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61.
Nikola Stražičić 《GeoJournal》1996,38(4):445-453
Croatia, through its geographic position, is a Mediterranean/Adriatic and Central European/Danube state. As an Adriatic coastal state, it has a long maritime tradition, which is apparent in its well-developed shipping (2.4 million GT), the high-quality ship-building industry (among the top six in the world) and through its numerous sea ports, of which many were established in ancient times. The leading national port is Rijeka, which is at the same time an important transit port for Austria, Hungary, Slovakia and the Czech Republic.The exceptionally indented Croatian Adriatic coast with its attractive archipelagos and favorable climatic and oceanographic conditions in the coastal sea offers very advantageous conditions for comprehensive tourist utilization. This is particularly true of nautical tourism, which is complimented by a larger number of constructed and well-equipped yachting ports/marinas on the coast and islands. 相似文献
62.
The Carpatho-Balkanides and adjacent area: a sector of the Tethyan Eurasian metallogenic belt 总被引:3,自引:1,他引:3
S. Janković 《Mineralium Deposita》1997,32(5):426-433
The Tethyan Eurasian metallogenic belt (TEMB) was formed during Mesozoic and post-Mesozoic times in the area of the former
Tethyan ocean on the southern margin of Eurasia, with the Afro-Arabian and Indian plates to the south. It extends from western
Mediterranean via the Alps and southeastern Europe through the Lesser Caucasus, the Hindu Kush, and the Tibet Plateau to Burma
and SW Indonesia, linking with the West Pacific metallogenic belt. The Carpatho-Balkan region is one of the sectors of the
TEMB, characterized by some specific features. The emplacement of ore deposits is related to a definite time interval, and
to specific tectonic settings such as:
1. Late Permian-Triassic intracontinental rifting along the northern margin of Gondwanaland and/or fragments already separated.
This setting involves volcanogenic and volcano-sedimentary deposits (iron, lead/zinc, manganese, antimony, mercury, barite),
skarn deposits associated with volcano-plutonic complexes of bimodal magmatism, and low temperature carbonate-hosted lead/zinc
deposits.
2. Jurassic intraoceanic rifting – ophiolite complexes: This setting hosts major magmatic (particularly podiform chrome deposits)
and volcano-sedimentary deposits, mainly of the Cyprus type.
3. Subduction-related setting involves porphyry copper deposits, lesser skarn deposits (iron, locally Pb-Zn), massive sulphide
Cu (e.g. Bor) accompanied locally by Pb-Zn of replacement type, epithermal gold deposits, associated with calc-alkaline igneous
complexes of the Early Tertiary-Late Cretaceous, and the Neogene gold/silver and base metals deposits.
4. Post-collision continent-continent setting includes deposits of Pb-Zn, Sb, As, Au-Cu associated with volcano-plutonic complexes
of calc-alkaline affinity.
Several major Alpine metallogenic units are developed in the Carpatho-Balkanides and adjacent area, each characterized by
specific development, mineral associations, and types of ore deposits.
Received: 3 June 1996 / Accepted: 10 January 1997 相似文献
63.
A methodology for improving geopotential models has been developed. Theoretical relations have been derived converting coefficients in harmonic expansions for radial distortions due to geopotential models into geopotential Stokes coefficients. Terms of the order of 10
–10
in magnitude have been retained. 相似文献
64.
J. Keder M. Střižík P. Berger A. Černý P. Engst I. Němcová 《Meteorology and Atmospheric Physics》2004,85(1-3):155-164
Summary Air pollution problem in the Czech Republic is very complex due to large number of factors as turbulent dispersion and chemical reactions concurring in the status of the PBL. For this 3D distribution of pollutants is a key information that cannot be given by conventional monitoring stations. Combined use of DIAL lidar and sodar can give access to such information. Case studies of air pollutants transport are presented using 3D concentration fields of NO2 and ozone measured by lidar and meteorological conditions monitored by Doppler Sodar. 相似文献
65.
An avulsion of the lower Saskatchewan River in the 1870s inundated a large segment of peat-covered floodplain that subsequently has become aggraded with a broad (500 km2) belt of alluvium deposited by the redirected flow. Routing of water and sediment discharge through the avulsion-affected area has been accomplished mainly by networks of sandy bedded anastomosed channels that have formed, evolved, and abandoned as the alluvial belt prograded down the floodplain slope. These processes continue today, though at a much-reduced rate. New channels, formed by crevassing and basinward extension of distributaries, are initially small and shallow, with bottom elevations situated within the avulsive alluvium but above the pre-avulsion peat (floodplain) surface. Subsequent enlargement and downcutting of many of these channels eventually uncovers the underlying peat layer whose resistance to erosion exerts significant influence on cross-sectional shape and further channel development. Peat-floored channels tend to have rectangular cross-sections, high ratios of average to maximum depth (D/Dmax), and a large range of width-to-depth ratios. If the channel continues to enlarge, the peat layer eventually becomes breached, commonly leading to temporarily irregular cross-sections caused by localized scouring at the breach sites. Eventually, the peat layer is completely eroded from the channel floor by undercutting and slumping, after which channel shape becomes governed mainly by other perimeter characteristics. Channels unaffected by peat, either before the peat layer is encountered during early channel development or after it is entirely removed, tend to have low width/depth ratios and a large range of D/Dmax values. 相似文献
66.
67.
Lead-arsenic soil geochemical study as an exploration guide over the Killik volcanogenic massive sulfide deposit, Northeastern Turkey 总被引:3,自引:0,他引:3
A mountainous terrain, the eastern Pontide tectonic belt, located in northeastern Turkey, contains more than 60 known volcanogenic massive sulfide (VMS) deposits that differ in reserves (0.1–30 million tonnes) and grades. Soil geochemistry is conventionally used in exploration programs to discover concealed VMS deposits in the region. In the present study, Pb and As element pair were used as pathfinder elements to investigate the relationship of their anomalies to a completely delineated ore deposit (Killik VMS deposit) in an orientation survey that served as a natural physical model. Two hundred forty soil samples were analyzed in the present study. The two elements, which represent the opposite ends of the mobility range, revealed high contrast and overlapped each other at the location of the ore deposit due to enhancement of the anomalies by hydromorphic dispersion, which is an indication that soil samples would produce reliable results. The successful delineation of the deposit is remarkable considering the rough topography and the climatic limitations. Previously the extremely moist and temperate climate was thought to cause excessive leaching of the trace element pathfinders from the ore deposits to produce extensive anomalies usually extending away from the mineralization thus, leading to erroneous results and/or extensive anomalous areas. But the present research has shown that the method can be used effectively if the sampling and data evaluation is carefully conducted. 相似文献
68.
69.
The response in floodplain respiration of an alpine river to experimental inundation under different temperature regimes
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Tatjana Simčič Nataša Mori Christian Hossli Christopher T. Robinson Michael Doering 《水文研究》2015,29(26):5438-5450
The respiratory potential [i.e. electron transport system activity (ETSA)] of soils and sediments from five floodplain habitats (channel, gravel, islands, riparian forest and grassland) of the Urbach River, Switzerland, and actual respiration rate (R) of the same samples exposed to experimental inundation were measured. Measurements were carried out at three incubation temperatures (4°C, 12°C and 20°C), and ETSA/R ratios (i.e. exploitation of the overall metabolic capacity) were investigated to better understand the effects of temperature and inundation on floodplain functional heterogeneity. Furthermore, ETSA/R ratios obtained during experimental inundation were compared with ETSA/R ratios from field measurements to investigate the exploitation in total metabolic potential at different conditions. Lowest ETSA and R were measured in samples from channel and gravel habitats, followed by those from islands. Substantially higher values were measured in soils from riparian forest and grassland. Both ETSA and R increased with increasing temperature in samples from all habitats, while the ETSA/R ratio decreased because of a rapid response in microbial community respiration to higher temperatures. The metabolic capacity exploitation (i.e. ETSA/R) during experimental inundation was lowest in predominantly terrestrial samples (riparian forest and grassland), indicating the weakest response to wetted conditions. Comparison of experimentally inundated and field conditions revealed that in rarely flooded soils, the metabolic capacity was less exploited during inundation than during non‐flooded conditions. The results suggest high sensitivity in floodplain respiration to changes in temperature and hydrological regime. ETSA/R ratios are considered good indicators of changes in metabolic activity of floodplain soils and sediments, and thus useful to estimate the impact of changes in hydrological regime or to evaluate success of floodplain restoration actions. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
70.