Secular perturbation theory and computation of asteroid proper elements     

Andrea Milani  Zoran Knežević 《Celestial Mechanics and Dynamical Astronomy》1990,49(4):347-411

A new theory for the calculation of proper elements, taking into account terms of degree four in the eccentricities and inclinations, and also terms of order two in the mass of Jupiter, has been derived and programmed in a self contained code. It has many advantages with respect to the previous ones. Being fully analytical, it defines an explicit algorithm applicable to any chosen set of orbits. Unlike first order theories, it takes into account the effect of shallow resonances upon the secular frequencies; this effect is quite substantial, e.g. for Themis. Short periodic effects are corrected for by a rigorous procedure. Unlike linear theories, it accounts for the effects of higher degree terms and can thus be applied to asteroids with low to moderate eccentricity and inclination; secular resonances resulting from the combination of up to four secular frequencies can be accounted for. The new theory is self checking : the proper elements being computed with an iterative algorithm, the behaviour of the iteration can be used to define a quality code. The amount of computation required for a single set of osculating elements, although not negligible, is such that the method can be systematically applied on long lists of osculating orbital elements, taken either from catalogues of observed objects or from the output of orbit computations. As a result, this theory has been used to derive proper elements for 4100 numbered asteroids, and to test the accuracy by means of numerical integrations. These results are discussed both from a quantitative point of view, to derive an a posteriori accuracy of the proper elements sets, and from a qualitative one, by comparison with the higher degree secular resonance theory.  相似文献   

Geohazards assessment and mapping of some Balkan countries   总被引：1，自引：0，他引：1  

Betim Mu?o  Georgi Alexiev  Shyqyri Aliaj  Zenun Elezi  Bogdan Grecu  Neculai Mandrescu  Zoran Milutinovic  Mircea Radulian  Boyko Ranguelov  Defrim Shkupi 《Natural Hazards》2012,64(2):943-981

The assessment of geological hazard is a topic with significant interest for the Balkans. During the last decade of twentieth century, most of the countries in the region have embarked on the road of a hasty transitory period from totalitarian regimes to democracy. Development of free market economy has given rise to uncontrolled movement of people, fast construction of housing and facilities and unproportioned accumulation of population around and in big cities. Besides Greece, an old member of European Union, and two newcomers in the organization, Romania and Bulgaria, the other countries are all hoping to enter the Union as faster as they can. Many different candidate or full-fledged member country programs of European Community offer a lot of joint and cross-border projects for constructing road infrastructure and facilities. As development accelerates in the Balkans and given the intensive geohazard elements that this territory exhibits, it becomes increasingly important to understand, study, and map these elements for being aware of the damage to the total environment these hazards might cause. The geohazard map and assessment of some Balkan countries has been carried out through two scientific meetings in Ohrid, Macedonia, and Tirana, Albania during 2007. The map is compiled in the Albanian Geological Survey, Tirana, Albania in the scale 1:1,000,000. As a base map, we used the topographic map produced by VGI, formerly Yugoslavia mapping authorities. As a seismic layer in our map, we used the values of peak ground acceleration obtained from Global Seismic Hazard Assessment Program. Two catalogs were constructed: The first one that contains the crustal earthquakes (hypocentral depth within first 70?km) and the second one that contains intermediate earthquakes (hypocentral depth below 70?km). This work is largely based on previous studies and investigations by earth scientists and specialists of each country comprised in this territory. In this respect, the map we constructed should be considered as a preliminary composite geohazard map with the possibility to be enriched and added with other new elements and data in the future.  相似文献   

The World Karst Aquifer Mapping project: concept,mapping procedure and map of Europe     

Chen  Zhao  Auler  Augusto S.  Bakalowicz  Michel  Drew  David  Griger  Franziska  Hartmann  Jens  Jiang  Guanghui  Moosdorf  Nils  Richts  Andrea  Stevanovic  Zoran  Veni  George  Goldscheider  Nico 《Hydrogeology Journal》2017,25(3):771-785

Karst aquifers contribute substantially to freshwater supplies in many regions of the world, but are vulnerable to contamination and difficult to manage because of their unique hydrogeological characteristics. Many karst systems are hydraulically connected over wide areas and require transboundary exploration, protection and management. In order to obtain a better global overview of karst aquifers, to create a basis for sustainable international water-resources management, and to increase the awareness in the public and among decision makers, the World Karst Aquifer Mapping (WOKAM) project was established. The goal is to create a world map and database of karst aquifers, as a further development of earlier maps. This paper presents the basic concepts and the detailed mapping procedure, using France as an example to illustrate the step-by-step workflow, which includes generalization, differentiation of continuous and discontinuous carbonate and evaporite rock areas, and the identification of non-exposed karst aquifers. The map also shows selected caves and karst springs, which are collected in an associated global database. The draft karst aquifer map of Europe shows that 21.6% of the European land surface is characterized by the presence of (continuous or discontinuous) carbonate rocks; about 13.8% of the land surface is carbonate rock outcrop.

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Mineralogical and geochemical characteristics of Miocene pelitic sedimentary rocks from the south-western part of the Pannonian Basin System (Croatia): Implications for provenance studies     

Anita Grizelj  Zoran Peh  Darko Tibljaš  Marijan Kovačić  Tomislav Kurečić 《地学前缘(英文版)》2017,8(1):65-80

Fifty-two samples of Miocene pelitic sedimentary rock from outcrops on Medvednica,Moslavacka Gora and Psunj Mts.,and boreholes in the Sava Depression and the Pozega Sub-depression were investigated.These sediments formed in different marine(with normal and reduced salinity),brackish,and freshwater environments,depending on the development stage of the Pannonian Basin System.Carbonate minerals,clay minerals and quartz are the main constituents of all pelitic sedimentary rocks,except in those from Moslavacka Gora Mt in which carbonate minerals are not present.Feldspars,pyrite,opal-CT,and hematite are present as minor constituents in some rocks.Besides calcite,dependent on the sedimentary environment and diagenetic changes,high-magnesium calcite,aragonite,dolomite and ankerite/Cadolomite are also present.Smectite or illite-smectite is the main clay minerals in the samples.Minor constituents,present in almost all samples,are detrital illite and kaolinite.In some samples chlorite is also present in a low amount.Major elements,trace elements and rare earth elements patterns used in provenance analysis show that all analysed samples have a composition similar to the values of the upper continental crust(UCC).The contents of major and trace elements as well as SiO_2/Al_2O_3,K_2O/Al_2O_3,Na_2O/K_2O,Eu/Eu~*,La/Sc,Th/Sc,La/Co Th/Co,Th/Cr,Ce/Ce~* and LREE/HREE ratios,show that the analysed pelitic sedimentary rocks were formed by weathering of different types of mostly acidic(silicic),i.e.felsic rocks.  相似文献   

Discriminant function model as a tool for classification of stratigraphically undefined radiolarian cherts in ophiolite zones     

Zoran Peh  Josip Halamić 《Journal of Geochemical Exploration》2010

Two discriminant function models are constructed in order to distinguish major- and trace-element geochemical patterns characteristic for radiolarian cherts from the Zagorje–Mid-Transdanubian Zone ophiolite mélange of NW Croatia. The models are subsequently used to assign new samples from the adjacent magmatic–sedimentary complex extending from the Central Dinaridic Ophiolite Belt in NW Bosnia and thereby to test their applicability in similar cases when clear field relations are absent. In both models the first discriminant function explains the most part of the system variability. However, between the two, the trace-element model proves itself as a more helpful predictive tool presenting a straightforward example of correct classification of samples into three pre-defined groups (Triassic-basin, Triassic-slope and Jurassic radiolarian cherts). This result is extended further, with allocation of all samples from the test region into a single group (Jurassic) according to their trace-element geochemistry.  相似文献   

Behaviour of metals and nutrients in soils and groundwater of a karst polje   总被引：2，自引：0，他引：2  

Tamara Markovic  Slobodan Miko  Sanja Kapelj  Renato Buljan  Ozren Larva  Zoran Peh 《Journal of Geochemical Exploration》2006,88(1-3):124

The Croatian south part of the country is mainly composed of strongly krastified carbonate rocks. Also in this south part of Croatia is lacking of large depressions and poljes with thick covers. Some karst poljes and depressions may have thick covers, like for example the Vransko polje. The Vransko polje is characterised by an intensive agricultural activity. At the centre of the polje is located a karst spring (Turanjsko jezero), which is used for the water supply of the town Biograd and its surroundings. Total metals, nutrients (nitrate, ammonia, phosphate), organic matter content and cation exchange capacity (CEC) were measured in soil samples collected from the polje. Metals and nutrients were also measured in the water samples of channel Kotarka (which is passing through the area) and three springs (Turanjsko jezero, Kakma and Tinj). Measured total concentrations of metals of soil samples were treated by R-cluster multivariate statistical analysis. The result of statistical analysis showed grouping of metals with similar behaviour. Content of metals and nutrients were low in the spring samples but high in the water sample of the channel Kotarka, because the channel drains the water from the surroundings. Although agricultural activity in the Vransko polje is high, there is no high anthropogenic influence on groundwater and soil. They are both of good quality.  相似文献   

Hydrogeological conditions and quality of ground waters in northern Banat,Pannonian basin   总被引：1，自引：0，他引：1  

Zoran Nikic  Milka Vidovic 《Environmental Geology》2007,52(6):1075-1084

Geological relationships, hydrogeology and chemical composition of ground water in northern Banat were studied through the period 2000–2004 using the available background data from published and unpublished sources. Northern Banat is the extreme northeastern part of the Republic of Serbia and a geotectonic part of the vast Pannonian depression. The source of domestic and industrial water supply is only groundwater from artesian and subartesian aquifers of Lower Pleistocene (Q₁¹) and Upper Pleistocene (Pl₃²) sand deposits. The ground water, “peculiar” in chemical composition, is the only source of drinking water in the arid area. A notable variation in the chemical composition of artesian waters within the same geotectonic unit (Pannonian basin), abstracted for municipal water supplies of Kikinda, Novi Knezevac and Djala, has attracted attention of these authors. Our paper attempts to interpret the variation in the chemical composition of ground water and the cause of the variation by the interaction of ground water and rocks forming the aquifers on the case example of the water supply sources for the three mentioned towns. With respect to the depth and lithology of the aquifers, we interpret the varied chemical compositions of waters in the mentioned sources as a consequence of natural factors (geological environment), geological relationships and hydrogeological conditions.  相似文献   

The development and structure of the Croatian economy     

Dragutin Feletar Ph.D.  Zoran Stiperski Ph.D. 《GeoJournal》1996,38(4):437-444

The first part of the article deals with the general and historical conditions of the development of the Croatian economy, with an emphasis on industry as the dominant branch. The relatively favorable developmental possibilities of Croatia are stressed, with the combination of the agrarian Pannonian region, the forested stock-farming highland regions and the tourism-transit front of the Adriatic. The basic data on periods of historical development are mentioned, with an explanation of the five developmental stages.The second half of the article deals with a thorough analysis of the basic processes of the restructuring of the Croatian economy. Emphasis is placed on the decreased significance of agrarian and agricultural production (in 1961 Croatia had an agricultural population of 43.7%, while in 1991 it was only 9.6%), and the domination of industry, which in 1987 accounted for 35.1 percent of the employed population and 50.3 percent of the gross national product. The processes of restructuring and transition from a socialist to a market economy, as well as the wartime crisis, caused a fall in the value of industrial products to 43 percent in the years from 1990 to 1994. The branch and spatial restructuring of the economy and industry, privatization processes and the problem of increased unemployment are also analyzed.  相似文献   

A non-traditional approach to the analysis of flood hazard for dams     

Zoran Micovic  Desmond N. D. Hartford  Melvin G. Schaefer  Bruce L. Barker 《Stochastic Environmental Research and Risk Assessment (SERRA)》2016,30(2):559-581

The traditional and still prevailing approach to characterization of flood hazards to dams is the inflow design flood (IDF). The IDF, defined either deterministically or probabilistically, is necessary for sizing a dam, its discharge facilities and reservoir storage. However, within the dam safety risk informed decision framework, the IDF does not carry much relevance, no matter how accurately it is characterized. In many cases, the probability of the reservoir inflow tells us little about the probability of dam overtopping. Typically, the reservoir inflow and its associated probability of occurrence is modified by the interplay of a number of factors (reservoir storage, reservoir operating rules and various operational faults and natural disturbances) on its way to becoming the reservoir outflow and corresponding peak level—the two parameters that represent hydrologic hazard acting upon the dam. To properly manage flood risk, it is essential to change approach to flood hazard analysis for dam safety from the currently prevailing focus on reservoir inflows and instead focus on reservoir outflows and corresponding reservoir levels. To demonstrate these points, this paper presents stochastic simulation of floods on a cascade system of three dams and shows progression from exceedance probabilities of reservoir inflow to exceedance probabilities of peak reservoir level depending on initial reservoir level, storage availability, reservoir operating rules and availability of discharge facilities on demand. The results show that the dam overtopping is more likely to be caused by a combination of a smaller flood and a system component failure than by an extreme flood on its own.  相似文献   

An updated and unified earthquake catalogue for the Western Balkan Region   总被引：1，自引：0，他引：1  

Snježana Markušić  Zeynep Gülerce  Neki Kuka  Llambro Duni  Ines Ivančić  Slavica Radovanović  Branislav Glavatović  Zoran Milutinović  Sinan Akkar  Svetlana Kovačević  Jadranka Mihaljević  Radmila Šalić 《Bulletin of Earthquake Engineering》2016,14(2):321-343

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