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101.
Underground coal mining activities in Kozlu Hard Coal Basin have reached a level affecting ground layers inside the mining seams and the surface just above the mining operations, causing movements in vicinity of the basin. The movements emerge as collapsing in vertical direction and as sliding, curling and bending in horizontal direction and are termed mining subsidence since they exhibit themselves in ground layers and on earth surfaces in mining environments. These mining-induced movements cause damages and destructions on structures inside and on the surface of mining grounds, and the dimensions of these damages depend upon quality of structures and magnitude of movements. In order to contribute toward a solution to these problems and to mitigate the effects arising during and after mining activities, one should identify and investigate damage prone movements and determine the movement–time relationship. Therefore, it is immensely important to observe, investigate, and measure these movements in regions where mining activities take place. This study focuses on the surface movement-related deformations on the engineering structures in the basin such as Kozlu Seaport and some part of the Zonguldak-Kozlu Road. For this reason, subsidence monitoring points were established on the engineering structures in the basin in a geodetic network concept, and three periods of precise leveling and static GPS observations were conducted. Analyzing these two types of geodetic observations, active and residual subsidence effects were determined for both Kozlu Seaport and the Road nearby. 相似文献
102.
103.
H. Toros A. Deniz L. Şaylan O. Şen M. Baloğlu 《Meteorology and Atmospheric Physics》2005,88(1-2):107-118
Summary Air temperature, absolute humidity and wind speed are the most important meteorological parameters that affect human thermal comfort. Because of heat loss, the human body feels air temperatures different to actual temperatures. Wind speed is the most practical element for consideration in terms of human comfort. In winter, due to the strong wind speeds, the sensible temperature is generally colder than the air temperature. This uncomfortable condition can cause problems related to tourism, heating and cooling. In this study, the spatial and temporal distributions of cooling temperatures and Wind Chill Index (WCI) are analyzed for Turkey, and their effect on the human body is considered. In this paper, monthly cooling temperatures between October and March in the years 1929 to 1990 are calculated by using measured temperature and wind speed at 79 stations in Turkey. The influence of wind chill is especially observed in the regions of the Aegean, west and middle Black Sea and east and central Anatolia. The wind chill in these regions has an uncomfortable effect on the human body. Usually, the WCI value is higher in western, northern and central Anatolia than in other regions. 相似文献
104.
Z. Şen 《Theoretical and Applied Climatology》1997,58(3-4):169-173
Summary Extreme event analysis of meteorological variables by conventional statistical methods does not meet the necessary mathematical assumptions such as the independence of successive occurrences. An alternative method is proposed for analyzing extreme values of dependent variables by considering all the extreme values above a threshold value in finite samples. The probability for the maximum event in a given finite sequence of dependent meteorological variables is derived explicitly.With 1 Figure 相似文献
105.
Summary Regional dry and wet spell durations within a 15 year period are mapped for the southwestern part of Saudi Arabia for summer and winter. If the number of spells is plotted versus duration a straight-line results on semi-logarithmic paper for most stations. However, a few stations exhibit two or three different slopes showing the effect of local climate. Simple regression equations are proposed for the dry or wet spell duration at any station allowing the mapping of regional variation for the entire study area. Such maps are useful tools in the assessment of the spatial and/or temporal wet and dry period duration for the area between stations. Similar maps could be developed for other parts of the world.With 10 Figures 相似文献
106.
107.
Sinan Şahin Murat Türkeş Sheng-Hung Wang David Hannah Warren Eastwood 《Climate Dynamics》2015,45(11-12):3381-3401
108.
Zekai Şen Hussam A. Khiyami Saad G. Al-Harthy Faisal A. Al-Ammawi Ali B. Al-Balkhi Mohammed I. Al-Zahrani Hashim M. Al-Hawsawy 《Arabian Journal of Geosciences》2013,6(9):3563-3572
Flood inundation maps are dependent on the topographic and geomorphologic features of a wadi (drainage basin) in arid regions, which are most susceptible for potential flash flood occurrences, such as in the southwestern part of the Kingdom of Saudi Arabia. It is not possible to control the potential flood hazards by using only technological instruments that forewarn the occurrences or imminence. Additionally, it would be better to prepare flood risk maps so as to delineate the risky areas to educate the administrators and local settlers. The availability of these maps is the key requirement for any urban development that entails land use allocation, identification of dam, tunnel, highway, bridge sites, and infrastructure locations for sustainable future. This paper suggests the necessary steps in flood inundation map preparation after determining the possible flood discharge. For this purpose, a set of critical cross-sections along the possible flood plain are taken in the field with surveying methods and measurements. The calculation of the average flow velocity in each section is calculated according to the cross-section geometric, hydraulic, and material properties. Synthetic rating curves (SRC) are prepared for each cross section, which are very useful especially in arid and semi-arid regions where there are no perennial surface water flows for natural rating curve measurements. All the SRCs appear in the form of power function which relates the flow depth to discharge in a given cross section. It is then possible to calculate the flood depth in the cross section through its SRC. Depending on the cross-section shape, the flood width can be calculated. The connection of a series of widths on a scaled topographic map delineates the flood inundation area. If digital elevation map (DEM) is available, then the SRCs can be integrated with these maps and the flood inundation delineation can be achieved automatically. Since DEMs are not available, the topographic maps are used for this purpose in order to delineate flood inundation areas within wadis Hali and Yiba from the southwestern Kingdom of Saudi Arabia. 相似文献
109.
110.
Dr. A. M. Celâl Şengör 《International Journal of Earth Sciences》1985,74(2):181-213
Zusammenfassung Das Alpen-Himalaja-System besteht, zwischen den Karpaten und der pazifischen Küste Asiens, aus zwei voneinander unabhängigen, aber einander weitgehend überlagernden orogenen Komplexen. Der hier Kimmeriden genannte ältere Komplex ist durch die Destruktion der Paläo-Tethys, des ursprünglichen, sich nach Osten erweiternden Pangäagolfes zwischen Laurasien und dem Kimmerischen Kontinent in einem Intervall zwischen dem Unterkarbon und Unterkreide entstanden. In seiner Geschichte sind auch die kontinentalen Blöcke von Nord- und Südchina und Annamia sowie eine Anzahl von viel kleineren Fragmenten beteiligt gewesen. Der jüngere, hier als Alpiden bezeichnet, ist durch die Subduktion der Neo-Tethys und örtliche Kollision verschiedener Teile des zersplitterten Gondwana-Landes mit Eurasien zwischen dem Oberjura und der Gegenwart zustandegekommen. Wo die ursprüngliche Breite des Kimmerischen Zwischenkontinents klein war, besteht heute eine fast vollständige Überlagerung der Kimmeriden durch die Alpiden, wobei die Erkennung der ersteren sehr erschwert ist. In Regionen, wo bedeutende Kontinentalstücke zwischen den beiden Orogenkomplexen vorkommen, sind sie leicht voneinander unterscheidbar. Die Kimmeriden enthalten ein geflochtenes Narbennetz, entlang welchem Ozeanschließung zu verschiedenen Zeiten stattfand. Die kimmeridischen Kollisionen haben auch ein ausgedehntes kratonisches Deformationsfeld zwischen dem Dnjepr-Donetz-Becken südöstlich Europas und dem östlichen Sibirien ins Leben gerufen, das durch Horizontalverschiebungen, Zerrungs- und Pressungsbecken und »Inversionen« verschiedenen Stils gekennzeichnet ist. Einige dieser Strukturen waren posthum in bezug auf ältere und viele haben die Platznahme späterer Strukturen der Alpiden stark beeinflußt. Diese Sachlage hat den Anschein langlebiger bodenständiger Strukturen erzeugt, was in der Tat der Ausdruck verschiedener, voneinander ganz unabhängiger, aber gleichorientierter Verformungsfelder zu sein scheint und mit den Strukturen selbst nicht viel zu tun hat. Die Kimmeriden scheinen gewaltige »orogenic Collages« zu enthalten und viel komplizierter als die Alpiden zu sein. Diese orogenen Collages enthalten viele exotische Blöcke panthalassischer Herkunft und große Areale von Akkretionskomplexen auf ozeanischem Boden, wie derjenige des Songpan-Ganzi-Systems in China. Die Erkennung einer »verdoppelten« Geschichte der Tethys führt uns zu einem verbesserten Verständnis der Tektonik nicht nur des Tethysraumes, sondern ganz Eurasiens.
Diese Arbeit ist meinem lieben und verehrten, vor drei Jahren nach fruchtbarster Arbeit durch den Tod entrissenen Freund Prof. Dr. J. Hennig Illies als ein Zeichen meiner Dankbarkeit gewidmet. 相似文献
The Alpme-Himalayan-System consists, between the Carpathians and the Asiatic shores of the Pacific, of two independent, but largely superimposed orogenic complexes. The older complex, here called theCimmerides, formed between the early Carboniferous and the early Cretaceous by the destruction of Palaeo-Tethys, the original, eastwards-widening gulf of Pangaea between Laurasia and the Cimmerian Continent. The continental blocks of North and South China and Annamia, as well as a number of much smaller fragments also participated in its history. The younger one, here designated theAlpides, formed between the late Jurassic and the present by subduction of Neo-Tethys and, locally, by the collision with Eurasia of various fragments of the dispersed Gondwana-Land. Where the original width of the Cimmerian Continent had been small, the superposition of the Cimmerides by the Alpides was nearly complete and the recognition now of the former is therefore very difficult. In regions, where the width of continental pieces lying between the two orogenic complexes is large, both can be distinguished easily. The Cimmerides contain a multi-strand suture network along which ocean closure occured at different times. Cimmeride collisions also generated a vast field of cratonic deformations between the Dnyepr-Donets basin in southeastern Europe and eastern Siberia that is characterised by strike-slip faults, both extensional and compressional basins, and various kinds of >inversion< structures. Some of these structures nucleated on older ones and many also localised the later Alpide structures. This has given the impression of the existence of >autochthonous<, long-lived structures, although every >reactivation< event was the result of entirely independent but similarly-orientated strain fields whose origins had little to do with the structures themselves. The Cimmerides seem to be a more complicated orogenic system than the Alpides, involving large >orogenic collages< probably containing numerous exotic blocks of Panthalassan origin and large areas of accretionary complexes on oceanic substratum, such as that of Songpan-Ganzi of China. The recognition of a >double< history of Tethys leads to a better understanding of the tectonics not only of the Tethyan area, but also of entire Eurasia.
Résumé Le système Alpes-Himalaya se compose, entre les Car-pathes et la côte pacifique de l'Asie, de deux complexes orogéniques indépendants l'un de l'autre, mais largement superposés l'un à l'autre. Le plus ancien complexe, appelé ici lesCimmérides, s'estformé entre le Carbonifère inférieur et le Crétacé inférieur lors de la disparition de la Paléo-Téthys, c'est-à-dire du golf équatorial Permo-Triassique de la Pangée compris entre la Laurasie et le Continent Cimmérien. Dans ce développement sont également impliqués les blocs continentaux de la Chine septentrionale, de la Chine méridionale, de l'Annamia, ainsi qu'un certain nombre de fragments beaucoup plus petits. Par ailleurs, le complexe plus récent, appelé ici lesAlpides, s'est formé entre le Jurassique supérieur et la période actuelle par la subduction de la Néo-Téthys et des collisions locales de morceaux épars du continent de Gondwana avec l'Eurasie. Là où la largeur initiale du continent cimmérien était faible, on trouve aujourd'hui une superposition complète des deux complexes orogéniques, ce qui rend très difficile la mise en évidence du système le plus ancien. Au contraire, là où des blocs continentaux importants séparent les deux orogènes, leur distinction est facile. Les Cimmérides sont caractérisées par un réseau de sutures multiples, témoin des fermetures océaniques qui se sont produites à différentes époques. Les collisions cimmérides ont également donné lieu à un vaste champ de déformations cratoniques entre le bassin du Dnieper-Donetz (Europe du Sud-Est) et la Sibérie orientale. Ces déformations consistent en décrochements, en bassins d'extension ou de compression et en inversions de divers styles. Certaines de ces structures ont pris naissance de manière posthume sur des structures antérieures, et bon nombre d'entre elles ont à leur tour influencé la localisation des structures des Alpides. Cet état de choses a pu faire croire à l'existence de structures »autochtones« jouant pendant de longues durées; en fait leurs réactivations sont l'efet de champs de déformations successifs, indépendants. l'un de l'autre, mais d'orientation commune, et dont l'origine n'a pas grand chose à voir avec les structures elles-mêmes. Les Cimmérides semblent comporter de gigantesques »collages« orogéniques et, de ce fait, sont plus compliquées que les Alpides. Ces collages orogéniques contiennent beaucoup de blocs exotiques d'origine panthalassique et de grands domaines de complexes d'accrétion sur fond océanique, tel le système Songpan-Ganzi en Chine. La mise en évidence d'une double histoire de la Téthys conduit à une meilleure connaissance de la tectonique non seulement du domaine téthysien, mais aussi de toute l'Eurasie.
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Diese Arbeit ist meinem lieben und verehrten, vor drei Jahren nach fruchtbarster Arbeit durch den Tod entrissenen Freund Prof. Dr. J. Hennig Illies als ein Zeichen meiner Dankbarkeit gewidmet. 相似文献