Supermassive black hole growth and merger rates from cosmological N-body simulations     

Miroslav Micic  Kelly Holley-Bockelmann  Steinn Sigurdsson  Tom Abel 《Monthly notices of the Royal Astronomical Society》2007,380(4):1533-1540

  相似文献   

Depth-Recursive Tomography of the Bohemian Massif at the CEL09 Transect—Part A: Resolution Estimates and Deblurring Aspects     

Miroslav Novotný 《Surveys in Geophysics》2011,32(6):827-855

The refraction CEL09 profile from the CELEBRATION 2000 project intersects the main terranes of the Bohemian Massif in the NW–SE direction: the Saxothuringian, the Teplá-Barrandian, the Moldanubian and the Moravo-Silesian. In its easternmost part, it crosses the Western Outer Carpathians overthrust westward onto the Bohemian Massif. Only the first 450 km were surveyed with the densest deployment of shot points providing data suitable for a reliable geological interpretation. The first-arrival depth-recursive tomography was applied here to derive a P-wave velocity image of the upper and middle crust (Part A). The proper interpretation of the obtained velocity features is the subject of the accompanying paper (Part B). The attained resolution in the velocity image is shown to be superior as compared with the previous CEL09 models based also on the more uncertain later arrivals of reflection waves. The applied DRTG (depth-recursive tomography on grid) method is based on a regular network of refraction grid rays generated for iteratively updated starting models. Only the distinct first arrivals with minimum uncertainty are used for the DRTG inversions to yield the maximum resolution. Thanks to the full control of the data fit by the grid rays used, the statistical lateral resolution could be determined at single grid depths for the chosen confidence levels. Thus, the lateral sizes of the anomalies that can be yet resolved are determined in dependence on their depths and their velocity excesses. The defocusing of the imaged features is studied on the basis of the spatial responses to spike excitation. The calculated spatial responses also allowed the edge smearing of the velocity anomalies to be assessed. Special attention is paid to the imaging of low-velocity zones that are usually suppressed by the smoothing measures used in standard tomographic methods. An improvement was achieved if the smoothing was suggested with regard to the occurrence of the low-velocity zones repeatedly appearing in higher iterations. The gained deblurring effect concerns both the negative and positive anomalies as documented on the velocity features interpreted in the accompanying paper.  相似文献   

Radio-continuum study of the nearby Sculptor group Galaxies. Part 2: NGC 55 at λ=20, 13, 6 and 3 cm     

Andrew N. O’Brien  Miroslav D. Filipović  Evan J. Crawford  Nicholas F. H. Tothill  Jordan D. Collier  Ain Y. De Horta  Graeme F. Wong  Danica Drašković  Jeff L. Payne  Thomas G. Pannuti  Jared P. Napier  Stephen A. Griffith  Wayne D. Staggs  Srdjan Kotuš 《Astrophysics and Space Science》2013,347(1):159-168

A series of new radio-continuum (λ=20, 13, 6 and 3 cm) mosaic images focused on the NGC 55 galactic system were produced using archived observational data from the Australia Telescope Compact Array. These new images are both very sensitive (down to rms=33 μJy) and feature high angular resolution (down to <4″). Using these newly created images, 66 previously unidentified discrete sources are identified. Of these sources, 46 were classified as background sources, 11 as H?ii regions and 6 as supernova remnant candidates. This relatively low number of SNR candidates detected coupled with the low number of large H?ii regions is consistent with the estimated low star formation rate of the galaxy at 0.06 M _⊙?year^?1. Our spectral index map shows that the core of galaxy appears to have a shallow spectral index between α=?0.2 and ?0.4. This indicates that the core of the galaxy is a region of high thermal radiation output.  相似文献   

Hydrogeological pattern of groundwater flow of landslides in Cretaceous claystones based on long-term groundwater monitoring and hydrologging measurement   总被引：1，自引：0，他引：1  

Jan Novotný  Miroslav Kobr 《Environmental Geology》2009,58(1):25-32

Long-term groundwater monitoring has been carried in the model locality of the landslide area at Třebenice, situated in the northern part of the Czech Republic in Cretaceous claystones to marlstones. Primarily, long-term fluctuation of the groundwater and piezometric levels has been monitored. Monitoring of groundwater flow was carried out in selected wells also by the photometry logging method using a dilution technique of a marked liquid. On the basis of these results, the pattern of the groundwater flow through the landslide area was determined in lithologically homogeneous Cretaceous claystones to marlstones. Interpretation of monitoring results indicated that water flows preferentially through the zone of near-surface loosening of the claystone rock massif, in general parallel to the slope inclination between 8 and 10-m depth below ground level. This zone exhibits a higher permeability given by 1–2 orders of hydraulic conductivity compared with overlying strata and underlying rock in which this zone is closed. This verified pattern of groundwater flow has a significant effect on the stability of the sliding slope and it is one of the main factors affecting the evolution of landslides on the slopes formed by these rocks.  相似文献   

Well logging methods in groundwater surveys of complicated aquifer systems: Bohemian Cretaceous Basin     

Josef V. Datel  Miroslav Kobr  Martin Prochazka 《Environmental Geology》2009,57(5):1021-1034

  相似文献   

Probabilistic depth–damage curves for assessment of flood-induced building losses     

McGrath  Heather  Abo El Ezz  Ahmad  Nastev  Miroslav 《Natural Hazards》2019,99(1):1-16

Natural Hazards - To investigate the propagation of meteorological droughts to agricultural and hydrological droughts, the relationship between droughts was analyzed using observed precipitation...  相似文献   

A palaeomagnetic and petromagnetic study of Upper-Carboniferous,Permian and Triassic sediments,NW Bulgaria     

Peter Nozharov  Nikolai Petkov  Slavcho Yanev  Vladimír Kropáček  Miroslav Krs  Petr Pruner  Reviewer J. Pícha 《Studia Geophysica et Geodaetica》1980,24(3):252-284

Summary In order to obtain basic palaeomagnetic data on Upper Carboniferous, Permian and Triassic sediments collected from the NW Bulgaria, laboratory stability tests were extended from A.C. and thermal treatments to studies of mineral phase changes and to investigations of changes of magnetic anisotropy during laboratory procedures. Laboratory criteria were found which permitted to distinguish samples suitable for palaeomagnetic analyses from those representing rocks totally or almost totally chemically reworked during their history. Palaeomagnetic directions and pole positions derived from Stephanian, Lower Permian and Triassic rocks from the southern margin of the Moesian Platform are compatible with the values obtained for the tectonically stable North-European Platform.  相似文献   

Saxonische Tektonik der Böhmischen Masse     

Dr. Miroslav Malkovský CSc. 《International Journal of Earth Sciences》1976,65(1):127-143

Zusammenfassung Die saxonische Tektonik beeinflußte nach dem Abschluß der variszischen Gebirgsbildung wesentlich die tektonische Entwicklung der Böhmischen Masse, die zu einem konsolidierten Block von Hebungstendenz wurde. Die saxonische Tektogenese der Böhmischen Masse stellt vor allem ein Abbild der tektonischen Entwicklung der alpinkarpatischen Geosynklinale im Meso- und Känozoikum dar. Orogenetische Bewegungen der alpin-karpatischen Geosynklinale beeinflußten unmittelbar die Tektonik in der Böhmischen Masse.Das Mesozoikum stellte in der Böhmischen Masse eine Zeitperiode lediglich mit Bruchtektonik, ohne Vulkanismus dar. Die mesozoischen tektonischen Strukturen der Böhmischen Masse werden durch tektonische Elemente von nordwest-südöstlicher Streichrichtung charakterisiert. Im Känozoikum kommen in der Böhmischen Masse zum Unterschied vom Mesozoikum richtungsmäßig unterschiedliche Strukturen zum Vorschein, nämlich Brüche von südwest-nordöstlicher Streichrichtung, die für das untere Miozän charakteristisch sind und dem jüngeren Strukturplan des Westabschnittes der tschechoslowakischen äußeren Karpaten entsprechen. Ferner Brüche, die von NW nach SO und NNW nach SSO streichen und für das Pliozän charakteristisch sind. Für das Känozoikum sind auch drei Phasen des basischen Vulkanismus in der Zeitperiode vom Anfang zum Ende des Neogens bedeutsam. Die heutzutage auf der Erdoberfläche bemerkbaren Brüche stellen meistens Äußerungen der Bewegungen einzelner Schollen im Neogen und Quartär dar. Die Sprunghöhe der Bewegungen erreicht mehr als 1000 m.

---

The Saxonic block-fault tectonics influenced substantially the tectonic development of the Bohemian Massif after the end of the Variscan orogeny, when the Bohemian Massif has become a consolidated block with a rising tendency. The Saxonic blockfault tectogenesis of the Bohemian Massif is mainly a reflexion of the tectonic development of the Alpine-Carpathian geosyncline in the Mesozoic and Cenozoic. Orogenic movements of individual orogenic phases in the Alpine-Carpathian geosyncline directly influenced tectonic movements in the Bohemian Massif. The Mesozoic was for the Bohemian Massif (after the preceding Variscan orogeny) a period with only fault tectonics, without any volcanic activity. Mesozoic tectonic structures of the Bohemian Massif are characterized by tectonic elements of NW-SE direction. Structures differing in direction from those in the Mesozoic apply in the Bohemian Massif in the Cenozoic. They are faults of the SW-NE direction characteristical for the Lower Miocene, which correspond to the younger structural plan of the Czechoslovak Inner Carpathians western section, and further faults of the NW-SE and NNW-SSE direction characteristical for the Pliocene. For the Cenozoic also three phases of basic volcanism in the period from the beginning to the end of Neogene are significant. Faults visible at present on the surface are mostly a consequence of movements of individual blocks during the Neogene and the Quaternary. The magnitude of movements reaches more than 1000 m.

---

Résumé La tectonique saxonienne a influencé essentiellement le développement tectonique du Massif de Bohême après la fin de l'orogenèse varisque qui le consolida en un bloc à tendance ascendante. La tectogenèse saxonienne du Massif de Bohême est avant tout le reflet du développement tectonique du géosynclinal alpino-carpatique au cours du Mésozoïque et du Cénozoïque, dont les mouvements orogéniques l'ont directement influencé. Le Mésozoïque représente seulement une ère de tectonique de failles sans activité volcanique, avec des structures tectoniques caractérisées par une direction NW-SE. Au Cénozoïque, par contre, des structures de directions différentes apparaissent, principalement des structures SW-NE qui sont caractéristique pour le Miocène inférieur, correspondant au plan structural de la partie occidentale des Carpates tchécoslovaques externes. D'autres failles, de direction NW-SE et NNW-SSE, sont caractéristiques pour le Pliocène. Sont également significatifs pour le Cénozoïque trois phases de volcanisme basique durant la période s'étendant du commencement à la fin du Néogène. Les failles aujourd'hui observables sont généralement l'expression de mouvements individuels de blocs au Néogène et au Quaternaire. L'ampleur des rejets liés à ces mouvements atteint plus de mille mètres.

---

, . - . . . - — . , , : - — , , - — - - — --, . , . , , . . . .

  相似文献   

Geomagnetic field intensity during the Plio-Pleistocene derived from the thermo-remanence of porcellanites and palaeo-slags (Czechoslovakia)     

Miroslav Krs 《Pure and Applied Geophysics》1968,69(1):158-167

Summary The present paper deals with the derivation of the intensity of the geomagnetic field in the Plio-Pleistocene, Central Europe. The intensity was derived from the thermo-remanence of porcellanites and palaeo-slags. These rocks represent a common product of intense thermal alteration of loams due to spontaneous combustion of coal seams. Porcellanites and palaeo-slags show outstanding palaeomagnetic properties, their remanent magnetization is of thermo-remanent origin and they were mineralogically stabilized under natural conditions in the geological past, during the coal combustion. It was found, that the intensity of the geomagnetic field during the Plio-Pleistocene oscillated about the value of the present-day intensity.  相似文献   

Ferromagnetismus des Kassiterits und seine lagerstättenkundliche Bedeutung     

Václav Hanuš  Miroslav Krs 《Mineralium Deposita》1966,1(2):139-147

  相似文献