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131.
132.
Summary The total ozone response to strong major geomagnetic storms (Ap≥60) in winter along the 50° N latitudinal circle is studied. The results add to the recent results of Laštovička et al. (1992)
obtained for European middle latitudes (∼50°N) and to the results of Mlch (1994). A significant response of total ozone is
only observed in winter under high solar activity/E-phase of QBO conditions (E-max) and seems to be caused by geomagnetic
storm-induced changes of atmospheric dynamics. There are two sectors along latitude 50°N, which are sensitive to forcing by
geomagnetic storms both in total ozone and the troposphere — north-eastern Atlantic-European and eastern Siberia-Aleutian
sectors. The total ozone response under E-max conditions manifests itself mainly as a large decrease in the longitudinal variation
of ozone after the storm, which means an increase of ozone in Europe. The observed effects in total ozone consist in redistribution,
not production or loss of ozone. 相似文献
133.
Summary The effect of the IMF sector boundary crossing (IMF SBC) in the vorticity area index (VAI) — the well-known dip in the VAI after IMF SBC — is found to be independent of the IMF SBC effect in the cosmic ray flux. This finding refutes a recent suggestion by Lundstedt [1] that the IMF SBC effect in VAI is caused by a decrease in cosmic ray flux, but supports the concept of the IMF SBC effects in the ionosphere and atmosphere developed by Latovika [2–4]. Cosmic rays seem to affect the troposphere in another way.
¶rt;mu nu mau nam aum n ( ) a u¶rt; na¶rt;u aumu () — um uu n — a¶rt; auu m ma nm uu . mm mam nam ¶rt;a n¶rt;u ¶rt;m¶rt;a [1], m m a nuu nma uu , n¶rt;¶rt;uam nu m u u am, aum amu [2–4]. am m uu u m um a mn ¶rt;u a.相似文献
134.
Marcela Laštovičková Y. V. Ramana B. S. Gogte Reviewer A. Janáčková 《Studia Geophysica et Geodaetica》1987,31(1):60-72
Summary Results on electrical conductivity, chemical analysis and age of the rock samples from the Indian Subcontinent are presented. The old Precambrian Indian rocks tend to be less conductive than characteristic rocks of crustal and upper mantle structures.
nuam mam uu mnm¶rt;mu, uu aaua u n¶rt;u u uu n¶rt; u ¶rt;uu. ma nauu n¶rt; u ¶rt;uu naam mn¶rt;m aamumuu n¶rt; u amuu.相似文献
135.
Sulphur-containing compounds in sulphur-rich crude oils from hypersaline lake sediments and their geochemical implications 总被引:1,自引:0,他引:1
Guoying Sheng Jiamo Fu S. C. Brassell A. P. Gowar G. Eglinton Jaap S. Sinninghe Damste Jan W. de Leeuw P. A. Schenck 《中国地球化学学报》1987,6(2):115-126
Three sulphur-rich commercial crude oils have been studied, which contain sulphur as high as up to 4–12%. These samples were
collected from Tertiary hypersaline lake sediments of the Jianghan Basin, Hubei Province at different depths, but above the
oil generation threshold (2200m). FPD-GC and GC-MS data show that aromatic fractions of the crude oils are composed of different
homologues of sulphur-containing compounds, including long-chain normal alkyl-thiophenes and-thiolanes, long-chain isoprenoid-thiophenes
and -thiolanes, and benzothiophenes. It is worth noting that the distribution patterns of long-chain alkyl-thiophenes and
-thiolanes from two shallow-seated crude oils are quite similar to those of normal alkanes showing marked even-odd predominance.
It seems that the even-odd predominance of sulphur-containing compounds decreases with increasing burial depth of the crude
oils. The major component of aliphatic fraction is phytane, and similarly the major peaks of aromatic fractions also represent
C20 isoprenoid thiophenes.
Some preliminary conclusions have been drawn from the above discussion: (1) Abundant sulphur-containing compounds may be used
as an indicator of low mature or immature crude oils produced from hypersaline lake sediments; (2) Sulphur-containing compounds
are considered to be early diagenetic products of reactions between elemental sulphur or sulfides and alkanes or their precursors
(phytols, fatty acids, alcohols, etc.), or of bacterial activities, but not direct inputs of organisms. 相似文献
136.
au uu nu a¶rt;u a amma a nu¶rt; 1966–1981 naa, m ¶rt;, auu m m, u nu u ¶rt; uu n n¶rt;, ¶rt;num nu aa ¶rt; ¶rt;a n n¶rt;. m uu aa ¶rt;u u mu u. 相似文献
137.
aam mam uu mn¶rt;muaamuu n¶rt; u u nua ua —aam auumu m mnam (200–1000°, 2 10–1 a). aa¶rt;u, m um na¶rt;a uu a n¶rt;u auumu mn¶rt;mu m mnam, u¶rt;m auumu ¶rt;a mn¶rt;mu mnam u n¶rt;m mu mnam uma. 相似文献
138.
au a u naam u a nu¶rt; 1963–1973
. naam, m aum mun ma m mm nam aum n (II) na¶rt;am m u a uu ¶rt; u u,¶rt; ua ma u¶rt;, u u¶rt;a ma mn muna. mu u m ¶rt;u mam nm nmum n¶rt;auma amu m m mm II u a¶rt; ¶rt; n. 相似文献
139.
Results of a semi-implicit two-step method for the simulation of markedly nonlinear flow in coastal seas 总被引:1,自引:0,他引:1
Results of a numerical method for the simulation of nonlinear flow in coastal seas are presented. The method is based on a neutral semi-implicit scheme which is modified into a stability-enhancing two-step algorithm. By means of this method the simulation of highly nonlinear flow patterns is possible in a stable and economic way. Three examples of models of different North Sea coastal regions are discussed under certain aspects to demonstrate the reliability of the method. 相似文献
140.
Beatriz Levi Luis Aguirre Jan Olov Nyström 《Contributions to Mineralogy and Petrology》1982,80(1):49-58
Partial spilitization of a 9 km thick pile of flood basalts with highly vesicular flow tops gave rise to patterns of secondary mineralogy at different scales: (a) a local pattern of mineralogical variation from the almost unaltered bottom towards the altered top of each flow, and (b) an overall pattern, comparing flow tops throughout the pile, with changes in mineralogical composition within a sequence of metamorphic zones and facies. The local patterns mimic the trend of the overall pattern, but are of opposite direction and telescoped. Thus, a gradual ordering and Andepletion of the secondary albite and increases in the Fe*/Al ratio of epidote and pumpellyite upwards within individual flows are comparable in range to corresponding overall changes downwards throughout several kilometres. The mineralogical changes within the flows diminish in range towards the more altered deeper part of the pile.The local and overall patterns cannot be interpreted in terms of grade. They represent trends from metastable towards stable equilibrium, this latter only approached in the flow tops of the lower part of the pile. The patterns of secondary mineralogy were formed by an interplay of metamorphic gradients at different scales at any given time, and as burial proceeded. The overall pattern was caused by depth-controlled gradients: increasing P
fluid, temperature and temperature-induced increase of reaction rates, and decreasing fO2 (downwards in the pile). The local patterns resulted from permeability-controlled gradients: increasing reaction rates, fO2 and contrast in chemical activity between different domains, and decreasing P
fluid (upwards in each flow). The mineralogical observations reported in this paper fall into line if the overall temperature-induced increase of reaction rates and the local permeability-controlled rate factors played the leading role during burial metamorphism of the pile. 相似文献