Predictor stabilisation of reduction formulae for observations of heavily-damped simple harmonic motions     

H. S. Williams 《Journal of Geodesy》1969,43(1):94

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Comments on Wafer Transfers and Related Problems in Urban Areas     

Roy E. Williams 《Ground water》1968,6(6):6-10

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The Broken Hill ore body,Australia     

Bruce E. Hobbs  David M. Ransom  Ron H. Vernon  Paul F. Williams 《Mineralium Deposita》1968,3(4):293-316

The paper reviews recent works on the Broken Hill ore body to see what data is available on the origin and history of the ore. A high grade metamorphism is recognizable (the Willyama Metamorphism) and this was followed by a number of retrograde metamorphic events. The characteristics of these events is described and this is followed by an analysis of the hypothesis that there is a stratigraphic control of Broken Hill type mineralization. It is concluded that any control that does exist is of a regional nature and that the evidence is equally as good for a restriction of mineralization to areas of high grade metamorphism. Many of the isotopic and geochronological results for Broken Hill are not diagnostic as far as ore genesis is concerned. They do present an internally consistent set of data that records three major events, the Willyama Metamorphism and introduction of the Broken Hill type mineralization at 1700 m. y., the intrusion of the Mundi Mundi Granite and cross cutting pegmatites at 1560 m. y., and retrograde metamorphism and introduction of the Thackaringa Mineralization at or prior to 500 m.y. The sulphides have been deformed in the retrograde schist zones and the ore therefore predates this event. But there is no evidence at the moment that unambiguously establishes that the sulphides were present prior to the Willyama Metamorphism. If it was present prior to or during the Willyama Metamorphism and there is no period of deformation prior to the first recognizable folds at Broken Hill, then the sulphide mass was initially grossly discordant with bedding.

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Zusammenfassung Die Arbeit bringt Ergebnisse der neuesten Untersuchungen über die Broken-Hill-Lagerstätte anschließend an einen Überblick früherer Arbeiten. Der intensiven Willyama-Metamorphose folgen verschiedene retrograde Vorgänge, über die Einzelheiten mitgeteilt werden. Ferner wird die Hypothese einer stratigraphischen Kontrolle der Vererzung einer Prüfung unterzogen und festgestellt, daß die maßgeblichen Frakturen regionaler Natur sein müssen und daß die Beobachtungen somit eine Annahme der Vererzung der hochmetamorphen Gebiete ebenso stark stützt. Viele Resultate von Isotopenzusammensetzungen und geochronologischen Untersuchungen sind für Broken Hill nicht diagnostisch, wenigstens was die Erzgenese betrifft. Sie belegen 3 Hauptereignisse: die Willyama-Metamorphose und den Beginn der Vererzung um 1700.10⁶a, die Intrusion des Mundi Mundi Granits und querschlägiger Pegmatite um 1560.10⁶a und eine retrograde Metamorphose und den Eintritt der Thackaringa-Vererzung um oder vor 500.10⁶a. Die Sulfide sind in der Zone der retrograden Schiefer deformiert worden, was beweist, daß die Vererzung älter ist als dieses Ereignis. Es gibt aber z. Z. keinen Beweis, daß die Sulfide vor der Willyama Metamorphose vorhanden gewesen sind. Wenn sie vor oder während dieses Ereignisses vorhanden gewesen sind und wenn vor der Zeit der ersten deutlichen Falten in Broken Hill keine Deformation stattgefunden hat, dann war die Sulfidmasse ursprünglich in der Schichtung stark diskordant.

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Some statistical parameters obtained from beach sediments     

A.T. Williams 《Proceedings of the Geologists' Association. Geologists' Association》1973,84(1):9-26

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The Influence of Ground-Water Flow Systems on Pavement Stability in Highway Cuts     

R. E. Williams 《Ground water》1967,5(4):23-26

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Reply to P. I. A. Kinnell's comments on ‘the generation and redistribution of overland flow on a massive oxic soil in a eucalypt woodland within the semi-arid tropics of North Australia’, Mike Bonell and John Williams. Hydrological processes, 1, 31–46 (1986)     

Mike Bonell  John Williams 《水文研究》1989,3(1):97-100

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Glaciotectonic structures and their relation to topography at Dinas Dinlle,Arvon, northwest Wales     

Charles Harris  Peter J. Brabham  Graham D. Williams 《第四纪科学杂志》1995,10(4):397-397

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On the source of the slowly varying component at centimeter and millimeter wavelenghts     

Fred I. Shimabukuro  Gary A. Chapman  Earle B. Mayfield  Sidney Edelson 《Solar physics》1973,30(1):163-173

The general features of the slowly varying component at centimeter and millimeter wavelengths are explained by magneto-ionic thermal emission. A model of an active region is constructed in which the electron temperature and density profile is based on recent EUV measurements, and the current-free magnetic field configuration is derived from a longitudinal magnetogram and scalar potential theory. In the model, the contributions of the reflected component of the inward extraordinary wave is important in determining the characteristic features of the radio flux and polarization. Emission by the mechanism of resonance absorption does not appear to be a significant factor in this model.  相似文献   

Lunar physical librations and laser ranging   总被引：1，自引：0，他引：1  

J. G. Williams  M. A. Slade  D. H. Eckhardt  W. M. Kaula 《Earth, Moon, and Planets》1973,8(4):469-483

The analysis of lunar laser ranging data requires very accurate calculations of the lunar physical librations. Libration terms are given which arise from the additive and planetary terms in the lunar theory. The large size of the recently discovered terms due to third degree gravitational harmonics will allow some of these harmonics to be measured, in addition to and, by laser ranging to the Moon. Combining the laser ranging determinations of = 630.6 ± 0.5 × 10^–6 and = 226.4 ± 3.0 × 10^–6 with lunar orbiter measurements ofC ₂₀ andC ₂₂ givesC/MR ²=0.395 _-0.010 ^+0.006 . Numerical integration promises to be an effective method of calculating librations. Comparison of numerical integrations with analytic series indicates that the calculation of the series due to third and fourth degree harmonics is not yet as accurate as the more extensively developed second degree terms.Communication presented at the Conference on Lunar Dynamics and Observational Coordinate Systems, held January 15–17, 1973, at the Lunar Science Institute, Houston, Tex., U.S.A.  相似文献   

Planetary masses and distances     

B. W. Pendred  I. P. Williams 《Astrophysics and Space Science》1969,5(4):420-424

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