Temperature and heat flux changes at the base of Laurentide ice sheet inferred from geothermal data (evidence from province of Alberta,Canada)     

Demezhko  Dmitry  Gornostaeva  Anastasia  Majorowicz  Jacek  Šafanda  Jan 《International Journal of Earth Sciences》2018,107(1):113-121

International Journal of Earth Sciences - Using a previously published temperature log of the 2363-m-deep borehole Hunt well (Alberta, Canada) and the results of its previous interpretation, the...  相似文献   

Origin and evolution of the Bezedna lake–mire complex in the Lublin area (East Poland): a case study for permafrost lakes in karstic regions     

Radosław Dobrowolski  Piotr Kulesza  Jacek Łojek  Irena Agnieszka Pidek 《Journal of Paleolimnology》2015,53(2):191-213

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In situ LA-ICP-MS investigation of the geochemistry and U-Pb age of rutile from the rocks of the Belomorian mobile belt   总被引：1，自引：0，他引：1  

S. G. Skublov  T. Zack  A. V. Berezin  A. E. Mel’nik  N. G. Rizvanova 《Geochemistry International》2013,51(2):164-171

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Planning the Colca Canyon and the Valley of the Volcanoes National Park in South Peru   总被引：1，自引：1，他引：0  

Andrzej Paulo  Andrzej Gałaś  Slávka Gałaś 《Environmental Earth Sciences》2014,71(3):1021-1032

The economic development of the Rio Colca region and related infrastructure endangers the environment of the deepest canyon worldwide. The unique values of the Colca Valley and Canyon and its tributary Valley of the Volcanoes are summarised. They include a magnificent, deep section of the orogenic belt 100 km long, different geological formations, active faults, a variety of fold structures, young volcanoes, hot springs, geysers, several ecological zones and the largest condor habitat in the Andes. Based on the observed land use, development and regional planning, the threats and conflict areas are outlined. Studies performed by the Polish Scientific Expedition to Peru since 2003 add greatly to the knowledge of geology, landscape and pioneering biota development of the area and its importance to the world heritage of nature. They are aimed to give scientific background to the project of the Canyon Colca and Valley of the Volcanoes National Park. The article gives the proposed limits of the park and its buffer zones, categories of protection zones compatible with the SINANPE system of Peru and suggestions on tourist accessibility. The strict protection zone should cover the most inaccessible part of the area where human economic activity practically does not exist. Traditional farming and animal husbandry, wildlife, cultural tourism and some forms of adventure tourism will be allowed in the zone of special usage. The new park would strengthen the relatively poor system of the protected areas in the Arequipa Department, increase tourist attractiveness and determine constraints for sustained regional development. The expected actions of the park authority and local governments are specified.  相似文献   

Longitudinal asymmetry of craters' density distributions on the icy satellites     

Jacek Leliwa-Kopystynski  Marcin Banaszek  Ireneusz Wlodarczyk 《Planetary and Space Science》2012,60(1):181-192

Crater's density distribution versus satellitographical longitude was searched for seven icy satellites: two of Jupiter (Ganymede and Callisto) and five of Saturn (Mimas, Tethys, Dione, Rhea and Iapetus). Craters were classified according to their size. Four bins of the craters' diameter were used. Density distributions were found in the longitudinal sectors of the near-equatorial stripes that circumscribe the satellites. The size distributions (R-plots) were done independently for each of the eight longitudinal sectors of the satellites. Searching for the leading/trailing (apex/antapex) and the near-side/far-side asymmetry was done. It was found that the crater density is longitudinally asymmetric for all seven satellites being studied. However, the apex–antapex asymmetry is much less pronounced than predicted by theory of Zahnle et al. (2003), for impacts on the satellites by ecliptic comets. We conclude that the impact craters observed on the considered satellites are mostly originated from planetocentric swarm of debris. In that case longitudinal asymmetry is not expected, as stated by Horedt and Neukum, 1984a, Horedt and Neukum, 1984b. However, cratering longitudinal asymmetry that we observe for Mimas perfectly agrees with calculations of Alvarellos et al. (2005). It is very likely that important part of craters on Mimas were formed due to impacts of ejecta originated from crater Herschel.  相似文献   

GIS‐based multicriteria decision analysis: a survey of the literature     

Jacek Malczewski 《International journal of geographical information science》2013,27(7):703-726

The integration of GIS and multicriteria decision analysis has attracted significant interest over the last 15 years or so. This paper surveys the GIS‐based multicriteria decision analysis (GIS‐MCDA) approaches using a literature review and classification of articles from 1990 to 2004. An electronic search indicated that over 300 articles appeared in refereed journals. The paper provides taxonomy of those articles and identifies trends and developments in GIS‐MCDA.  相似文献   

Geosocial gauge: a system prototype for knowledge discovery from social media     

Arie Croitoru  Andrew Crooks  Jacek Radzikowski  Anthony Stefanidis 《International journal of geographical information science》2013,27(12):2483-2508

The remarkable success of online social media sites marks a shift in the way people connect and share information. Much of this information now contains some form of geographical content because of the proliferation of location-aware devices, thus fostering the emergence of geosocial media – a new type of user-generated geospatial information. Through geosocial media we are able, for the first time, to observe human activities in scales and resolutions that were so far unavailable. Furthermore, the wide spectrum of social media data and service types provides a multitude of perspectives on real-world activities and happenings, thus opening new frontiers in geosocial knowledge discovery. However, gleaning knowledge from geosocial media is a challenging task, as they tend to be unstructured and thematically diverse. To address these challenges, this article presents a system prototype for harvesting, processing, modeling, and integrating heterogeneous social media feeds towards the generation of geosocial knowledge. Our article addresses primarily two key components of this system prototype: a novel data model for heterogeneous social media feeds and a corresponding general system architecture. We present these key components and demonstrate their implementation in our system prototype, GeoSocial Gauge.  相似文献   

Assessment of greenhouse gas emissions from agricultural sources in order to plan for needs of low carbon economy at local level in Poland     

Paweł Wiśniewski  Mariusz Kistowski 《Geografisk tidskrift / udgivet af Bestyrelsen for Det Kongelige danske geografiske selskab》2013,113(2):123-136

Agriculture is often not included in the baseline greenhouse gas (GHG) emission inventories created for local low carbon economy plans in Poland and other European countries. We therefore estimate the size of the carbon footprint from agricultural sources and indicate the share of agriculture in the total GHG emissions in selected Polish communes (LAU level 2). We propose a solution whereby local government units can estimate their carbon footprint independently and monitor the impact of actions taken to reduce emissions. The value of the carbon footprint from agriculture in the selected communes varies from .5 to 46.5 thousand Mg CO₂eq/year, with a mean value of 12.6 thousand Mg CO₂eq/year and a standard deviation of 11.4 thousand Mg CO₂eq/year. Per capita, these values range from 10 kg CO₂eq/year to 8.4 Mg CO₂eq/year, with a mean of 1.1 Mg CO₂eq/year and a standard deviation of 1.5 Mg CO₂eq/year. In all communes, the contribution of agriculture to total emissions is at an average of 14% (values range from .2 to 57.4%). The obtained results confirm the appropriateness of including emissions from the agricultural sector and other related sources in low carbon economy plans.  相似文献   

Harvesting ambient geospatial information from social media feeds   总被引：5，自引：0，他引：5  

Anthony Stefanidis  Andrew Crooks  Jacek Radzikowski 《GeoJournal》2013,78(2):319-338

Social media generated from many individuals is playing a greater role in our daily lives and provides a unique opportunity to gain valuable insight on information flow and social networking within a society. Through data collection and analysis of its content, it supports a greater mapping and understanding of the evolving human landscape. The information disseminated through such media represents a deviation from volunteered geography, in the sense that it is not geographic information per se. Nevertheless, the message often has geographic footprints, for example, in the form of locations from where the tweets originate, or references in their content to geographic entities. We argue that such data conveys ambient geospatial information, capturing for example, people’s references to locations that represent momentary social hotspots. In this paper we address a framework to harvest such ambient geospatial information, and resulting hybrid capabilities to analyze it to support situational awareness as it relates to human activities. We argue that this emergence of ambient geospatial analysis represents a second step in the evolution of geospatial data availability, following on the heels of volunteered geographical information.  相似文献   

Marine ferromanganese concretions from the polish exclusive economic zone: Influence of major inflows of north sea water     

G. P. Glasby  Sz. Uścinowicz  J. A. Sochan 《Marine Georesources & Geotechnology》2013,31(4):335-352

Ferromanganese concretions within the Polish Exclusive Economic Zone (EEZ) are found mainly in the depth range 60–70 m on the thresholds between the Bomholm Basin and Slupsk Furrow and between the Gotland and Gdansk Basins. They also occur on elevations of the seafloor within the Bomholm Basin, on the southern slopes of Slupsk Furrow, and on the lower southwestern slopes of the Gotland Basin. They occur mainly as surface deposits on very thin (<0.2 m), poorly sorted lag deposits. The concretions are predominantly discoidal and are formed around a single nucleus of sandstone or erratic rock of variable size. The ferromanganese oxides display internal layering with alternate layers of almost black manganese oxides and buff iron axyhydroxides. The concretions consist mainly of todorokite and quartz, with lesser amounts of feldspar, kaolinite, and montmorillonite. They are characterized by relatively high Fe/Mn ratios (0.9–3.5) and high contents of detrital elements (Ti, Na, K, Ca, and Mg) but low contents of the transition elements (Cu, Zn, Pb, Cr, Co, and Ni). The deposits are associated with the very dynamic environment near the halocline, where internal waves erode the sediment and create conditions of sediment nondeposition favorable for the formation of the concretions. A number of factors contribute to the high abundance of ferromanganese concretions in the Baltic Sea. One is the high input of iron and manganese by the rivers draining into it This is a consequence of the widespread occurrence of bogs and swamps in the catchment area of the Baltic Sea, which results in the river waters having high humic acid contents and low pH. Another major factor is the buildup of dissolved iron and manganese in the anoxic basins of the Baltic Sea during periods of stagnation. These waters are flushed during major inflow events, when oxygenated water from the North Sea displaces the stagnant waters of the anoxic basins. Iron and manganese in these waters are then transported laterally and deposited in the surface of ferromanganese concretions on topographic highs. We believe that the iron is deposited rapidly after such events but that the manganese is deposited over a much longer time period, thus accounting for the layering in the concretions. The rate of deposition of these elements is essentially controlled by the input of oxygen in the waters of the North Sea. These periods of major inflows are grouped but significant events, for concretions occur on average about 11 times per century. We therefore estimate that the concretions have grown much more slowly than previously thought (about 0.013–0.018 mm/yr), and that a concretion 20 mm in diameter would have an age of about 500–800 years. Higher concentrations of heavy metals have been recorded in the outer layers of the concretions, and it is possible that these can serve as indicators of heavy‐metal pollution in the Baltic Sea. The concretions range from sporadic to intermediate abundance. As such, they have no economic potential.  相似文献