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311.
N. Richter 《Astronomische Nachrichten》1980,301(6):301-304
Aus dem Tautenburger Katalog von 745 kompakten Galaxien in 4 Feldern um M3 wurden blaue Objekte selektiert. Dies geschah mit Hilfe des Farbenindex U – B ≧ −0.40 mag und durch spektroskopische Inspektion auf Objektivprismen-aufnahmen. Es wurden 45 Objekte als blau oder als emissionsverdächtig befunden. 相似文献
312.
G. M. Richter 《Astronomische Nachrichten》1976,297(3):145-146
Contrary to the number-magnitude relation, the number-angular diameter relation is influenced by the luminosity function. The number-diameter counts by DODD et al. (1975) are in agreement with the normal luminosity function and a homogeneous space distribution without a local density excess. Almost all the faint small (<18 arcsec) galaxies may be first-ranked cluster members. 相似文献
313.
This paper explains that the terms"horizontal and vertical scales"are not appropriate in map projections theory. Instead, the authors suggest using the term"sca... 相似文献
314.
G. A. Richter 《Astronomische Nachrichten》1970,292(1):9-16
The Bernoullian statistics give for rare types of variable stars only inaccurate results concerning the probability of discovery p. In these cases p may be reasonably calculated by means of the „Quality Function”︁ Q(Δm, m), defined by Borgman. Q(Δm, m) is the probability of the discovery of a magnitude difference Δm near the apparent magnitude m. Three methods are discussed which allow to find Q(Δm, m). An application to the Sonneberg material shows, as expected, that Q(Δm, m) will become smaller with Δm decreasing and m increasing. Moreover the psychologically interesting fact, already supposed by Borgman, is confirmed that even well-trained observers will overlook about 10% of all large magnitude differences < 1 mag in using the blink-, stereo- or electronic scanning method for the discovery of variable stars. 相似文献
315.
316.
Žukovič Milan Borovský Michal Lach Matúš Hristopulos Dionissios T. 《Mathematical Geosciences》2020,52(1):123-143
Mathematical Geosciences - A novel Gibbs Markov random field for spatial data on Cartesian grids based on the modified planar rotator (MPR) model of statistical physics has been recently introduced... 相似文献
317.
318.
Salt-water discharges from a fault system in the crystalline basement of the Black Forest into the gravel aquifer of the
Kinzig River valley near Ohlsbach, upper Rhine River valley, southwestern Germany. The salt water (TDS, 16 g/kg) ascends from
a reservoir at 1 3 km depth. Once discharged into the gravel aquifer, the saline deep water mixes with fresh groundwater
and is carried along the groundwater flow path to the middle of the Rhine River valley. There, the natural geogene salt-water
plume merges with a man-made chloride-rich infiltration zone along the Rhine River. The plume was mapped using (1) chloride
data from groundwater observation wells, and (2) resistivity data from geoelectric sounding. Background chloride is about
7 mg/kg. In the central region of the plume, chloride concentration exceeds 200 mg/kg. A continuous area of Cl 1 50 mg/kg
is distinguished from the discharge fault to the Rhine River over a distance of 12 km. Resistivities range from 1 50 Ω in
uncontaminated regions to <7 Ω in the 700 m-long central region of the plume. A low resistivity plume (7–10 Ω) stretches for
1 7 km into the Rhine River valley. The two plume maps are in good agreement.
Received, April 1998 / Revised, November 1998, January 1999 / Accepted, January 1999 相似文献
319.
This paper describes late Cambrian dikes and Early Ordovician volcano-sedimentary successions of the Prague Basin, Bohemian Massif, to discuss the timing and kinematics of breakup of the northern margin of Gondwana. Andesitic dikes indicate minor E–W crustal extension in the late Cambrian, whereas the Tremadocian to Dapingian lithofacies distribution and linear array of depocenters suggest opening of this Rheic Ocean rift-related basin during NW–SE pure shear-dominated extension. This kinematic change was associated with the onset of basic submarine volcanism, presumably resulting from decompression mantle melting as the amount of extension increased. We conclude from these inferences and from a comparison with other Avalonian–Cadomian terranes that the rifting along the northern Gondwana margin was a two-stage process involving one major pulse of terrane detachment in the early Cambrian and one in the Early Ordovician. While the geodynamic cause for the former phase remains unclear, but still may include effects of Cadomian subduction (roll-back, slab break-off), isostatic rebound, or mantle plume, the incipient stage of the latter phase may have been triggered by the onset of subduction of the Iapetus Ocean at around 510 Ma, followed by advanced extension broadly coeval (Tremadocian to Darriwilian) in large portions of the Avalonian–Cadomian belt. Unequal amounts of extension resulted in the separation and drift of some terranes, while other portions of the belt remained adjacent to Gondwana. 相似文献
320.
Priv.-Doz. Dr. Dieter Richter 《International Journal of Earth Sciences》1968,57(2):424-445
Five movement-phases during the Variscan tectogenesis shaped the structural cast of the Devonian rocks in South Devon. The first movement-phase, i. e. the main tectonic phase, resulted in the mappable fold system trending E-W or ENE-WSW in the west accompanied by related minor folds, and the first cleavage (s 1) parallel to the axial planes. The cleavage planes dip to the south as far as the line Slapton-Bigbury, while farther to the south they dip to the north and finally to the south again, thus forming a huge fanning. In the second movement-phase a second cleavage (s 2) with E-W strike associated with minor folds, was superimposed on the older structures south of the line Berry Head-Cornworthy. The trend of these folds is, more or less E-W. Furthermore the second cleavage shows a fanning which does not coincide with that of the first cleavage. South-vergent minor folds of bedding and cleavage planes, associated with small-scale southward thrusts represent structures of a third movement-phase. The fourth movement-phase was the kinking of mainly the first cleavage in the southern part of South Devon. There are two groups: one shows flat-lying kink-bands affecting mainlys 1; seldoms 2, and having a southward thrusting sense of movement while the other consists of nearly vertical kink-bands trending N-S which displace to the south on their eastern sides. Subsequently with the commencement of the New Red deposition, repeated tectonic stretching took place, resulting in N-S and WSW--ENE trending faults. The succession of the different tectonic events led to occasionally very complicated superimpositions. The rocks in the middle and southern part of South Devon suffered a regional metamorphosis that increases slowly towards the south. Finally, the tectonic structures of South Devon are compared with those in South Cornwall where the same movements-phases caused a completely different structural style. 相似文献