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981.
Sudhir Kumar Singh Prosper Basommi Laari Sk. Mustak Prashant K. Srivastava Szilárd Szabó 《国际地球制图》2013,28(11):1202-1222
AbstractAn integrated Markov Chain and Cellular Automata modelling (CA MARKOV), multicriteria evaluation techniques have been applied to produce transition probability. The unsupervised method was employed to classify the satellite images of year 1985, 1995, 2005 and 2015 to meet the magnitude of LULC change. Results showing the spatial pattern of the sub-basin is largely influenced by the biophysical and socio-economic drivers leading to growth of agricultural lands and built-up area in the basin. Simulated plausible future LULC changes for 2025 which is based on a CA MARKOV that integrates Markovian transition probabilities computed from satellite-derived LULC maps and a CA contiguity spatial filter (5 × 5). Further, the fragmentation analysis was performed to check the fragmentation scenario in the year 2025. The result for year 2025 with reasonably good accuracy will be useful to the planners, policy- and decision-makers. 相似文献
982.
Two studies using LANDSAT imagery are summarized. The urban area study of the city of Budapest uses a statistical classifying method with ground truth to identify eleven land use categories resulting in a 60 to 80% reliability. The rural area study of Komarom County attempts to use LANDSAT to monitor the utilization of farms of agri-ecological research by identifying actual cropland patterns. Translated by the authors and submitted for publication in June, 1984. 相似文献
983.
William Caballero Ramón Giraldo Jorge Mateu 《Stochastic Environmental Research and Risk Assessment (SERRA)》2013,27(7):1553-1563
In a wide range of scientific fields the outputs coming from certain measurements often come in form of curves. In this paper we give a solution to the problem of spatial prediction of non-stationary functional data. We propose a new predictor by extending the classical universal kriging predictor for univariate data to the context of functional data. Using an approach similar to that used in univariate geostatistics we obtain a matrix system for estimating the weights of each functional variable on the prediction. The proposed methodology is validated by analyzing a real dataset corresponding to temperature curves obtained in several weather stations of Canada. 相似文献
984.
Tamás Vigh Tibor Kovács János Somlai Norbert Kávási Márta Polgári Lóránt Bíró 《Acta Geophysica》2013,61(4):831-847
Previously, little attention has been paid to terrestrial radioisotopes (U, Th, 40K) occurring in manganese ores, despite the fact that the biogeochemical relationship between Mn and U is versatile. Occurrence of terrestrial radioisotopes in great amounts during mining on a long-term causes significant radiation exposure. It is important to inspect black shale-hosted manganese ores from this aspect, as black shales are typically potential U-rich formations. Despite the increased radon concentration in the mine, based on the detailed major elements, trace elements and gamma spectroscopy inspection of the rock types of deposit, the U, Th enrichment was undetectable. However, the U and Th content of about average terrestrial abundance of the great ore amount may be in the background of the increased radon concentration level. This Mn-carbonate ore deposit in spite of the low U content exhibit potential radon danger for miners, which can be eliminated with intensive air change only. 相似文献
985.
Ákos Gyulai Mihály Dobróka Tamás Ormos Endre Turai Tibor Sasvári 《Acta Geophysica》2013,61(5):1184-1195
The methods of in-mine seam-sounding and transillumination (geoelectric tomography) for the detection of tectonic disturbances of coal seams were developed by the Department of Geophysics of the University of Miskolc in the 1970–80’s with the effective support of the former “Borsod” Coal Mines Ltd. The paper gives an overview about the theory of seam-sounding and a special geoelectric tomographic inversion, and introduces the in-mine geoelectric seam-sounding and transillumination measurement systems using vertical electrode dipoles. In the second part the paper, the results of an in-mine geoelectric measurement are presented, which was carried out in order to detect tectonic disturbances of the Miocene aged coal seams situated in Slovakia. As results of the geophysical investigation, the authors forecasted the tectonic features in the coal seam. The company confirmed the results by independent information about seam disturbances and tectonic features arising from the excavation of the investigated area. 相似文献
986.
Javier Santos-González João A. Santos Rosa Blanca González-Gutiérrez José María Redondo-Vega Amelia Gómez-Villar 《自然地理学》2013,34(6):471-490
Fabric and grain-size analysis of eight deposits present in the Upper Sil River Basin palaeoglacial system of northwest Spain were used to interpret till types and to reconstruct the glacial paleoprocess history of this region. They are represented by lodgement, deformation, and melt-out tills. The first, representative of glacial advance stages, present cluster fabrics and are generally composed of poorly sorted and finer sediments. Melt-out and deformation tills, representative of stages of glacial stability followed by fast recession, present transitional to girdle fabrics and are composed of poorly sorted coarser sediments. In any case, multiple criteria, including lithological, clast-shape, or structural data, support these directional and grain-size observations. These sequences, most of them located in the snout area of the Sil palaeoglacier, are important in the reconstruction of glacial dynamics due to poor preservation of landforms related to the maximum glacial advance. This palaeoglacial system was formed by multiple tributaries and had an extension of over 450 km2, with the Sil paleoglacier being 51 km long during its maximum glacial advance. 相似文献
987.
Ryszard Kornijów 《Journal of Paleolimnology》2013,49(2):301-304
The new sediment slicer described herein provides an easy and time-efficient way of sectioning cores of varying length, diameter, and composition from a wide range of habitats and sediment types. It is designed to process sediments collected by means of any soft-sediment core sampler with the core tube detachable from the sampler head and trigger unit. It is useful for sectioning core samples that include both the undisturbed sediment/water interface and highly consolidated sediments. The slicer is composed of three parts: (1) a supporting block, (2) a gliding block with the incorporated 10 cm sub-sampler holder designed to glide freely in the grooves along the supporting block, and (3) a metal blade for sediment slicing. 相似文献
988.
Antonio Tomás Mozas-Calvache Francisco Javier Ariza-López 《International journal of geographical information science》2013,27(11):2170-2187
ABSTRACTThe sharing of Global Navigation Satellite System (GNSS) tracks on the Internet is increasing enormously. Every day a great number of users capture routes using different devices and share these data. Individually these tracks present a poor positional accuracy because these devices obtain positions with accuracy of about 5-10 metres. In addition, they are usually captured for navigation and not for surveying. However, we can take advantage of the great quantity of tracks of the same linear element in order to obtain a more accurate solution. This study analyses this possibility using a wide set of tracks obtained in known conditions. We emulated those tracks obtained by Volunteered Geographic Information (VGI) users and we compared the mean axis obtained using all tracks with others obtained from a more accurate source. Additionally, we analyse the displacement of other axes obtained by varying several parameters such as the number of tracks and their length or by dividing the route into sections in function of sinuosity, etc. The results have shown an improved 3D mean axis and the viability of the method proposed in this study in order to use axes obtained from several tracks in maps at certain scales. 相似文献
989.
This study explores the surface variability of alluvial fans from digital elevations model (DEM) derivatives generated from 1-m planimetric resolution airborne laser swath mapping data. Channel and interfluve dimensions of debris flow (DF) fans and fans generated from predominantly fluvial flows and some older debris flows (mixed flow [MF]) are extracted with the aid of a planimetric curvature classification. Significant differences are identified between the fan surface topography of DF and MF fans. MF fans tend to have smaller channel and interfluve widths, have smaller elevation differences between the crest of the interfluve and channel, and are more dissected than DF fans. The morphometric differences between the two fan classes can be explained by differences in the primary processes that develop the surficial features, but also the preponderance for secondary erosional processes acting on the MF fans. 相似文献
990.
Imprints of hydrocarbon-bearing basinal fluids on a karst system: mineralogical and fluid inclusion studies from the Buda Hills,Hungary 总被引:1,自引:1,他引:0
Zsófia?PorosEmail author Andrea?Mindszenty Ferenc?Molnár Jacques?Pironon Orsolya?Gy?ri Paola?Ronchi Zoltán?Szekeres 《International Journal of Earth Sciences》2012,101(2):429-452
Calcite veins and related sulphate–sulphide mineralisation are common in the Buda Hills. Also, abundant hypogenic caves are
found along fractures filled with these minerals pointing to the fact that young cave-forming fluids migrated along the same
fractures as the older mineralising fluids did. The studied vein-filling paragenesis consists of calcite, barite, fluorite
and sulphides. The strike of fractures is consistent—NNW–SSE—concluding a latest Early Miocene maximum age for the formation
of fracture-filling minerals. Calcite crystals contain coeval primary, hydrocarbon-bearing- and aqueous inclusions indicating
that also hydrocarbons have migrated together with the mineralising fluids. Hydrocarbon inclusions are described here for
the first time from the Buda Hills. Mixed inclusions, i.e., petroleum with ‘water-tail’, were also detected, indicating that
transcrystalline water migration took place. The coexistence of aqueous and petroleum inclusions permitted to establish the
entrapment temperature (80°C) and pressure (85 bar) of the fluid and thus also the thickness of sediments, having been eroded
since latest Early Miocene times, was calculated (800 m). Low salinity of the fluids (<1.7 NaCl eq. wt%) implies that hydrocarbon-bearing
fluids were diluted by regional karst water. FT-IR investigations revealed that CO2 and CH4 are associated with hydrocarbons. Groundwater also contains small amounts of HC and related gases on the basin side even
today. Based on the location of the paleo- and recent hydrocarbon indications, identical migration pathways were reconstructed
for both systems. Hydrocarbon-bearing fluids are supposed to have migrated north-westward from the basin east to the Buda
Hills from the Miocene on. 相似文献