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971.
The distribution of old workings, or ‘minepits’, for clay ironstone in an area between Horsham and Crawley is shown on geological sketch-maps. The geological structure of the area is described in outline. The old workings, except for those in two anomalous patches, are restricted to two argillaceous units in the Upper Tunbridge Wells Sand and to an ironstone horizon some 2 m. below the Horsham Stone in the Weald Clay. Slags from two bloomery sites are described. The amount of ore dug from the minepits is estimated to correspond roughly to the requirements of local blast furnaces, of sixteenth- and seventeenth-century date. Depletion of iron ore reserves is suggested as a factor deciding against resumption of the iron industry in the area after the Civil War. 相似文献
972.
B. Ikwa 《Pure and Applied Geophysics》1971,91(1):218-226
Summary Continuous records of sunshine are available since 1945. These records are carefully checked and interruptions are interpolated by aid of a second station nearby. The homogenized data indicate generally more sunshine from December to May and 15% less from July to November. The fluctuations from one year to the other are rather great, only 1736 hours in 1948 but 2135 hours in 1956. The daily variation is nearly symmetric at M'Bandaka compared to Kinshasa-Binza where are much more clouds in the morning and less in the afternoon. The energetic measurements of global radiation since 1961 show a pronounced minimum in July 346 cal/cm2 d, a secondary maximum in October 416 cal/cm2 d and the principal maximum of 445 cal/cm2 d in March and April. These values are rather low due to clouds as well as to atmospheric turbidity. 相似文献
973.
Summary Expressions are obtained for the currents induced inside a conducting sphere placed in the field of an oscillating magnetic dipole. Interesting conclusions can be drawn from an analysis of the formulas for the current induced due to different orientations of the dipole. 相似文献
974.
975.
The supersaturation of neon in southeastern Pacific deep sea water is unexpectedly high, 6.6% on the average, while surface waters have values about a factor of two lower. A comparison of neon and argon concentrations indicates the presence of injected air in the deep water. The results from surface samples cannot be reconciled with air injection. 相似文献
976.
M. Miyake R. W. Stewart R. W. Burling L. R. Tsvang B. M. Koprov O. A. Kuznetzov 《Boundary-Layer Meteorology》1971,2(2):228-245
In the fall of 1968 an International Intercomparison Experiment was conducted to compare, among other things, acoustic anemometers designed for measurements of atmospheric turbulence. Excellent agreement was obtained in measurements of the vertical component, but an important discrepancy was revealed in measurements of the downwind velocity. The discrepancy proved far more significant in the cospectra than in the spectra themselves. It is evident that great care must be taken in the design of such instruments. An acoustic instrument was shown to have insufficient signal-to-noise ratio to serve as a thermometer under the near-neutral conditions often encountered over water.Comparison of the data-handling and data-analysis techniques showed that although the methods differed widely, the results were essentially identical. 相似文献
977.
978.
Prof. Dr.-Ing. B. Böhnke 《Aquatic Sciences - Research Across Boundaries》1969,31(2):558-564
Ohne Zusammenfassung 相似文献
979.
980.
J. B. Wright 《International Journal of Earth Sciences》1968,58(2):538-564
Sub-alkaline to calc-alkaline granite dominates the high-level plutonic massif of the Serra de Sintra, while two overlapping ring complexes recognised within it consist of four distinct alkaline to sub-alkaline quartz-bearing syenitic units, together with intrusions of a remarkable kaersutite- and (titan?)biotite-bearing theralite heteromorph (Mafraite), contaminated to varying degrees by sialic admixture. Large volumes of sub-volcanic breccia testify to considerable late explosive activity in and near the ring centres. Minor intrusives are approximate compositional counterparts of the plutonic rocks, but more closely resemble lavas forming the extensive “basaltic mantle” of the Lisbon region, where compositions range from olivine basalt, basanite and theralite (luscladite) to subordinate quartz-bearing trachyandesite and trachyte. Undersaturated salic rocks are absent throughout the province. Magmatic differentiation probably played a minimal part in petrogenesis of the Sintra intrusives. The granite is interpreted as a direct product of basement syntexis, the other rocks as products of selective palingenetic reactions between mafraitic magma and crystalline basement (or granite). Evolution of the volcanic and hypabyssal rocks may have been controlled by similar reactions, but evidence favouring differentiation of this suite from sialcontaminated basic parents is almost as strong. There are some points of resemblance between this province and that of the Auvergne region in southern France. 相似文献