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551.
552.
Understanding the magnitude and temporal structure of variations in solar ultraviolet and extreme ultraviolet irradiance is critical to understanding solar forcing of the Earth's upper and middle atmosphere and hence to assessing the relative impact of natural and anthropogenic influences on Earth's atmospheric environment. Satellite based measurements of such variations are limited to recent times, are short in duration and subject to gaps making necessary ground-based surrogates with longer and more continuous coverage. Using indices derived from synoptic solar magnetograms taken at the Mount Wilson 150-foot solar tower, we have constructed models of several UV and near EUV lines and fluxes which correlate strongly (r > 0.90) with satellite data. These lines and fluxes include the Mgii h and k core-to-wing ratio, the Lα line and the 200–205 nm flux. 相似文献
553.
554.
对南极长城站附近棕贼鸥(C.s.lonnberg)、灰贼鸥(C.maccormicki)和两者的混合配对(hybrid)的食性与考察站环境质量的相关性进行研究,结果表明,贼鸥的食物结构受站区人类废弃物的直接影响。贼鸥食性构成同时与人类活动和动物生态习性相关而起到双重信息载体作用,可作为南极环境生态评价的重要指标之一,对推动实现南极环境生态评价的量化有重要意义。 相似文献
555.
Ulrich Kramm 《Contributions to Mineralogy and Petrology》1979,69(4):387-395
In highly oxidized Mn- and Al-rich layers of the low-grade metamorphic metasediments north of Salmchâteau, Belgium, three types of viridine porphyroblasts can be distinguished: (a) single-phase porphyroblasts, (b) composite porphyroblasts with a core consisting of very fine-grained kaolinite, which is interpreted as a pseudomorph after andalusite, and a rim of viridine and, (c) composite porphyroblasts with a viridine core, a first mantle of kaolinite (as a pseudomorph after andalusite) and a second rim of viridine. These grains form an assemblage with muscovite, paragonite, Mg-chlorite, piemontite, braunite, hematite, quartz, rutile, and apatite. In the single-phase porphyroblasts the chemical composition of the core, (Mn
0.51
3+
Al0.44Fe
0.04
3+
)Al(O/SiO4), grades continuously into (Mn
0.79
3+
Al0.15Fe
0.06
3+
)Al(O/SiO4) of the rim. The outer zones of the analyzed grains are thus richer in kanonaite-component, MnAl(O/SiO4), than the original kanonaites described recently by Vrána et al. (1978) from the type locality in Zambia. Taking into consideration also other chemical data of viridines of the Salmchâteau locality there exists a complete solid solution series in the system Al2SiO5 (And)-MnAlSiO5 (Kan)-FeAlSiO5 at least from And61Kan37(FeAlSiO5)2 to And15Kan79(FeAl-SiO5)6 for the P-T conditions verified here ( 400 ° C/1–2 kb). The oxygen fugacity of the rocks is estimated to correspond to f
O2 of the MnO2/ Mn2O3-buffer or to exceed it. Single-phase and composite porphyroblasts of the andalusite-type minerals contain S-shaped internal structures, which, in the marginal parts of the grains, are always oriented perpendicular to the schistosity planes. Together with the zoning of the composite grains these structures give clear evidence, that the andalusite formation is preceded by viridine growth in suitable rocks high in manganese. Thus, the viridines of the cores are formed under P-T conditions of less than 360–380 ° C/1–2 kb. The recurrent availability of Mn to form the kanonaite-rich rims in all three types of porphyroblasts may be explained by Mn release out of the recrystallizing hematites along the schistosity planes during decreasing temperatures.Although the Commision on New Minerals and Mineral Names, IMA, has deleted the classical name viridine it is preferred here and used as a varietal name for all intermediate members of the solid solution series between andalusite, Al2(O/SiO4), and the recently described kanonaite, MnAl(O/SiO4) (Vrána et al., 1978). This is done with special regard to the petrographie purpose of this investigation, since it is impracticable and by simple optical methods in strongly zoned crystals even impossible to distinguish between manganian andalusite [Al(6)>Mn] and aluminous kanonaite [Al(6)相似文献
556.
Privatdozent Dr. Ulrich Rosenfeld 《International Journal of Earth Sciences》1968,57(2):402-424
Zusammenfassung Die sandige Fazies des Schilfsandsteins ist in Ost-Lippe rhythmisch aufgebaut. Diese Abfolge ist so konstant, daß sie als stratigraphische Gliederung verwendbar ist. Einzelne Schichtglieder lassen sich bis maximal 2500 m Erstreckung verfolgen und als Leithorizonte benutzen. Das gilt auch beim Übergang in andere Faziesbereiche. Die Sandsteine selbst sind ebenfalls (z. T. undeutlich) rhythmisch entwickelt; die Zuordnung von Rhythmen ist in einigen Fällen möglich. Modalbestands-Analysen, Korngrößen- und Karbonat-Bestimmungen ergeben keine feinere Untergliederungsmöglichkeit der Schichtfolge. Sie vermögen die makroskopische Schichtgliederung teilweise zu stützen bzw. zu ergänzen. - Ausblick auf Sedimentationsverhältnisse im Untersuchungsgebiet und arbeitsmethodische Fragen.
The sandstone-facies of the Schilfsandstein (km2) in the eastern part of Lippe (eastern Westphalia) shows a rhythmic sedimentation, which may be used as a stratigraphic subdivision. Some layers continue on distances up to 2500 m and partly give the possibility to connect the silty and the sandstone-facies. The lithologic subdivision is only in some degree controlled by means of modal analysis, mechanical and carbonate analysis. - Short review of sedimentary and methodic problems.
Résumé Le faciès gréseux du Schilfsandstein (km2) dans la partie de l'est de Lippe (Westphalie orientale) est sédimenté rhythmiquement. Cette manière de sédimentation peut être usée à une subdivision stratigraphique. Quelques bancs peuvent être suiviès jusqu' à une distance de 2500 mètres; cela rend possible en partie une corrélation des faciès de silt et de grès. On peut contrôler la subdivision lithostratigraphique seulement en partie à l'aide d'analyses minérales et granulométriques et par détermination du carbonate. - Aperçu des problèmes sédimentologiques et méthodiques.
. , . 2500 , , . . , . , . .相似文献
557.
Ulrich Kramm 《Contributions to Mineralogy and Petrology》1976,56(2):135-155
Thin spessartine-quartzite layers (coticules) are interstratified with Ordovician (Salmian) shales of the Venn-Stavelot Massif, Ardennes. These coticules indicate sudden interruptions in the sedimentation process of the shales. The lower contact of the coticules represents an abrupt change in the chemical composition from the underlying shales. In contrast, the upper limit of the coticules is chemically more diffuse. Phase relations of the phengitebearing spessartine-quartzites including paragonite, chlorite, and chloritoid or kaolinite as subordinate phases give evidence for a manganese-montmorillonitic source material of the coticules. This is in good agreement with the internal structures observed in the coticule layers (swelling and sliding effects, Liesegang structures). Since there is a positive correlation between the oxidation ratio of the enclosing shales and the chemical composition of the coticules, it is proposed that the source material of the coticules developed in situ by halmyrolysis out of tuffs. High oxidation ratios of the shales with iron fixed in the trivalent state but with divalent and thus mobile manganese led to the formation of coticule starting material, dominantly a manganese-montmorillonite. Halmyrolysis products formed under low oxidation ratio conditions of the enclosing shales are characterized by hydrosilicates rich in iron. The Obrochishte manganese deposit, Bulgaria, is discussed as a nonmetamorphic equivalent of the coticules of the Ardennes. 相似文献
558.
Dr. Ulrich Zimmermann Peter Suter-Weider Dipl. phil. nat. 《Aquatic Sciences - Research Across Boundaries》1976,38(2):71-96
Chemical and physical conditions of the Walensee are discussed on the basis of values analyzed during an investigation period
in the years 1972–1975. Thereby values of selected parameters have been compared with data of other Swiss lakes to estimate
the trophic condition of the lake.
相似文献
559.
Dr. Ulrich Manze Dr. John C. Vogel Dr. Reinhard Streit Prof. Dr. Karl Brunnacker 《International Journal of Earth Sciences》1974,63(3):885-897
The ratio of oxygen and carbon isotopes is a criterion for the carbonate-genesis with distinct differences between marine, freshwater, soil and loess carbonates. In addition it becomes clear that there is a number of carbonate soils within the loess of the mediterranean region with distinguishable isotopic compositions. The components affecting the relation of the isotopes in these loesses and the intercalated soils are discussed. The carbonate-turnover during the sedimentation of the loess with carbonate-precipitation from remnant solutions seems to be of some importance. The relatively small participation of biogenic CO2 in the carbonate-turnover ist evident. 相似文献
560.
Time series measurements from light vessel and coastal stations in the transition area of the Kattegat and the Baltic Sea are analyzed for the period August 1975 to March 1976. The data consist of daily sampled salinities from different depth levels and daily means of sea levels, surface current, and wind, respectively. The purpose of this paper is to examine the dynamics of the mass- and salt-transport during a major salt water inflow.The principal conclusions of this paper are that
相似文献
1) | the dynamics of the barotropic water exchange between the Kattegat and the Baltic Sea resembles that of a Helmholtz-resonator with a geostrophically controlled flow in the connecting channel; |
2) | the water exchange is forced by both the east component of the windstress over the North Sea and the windstress component in 30o true over the Baltic Sea; |
3) | the salinity in the upper layer of the Kattegat is governed by a permanent weak salt flux directed from the bottom to the surface layer and the outflow of less saline Baltic water into the upper layer of the Kattegat whereas the salinity of the Belt Sea is advected by the local currents along the main channel; |
4) | the most favorable conditions for a major salt inflow are initially a mean sea level of the Baltic lowered by about 30 cm followed by west winds steadily increasing over the following several ten days. Moreover, the hitherto used definition of a major salt water inflow is discussed and an improved definition is proposed. |