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71.
Four eclipse reappearances of Io were observed with an area-scanning photometer during the 1973 apparition of Jupiter. The results of these observations and of the ones reported in the preceding paper are discussed in the context of recent physical models for posteclipse brightening. An evaluation of the relative merits and deficiencies of all observational techniques which have been used to search for posteclipse brightening of Io leads to the conclusion that the reality of this phenomenon remains very much in doubt. 相似文献
72.
Ocean Dynamics - Die Eisbeobachtungen, die während der Überwinterungen 1941/42 und 1942/43 in dem Lilliehöökfjord gemacht wurden, werden mitgeteilt und daraus der Ablauf der... 相似文献
73.
74.
75.
Franz E. Sueß 《International Journal of Earth Sciences》1921,11(7-8):361-406
Ohne Zusammenfassung 相似文献
76.
77.
Dr. Franz Heritsch 《International Journal of Earth Sciences》1912,3(8):557-572
Ohne Zusammenfassung 相似文献
78.
Franz Ed. Suess 《International Journal of Earth Sciences》1927,18(2):149-154
Ohne Zusammenfassung 相似文献
79.
Investigation of a Tertiary maar structure using three-dimensional resistivity imaging 总被引:1,自引:0,他引:1
Ingolf Brunner Sven Friedel Franz Jacobs & Erik Danckwardt 《Geophysical Journal International》1999,136(3):771-780
This paper presents the application of the electrical resistivity tomography (ERT) method to the investigation of the Tertiary maar structure of Baruth (Germany) known from previous gravimetric surveys. ERT was applied to support the optimum location for a palaeoclimatological drill hole.
Special modifications of data acquisition, signal processing and inversion are introduced to adapt the method of ERT to the special requirements for the 3-D investigation of structures with horizontal extensions of 1 km or more. More than 5000 dipole–dipole combinations were recorded at three concentric circular electrode arrangements using stand-alone transient data acquisition systems (RefTek).
We present a fast approximate imaging technique based on the simultaneous iterative reconstruction technique (SIRT). As the complete calculation of the inverse Frechét matrix is avoided, the algorithm is especially suitable for large data and model spaces, where complete inversion is beyond the limits of available computing hardware. The single-step method is applicable to arbitrary irregular electrode layouts. Synthetic tests show that the imaging procedure reconstructs the main features of the subsurface.
A low-resistivity body could be interpreted as limnic sediments filling the interior of the Tertiary maar crater. Considering the horizontal resistivity gradient, estimates for the lateral and depth extents of the structure were made. An optimum position for a palaeoclimatological borehole was found, and was in good agreement with the gravimetric minimum. 相似文献
Special modifications of data acquisition, signal processing and inversion are introduced to adapt the method of ERT to the special requirements for the 3-D investigation of structures with horizontal extensions of 1 km or more. More than 5000 dipole–dipole combinations were recorded at three concentric circular electrode arrangements using stand-alone transient data acquisition systems (RefTek).
We present a fast approximate imaging technique based on the simultaneous iterative reconstruction technique (SIRT). As the complete calculation of the inverse Frechét matrix is avoided, the algorithm is especially suitable for large data and model spaces, where complete inversion is beyond the limits of available computing hardware. The single-step method is applicable to arbitrary irregular electrode layouts. Synthetic tests show that the imaging procedure reconstructs the main features of the subsurface.
A low-resistivity body could be interpreted as limnic sediments filling the interior of the Tertiary maar crater. Considering the horizontal resistivity gradient, estimates for the lateral and depth extents of the structure were made. An optimum position for a palaeoclimatological borehole was found, and was in good agreement with the gravimetric minimum. 相似文献
80.
Abstract. A total of 1789 fish belonging to 38 families and 73 species were collected at depths between 18 and 1102 m during 216 bottom longline operations off Lanzarote and Fuerteventura, Canary Islands, between February 1994 and December 1995. For each species the depth distribution is provided. Length-weight and depth-size relationships are reported for three shelf-dwelling species. The bigger-deeper relationship found in two of them contrasts with the bigger-shallower pattern of the deeper living trichiurid Lepidopus caudatus . In November 1997, nine additional bottom longline operations were carried out off eastern Fuerteventura at depths between 805 and 1217 m. In this area, after earlier studies in October 1995, a spawning aggregation of the morid Mora moro was encountered for the second time. The catches of 1997 revealed a strongly male-biased sex ratio. Also, the males showed a significantly lower gonadosomal index than two years earlier. These findings indicate slight interannual variations in reproductive timing and an earlier arrival of male Mora moro at the spawning grounds. Clear variations in the number of fish collected at adjacent sites possibly reflect a preference for distinct microhabitats. Preliminary evidence of local upwelling of cold water above the spawning grounds is provided by satellite imagery. 相似文献