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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.
Alessandro Beghini Zdeněk P. Bažant R. Chambon D. Kolymbas I. Herle 《国际地质力学数值与分析法杂志》2004,28(4):365-372
66.
67.
潮水盆地铀成矿水文地球化学研究 总被引:1,自引:0,他引:1
在分析潮水盆地自然地理、地质背景及水文地质特征的基础上,对盆地铀成矿水文地球化学特征进行了探讨。结果表明:潮水盆地为-渗入型自流水盆地,其深层地下水中铀存在形式为UO2(CO3)n^2-2n。;从盆地边缘到盆地中心具有明显从氧化环境到还原环境的水文地球化学分带特征,水中铀经历了由溶滤迁移到还原沉淀的矿化过程;在盆地北缘的照壁山-白芨芨、阿右旗-陶家井地区,西南部的平易-平山湖地区具备十分有利的铀成矿条件和良好的铀成矿远景。 相似文献
68.
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
69.
Mesozooplankton spatial distribution and community structure in the South Adriatic Sea during two winters (2015, 2016) 下载免费PDF全文
Whereas the data on mesozooplankton in the epipelagic offshore Mediterranean Sea are extensive, less information is available about plankton in the deeper layers. The present study aims to describe the vertical and horizontal structure and distribution of mesozooplankton species and their associations down to 1,200 m in the water of the Southern Adriatic Sea. Zooplankton were sampled using a Nansen net of 200‐μm mesh size during two cruises in the winters of 2015 and 2016, extending from the coast to the open sea. In total, 203 zooplankton taxa were identified. The community was dominated by copepods, representing between 67% and 91% of the total abundance. The highest total densities were recorded in the upper layers where a high proportion (up to 36%) of appendicularians was also observed in the first sampled year. Five groups of samples were determined based on their community structure. In 2015 communities were distinct between the 0 and 50 m layer and the underlying one (50–100 m), whereas in 2016 epipelagic waters were inhabited by a more uniform mesozooplankton community. The mesopelagic and deep‐water fauna, especially copepods, showed a relatively stable composition in both sampling years Overall, our study confirms the oligotrophic character of the Southern Adriatic, with occasional density outbreaks of appendicularians under favourable conditions. 相似文献
70.
The response in floodplain respiration of an alpine river to experimental inundation under different temperature regimes 下载免费PDF全文
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