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41.
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Rochdale Museum Service holds a large collection of fossils from the important Carboniferous site of Sparth Bottoms (Lancashire, UK; Middle Coal Measures). Several of these are type specimens donated by Harold Howard in 1939. These objects were stored in the museum basement for several decades, and were thought to have been lost. The types are the holotype of the scorpion Eobuthus holti Pocock, 1911 and the holotype of the crustacean Anthrapalaemon grossarti var. holti Woodward, 1911a. These species were not named after Howard, because the describers thought that Fred Holt was the rightful collector. The holotype of the myriapod Euphoberia woodwardi Baldwin, 1911 (put into synonymy with Palaeosoma robustum Baldwin, 1911) is known to have originally been in the collection, but was not located in a recent survey.  相似文献   
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In the Desert Syncline of the southern Georgina Basin there is an Early and Middle Cambrian sequence unconformably overlying late Proterozoic sediments. Stratigraphic drilling and subsequent palaeontological studies have allowed the documentation of the sequence across the Proterozoic‐Cambrian unconformity. Earliest Cambrian green shales are bioturbated and contain distinctive acritarchs. These are overlain, probably unconformably, by sandstone with Diplocraterion burrows, in turn succeeded by archaeocyathan dolostone. Ordian and Templetonian (Middle Cambrian) shales and carbonates unconformably overlie the Early Cambrian sequence. The stratigraphic sequence is very similar to that in the Amadeus Basin and the Adelaide Geosyncline.  相似文献   
45.

The geology, stable isotopes and fluid inclusions from mineralized and unmineralized Middle Proterozoic sequences of the McArthur Basin, Northern Territory, have been studied at Eastern Creek, Bulman Mines, Beetle Springs, and other localities in the McArthur Basin where disseminated sulphides in unmineralized black shales were available from drill core. At Eastern Creek, galena and minor chalcopyrite (δ34S+3.6 to +11.2%o) occur in an evaporitic sedimentary sequence. Barite (δ34S+18.4 to +24.7%o) also occurs, and saline brines are trapped along healed fractures in the barite. Pressure‐corrected trapping temperatures in the barite (95–138°C), and in vein dolomite (158–168°C) agree with temperature estimates from the degree of maturation of the sedimentary organic matter. The δ18O and δ13CCo2 values of the mineralizing fluid were calculated to be +3.5 to +4.5%o and ‐2.7%o, respectively. Sedimentary dolomite has restricted δ13C and δ18O ranges, within the reported ranges for non‐mineralized Middle Proterozoic dolomite. An ore formation model developed for Eastern Creek, in which a basinal fluid at about 200°C carrying base metals and sulphide was released from underlying sediments during local fault movement, may be applicable to a number of other deposits. The mineralization deposited from these fluids occurs only below the pre‐Roper Group unconformity, implying that it may be older than the basal Roper Group. The δ34S values of iron sulphides in fine grained black dolostones (not associated with mineral deposits) from the McArthur Basin were assessed in the light of the values found for sulphides in modern organic‐rich sedimentary environments. The data so obtained suggest that the considerable concentration of iron sulphide in the mineral deposits formed, at least in part, from heated basinal waters and that disseminated iron sulphides remote from mineralization also formed from a similar source.  相似文献   
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Spark source mass spectrometric analysis of the Chassigny meteorite has given the following data (in ppm): Rb 0.4, Sr 7.2, Y 0.64, Zr 1.5, Nb 0.32, Ba 7.1, La 0.39, Ce 1.12, Pr 0.13, Nd 0.54, Sm 0.11, Eu 0.038, Gd 0.11, Tb 0.02, Dy 0.12, Ho 0.03, Er 0.09, Yb 0.10, Pb 1.0, Th 0.057, U 0.021. These data, in conjunction with major element composition and mineralogical and textural features, indicate that this meteorite is an olivinerich cumulate, possibly genetically related to the nakhlites.  相似文献   
48.
Summary Room-temperature Mössbauer spectra of five iron-bearing tourmalines were measured and analyzed. The Fe2+/Fe3+ ratio and the iron occupancy of the Y and Z positions could be assigned to all samples, with the help of two previously well characterized samples, from Mexico and Madagascar. Ferric or ferrous ions or both partially occupy the Z as well as the Y octahedra. This fact of observation is interpreted as the chemical response, during crystal growth, to the requirement of size matching for the edge-sharing Y and Z oxygen octahedra. It accounts for the inexistence of solid solution between the Mg and (Li, Al) tourmalines.
Die Verteilung von Fe2+ und Fe3+ in eisenhaltigen Turmalinen: Eine Mössbauer-Untersuchung
Zusammenfassung Mössbauer-Spektren von fünf eisenhaltigen Turmalinen wurden gemessen und analysiert. Das Verhältnis Fe2+/Fe3+ und die Eisenverteilung konnten mit Hilfe von zwei gut identifizierten Turmalin-Kristallen von Mexiko und Madagascar für die Y-und Z-Lagen aller Exemplare bestimmt werden. Zweiwertiges sowie dreiwertiges Eisen findet sich sowohl in der Z-als auch in der Y-Lage. Da sich die Y-und Z-Oktaeder in einer gemeinsamen Kante treffen, wird diese Beobachtung als chemische Antwort des Kristalles auf die erforderte Größenanpassung der Y-und Z-Oktaeder während seines Wachstums erklärt. Die Abwesenheit der festen Lösung zwischen Dravit und Elbait kann somit erklärt werden.


With 4 Figures  相似文献   
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This paper provides an insight into the numerical simulation of soil–structure interaction (SSI) phenomena studied in a shaking table facility. The shaking table test is purposely designed to confirm the ability of the numerical substructure technique to simulate the SSI phenomenon. A model foundation–structure system with strong SSI potential is embedded in a dry bed of sand deposited within a purpose designed shaking-table soil container. The experimental system is subjected to a strong ground motion. The numerical simulation of the complete soil–foundation–structure system is conducted in the linear viscoelastic domain using the substructure approach. The matching of the experimental and numerical responses in both frequency and in time domain is satisfying. Many important aspects of SSI that are apparent in the experiment are captured by the numerical simulation. Furthermore, the numerical modelling is shown to be adequate for practical engineering design purposes.  相似文献   
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