Sr > Na (65–1%). Close order was found for total (dissolved and solid) concentrations. Sea salt contribution to dissolved element concentration in the rainwater decrease in the following order: Cl, Mg > K, SO4 > Ca > HCO3−, Ba, Fe (78–0.1%). Calculation of anthropogenic and volcanic inputs for two ions (Cl− and SO42−) shows that anthropogenic inputs for the Vladivostok and Yuzno-Sakhalinsk cities can be evaluated as 15–20% of Cl− and up to 80–90% of SO42−. Volcanic components in the Kuril Islands, where anthropogenic inputs are absent, can reach up to 76% of SO42− and 36% of Cl−. 相似文献
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O. Chudaev V. Chudaeva K. Sugimori A. Kuno M. Matsuo 《Journal of Geochemical Exploration》2006,88(1-3):95
Among the thermal waters of Mendeleev Volcano three main types can be distinguished: sodium-chloride, acid-sulfate and chloride–sulfate–bicarbonate waters. Contents and behaviors of siderophile, chalcophile, lithophile, and rare-earth elements are discussed. These data, together with the result of isotopic studies (oxygen and hydrogen), are used to discuss the origin of these waters. From the three types of thermal waters, only acid-sulfate waters have a significant input on the chemical composition of the surrounding surface waters. 相似文献
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Trofimova E. A. Zinchenko I. I. Zemlyanukha P. M. Thomasson M. 《Astronomy Reports》2020,64(3):244-258
Astronomy Reports - A survey of massive star forming regions in the lines of the lowest transitions of deuterated molecules DCN, DNC, DCO+, N2D+ in the 4 mm wavelength range was performed using the... 相似文献
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A. R. Breen S. J. Tappin C. A. Jordan P. Thomasson P. J. Moran R. A. Fallows A. Canals P. J. S. Williams 《Annales Geophysicae》2000,18(9):995-1002
Simultaneous observations of the slow solar wind off the southeast limb of the Sun were made in May 1999 using optical measurements from the C2 and C3 LASCO coronagraphs on board the SOHO spacecraft and radio-scattering measurements from the MERLIN and EISCAT facilities. The observations show the slow solar wind accelerating outwards from 4.5 solar radii (R), reaching a final velocity of 200–300 km s-1 by 25–30 R. The acceleration profile indicated by these results is more gentle than the average profile seen in earlier LASCO observations of larger scale features, but is within the variation seen in these studies. 相似文献
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Gene G. Byrd M. Thomasson K. J. Donner B. Sundelius T. Y. Huang M. J. Valtonen 《Celestial Mechanics and Dynamical Astronomy》1988,45(1-3):31-36
We study, theoretically and with N-body simulations, the formation of spiral patterns in retrograde galaxy encounters. A one-armed leading spiral dominates in a disk if the tidal perturbation from the companion is large and the disk is surrounded by a massive halo. Otherwise, a trailing pattern forms. The leading arm is made up of particles in slightly elongated orbits whose turning points outline the arm. The arm rotates opposite to the disk rotation. We have found one spiral galaxy, NGC4622, with a leading arm near its nucleus. From the literature, we find that very few spirals, if any, in a sample of strongly perturbed galaxies have leading arms. A possible reason for this is that few spiral galaxies have a halo with larger mass than the disk within the visible disk. 相似文献