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41.
Dr. E. K. Walton 《International Journal of Earth Sciences》1960,50(1):63-77
Lower Palaeozoic successions in the Southern Uplands are much thicker than previously supposed and sedimentation may have lasted well into Ludlow times. Volcanic rocks are Arenig and Glenkiln in age and are often interbedded with greywackes and shales. Lapworth's concept of the structure as an anticlinorium and a synclinorium is rejected and it is suggested that the rocks have been folded into a series of compound monoclines which face north-westwards. These are probably cut by strike faults which bring up the older beds to the north.
Zusammenfassung Die altpaläozoischen Schichtfolgen in den Südlichen Hochlanden sind viel mächtiger, als bisher angenommen wurde, und die Ablagerung kann bis ins Ludlow gereicht haben. Vulkanite haben Arenig- und Glenkiln-Alter; sie wechsellagern oft mit Grauwacken und Tonschiefern.Lapworths Vorstellung, der tektonische Bau sei ein Antiklinorium und ein Synklinorium, wird bestritten. Es wird angenommen, daß die Gesteine zu zusammengesetzten Monoklinen gefaltet wurden, deren steile Flügel nordwestwärts weisen. Sie werden wahrscheinlich durch streichende Verwerfungen zerschnitten, die die älteren Schichten im Norden herausheben.相似文献
42.
43.
Bruce G. Aitken 《Geochimica et cosmochimica acta》1983,47(3):351-362
At a total pressure of 5 kb, calcic, Cl-free scapolite (Me83) is stable relative to plagioclase-bearing assemblages at , . With decreasing temperature, scapolite breaks down to plagioclase + calcite. Scapolite is replaced by plagioclase + grossular + cancrinite + CO2 in the presence of H2O-rich fluids. The stable coexistence of scapolite and calcite, an assemblage typical of most natural occurrences of calcic scapolite, is limited by the reaction: scapolite + calcite → grossular + cancrinite + CO2, which occurs at 750°C, XCO2 = 0.46; 700°C, XCO2 = 0.33; 650°C, XCO2 = 0.18, for the chosen bulk composition.Generalization of the experimental results to encompass the complete range of fully carbonated scapolite compositions indicates that mizzonite (Me75) has the largest T-XCO2 stability field. For scapolite more calcic than mizzonite, stable growth is restricted to conditions of increasingly higher temperature and XCO2.The experimental results are consistent with various petrologic features of scapolite-bearing rocks, particularly scapolite-clinopyroxene granulites, and indicate that such rocks were formed in the presence of CO2-rich fluids. 相似文献
44.
Summary The motion of a non-viscous liquid medium with an ideal electrical conductivity, enclosed in the ellipsoidal cavity of an envelope subject to precessional motion, is investigated. Inside the cavity there is a toroidal magnetic field. It is proved that the precessional motion of the envelope generates forced oscillations of the medium with a period of 24 hours and two different types of eigen oscillations. Expressions for computing the amplitudes and frequencies of all types of oscillations are derived. The maximum values of disturbance fields are determined for geophysically acceptable parameters. 相似文献
45.
46.
This paper considers volcanogenic exhalation mineralization using data from 35 years of observation of fumarole activity during an earlier phase of the posteruptive activity of the Second Cone, which is one of the New Tolbachik volcanoes that were formed during the eruption at the North Vent of the Great Tolbachik Fissure Eruption (Kamchatka, 1975–1976). We describe the main types of mineral associations, identify the key mineral species and the secondary and accessory minerals, as well as the sequence of mineral generation. We provide a summary of minerals and compounds that have been identified in ejecta of fumaroles on the Second Cone. 相似文献
47.
Summary Litton Divisions presently produce both high accuracy GPS surveyors and low—cost GPS navigation sets. Aero Service'sMACROMETER
R Interferometric Surveyors, have become the standard against which GPS surveying equipment is measured. Litton Aero Products
has developed a highly digitized, low costL
1,C/A code GPS card set. The integration of these technologies had led to the development of a low-cost, high-precision, GPS survey
system which can be configured with or without a codelessL
2 capability.
TheMINI-MAC surveying system is the first member of the new generation of GPS survey systems resulting from this joint development. The
system design is described in this paper, and initial survey test results using a prototypeMINI-MAC surveying system are presented. 相似文献
48.
G. Dautcourt 《Astronomische Nachrichten》1980,301(4):155-156
The two-point covariance function of galaxy clustering is discussed for small and large values of its argument. 相似文献
49.
Reply to comment on ‘Up‐scaling potential impacts on water flows from agricultural water interventions: opportunities and trade‐offs in the Osman Sagar catchment,Musi sub‐basin,India’. Hydrological Processes 27: 3905–3921 by Bouma et al., 下载免费PDF全文
Kaushal K. Garg Suhas P. Wani Jennie Barron Louise Karlberg Johan Rockstrom 《水文研究》2014,28(8):3352-3355
50.
Dubey Om Prakash Niwas Sri Awasthi A. K. 《Journal of the Indian Society of Remote Sensing》1986,14(1):39-44
Journal of the Indian Society of Remote Sensing - Development activities must be compatible for possibilities and limitation of natural environment and resources. Predevelopmental analysis must... 相似文献