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131.
JON Y. LANDVIK ASTRID LYSÅ SVEND FUNDER MICHAEL KELLY 《Boreas: An International Journal of Quaternary Research》1994,23(4):412-423
Coastal Jameson Land is characterized by thick Quaternary deposits from the last interglacial/glacial cycle. The successions at the mouth of Langelandselv exhibit a key stratigraphy where sediments from the Langelandselv interglaciation (Eemian) are overlain by three till units interbedded with glacimarine and deltaic interstadial successions. Immediately after the retreat of glaciers after the extensive Scoresby Sund glaciation (Saalian). advection of warm Atlantic surface water surpassed what is known from the Holocene. The two lowermost Weichselian tills, deposited during the Aucellaelv and Jyllandselv stades (Early Weichselian), reflect short-lasting readvances of fjord glaciers. Luminescence dates and correlation with adjacent areas suggest ages of 110–80 ka and 70–60 ka for the Hugin Sø and the Møselv interstades, respectively. 相似文献
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133.
In the Boi Massif of Western Timor the Mutis Complex, which is equivalent to the Lolotoi Complex of East Timor, is composed of two lithostratigraphical components: various basement schists and gneisses; and the dismembered remnants of an ophiolite. Cordierite-bearing pelitic schists and gneisses carry an early mineral assemblage of biotite + garnet + plagioclase + Al-silicate, but contain no prograde muscovite; sillimanite occurs in a textural mode which suggests that it replaced and pseudomorphed kyanite at an early stage and some specimens of pelitic schist contain tiny kyanite relics in plagioclase. Textural relations between, and mineral chemistries of, ferro-magnesian phases in these pelitic chists and gneisses suggest that two discontinuous reactions and additional continuous compositional changes have been overstepped, possibly with concomitant anatexis, as a result of decrease in Pload during high temperature metamorphism. The simplified reactions are: garnet and/or biotite + sillimanite + quartz + cordierite + hercynite + ilmenite + excess components. P-T conditions during the development of the early mineral assemblage in the pelitic gneisses are estimated to have been P + 10 kbar and T > 750°C, based upon the plagioclase-garnet-Al-silicate-quartz geobarometer and the garnet-biotite geothermometer. P-T conditions during the subsequent development of cordierite-bearing mineral assemblages in the pelitic gneisses are estimated to have been P + 5 kbar and T + 700°C with XH2O < 0.5, based upon the Fe content of cordierite occurring in the assemblage quartz + plagioclase + sillimanite + biotite + garnet + cordierite coexisting with melt. Final equilibration between some of the phases suggests that conditions dropped to P > 2.3 kbar and T > 600°C. A similar exhumation P-T path is suggested for the pelitic schists with early metamorphic conditions of P > 6.2 kbar and T > 745°C and subsequent development of cordierite under conditions in the range P = 3-4 kbar and T = 600-700°C. The tectonic implications of these P-T estimates are discussed and it is concluded that the P-T path followed by these rocks was caused by decompression during rifting and synmetamorphic ophiolite emplacement resulting from processes during the initiation and development of a convergent plate junction located in Southeast Asia during late Jurassic to Cretaceous time. 相似文献
134.
MICHAEL ROCHE 《New Zealand geographer》2002,58(1):23-32
Historians and geographers have variously explored the WWI discharged soldier settlement schemes in New Zealand. The shared orthodoxy has emphasised the widespread failure of many of these soldier settlers and settlements. Recently there have been signs of a revisionist interpretation of the scheme. This paper extends this critique by considering the meanings of failure and success in broader terms through two New Zealand case studies. The discussion suggests that there were subtle graduations of both administrative and settler success and failure. 相似文献
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137.
Tidal variations in the Sundarbans Estuarine System, India 总被引:1,自引:0,他引:1
MEENAKSHI CHATTERJEE D SHANKAR G K SEN P SANYAL D SUNDAR G S MICHAEL ABHISEK CHATTERJEE P AMOL DEBABRATA MUKHERJEE K SUPRIT A MUKHERJEE V VIJITH SIDDHARTHA CHATTERJEE ANWESHA BASU MADHUMITA DAS SARANYA CHAKRABORTI ARAVIND KALLA SURJA KANTA MISRA SOUMYA MUKHOPADHYAY GOPAL MANDAL KANKAN SARKAR 《Journal of Earth System Science》2013,122(4):899-933
138.
Abstract Based on the water balance model LARSIM (Large Area Simulation Model), a model for the simulation of nitrogen transport was developed in a mesoscale catchment in southwest Germany. To meet the needs and constraints in river basin management, the nitrogen model was developed following the concept of minimum information requirement (MIR). The modelling concept uses only few calibration parameters and only easily accessible input data. Water balance, runoff generation and nitrogen transport were simulated on a 1-km2 grid of sub-areas in which different land-use classes and soil characteristics were accounted. Temporal variability of the storage of mobile nitrogen were described using a monthly based mass balance. Nitrogen mobilization and transport was simulated using monthly values of different runoff components and data for soil properties, topography, hydrogeology and river network. The simulation was calibrated and validated using streamflow from two gauging stations and observed nitrogen concentrations at the catchment outlet, showing reasonable results for both streamflow and nitrogen dynamics. The results of the model application are discussed in the context of uncertainty problems and their implications for water management. 相似文献
139.
Abstract The incorporation of the technology of geographic information systems (GIS) into a wide range of planning decisions makes it important that the visually handicapped have access to GIS-based map products to participate more fully in community decision making. Fortunately, GIS contain many procedures useful to the design of tactile maps, including changes of scale and simplification. Developing research opportunities are outlined within the context of the general problem. Tactile maps using microcapsule paper can be produced quickly, but they must be tested using visually handicapped subjects to ensure that suitable symbolization and specifications are developed. 相似文献
140.
MICHAEL F. GOODCHILD SUN GUOQING YANG SHIREN 《International journal of geographical information science》2013,27(2):87-103
Abstract An error model for spatial databases is defined here as a stochastic process capable of generating a population of distorted versions of the same pattern of geographical variation. The differences between members of the population represent the uncertainties present in raw or interpreted data, or introduced during processing. Defined in this way, an error model can provide estimates of the uncertainty associated with the products of processing in geographical information systems. A new error model is defined in this paper for categorical data. Its application to soil and land cover maps is discussed in two examples: the measurement of area and the measurement of overlay. Specific details of implementation and use are reviewed. The model provides a powerful basis for visualizing error in area class maps, and for measuring the effects of its propagation through processes of geographical information systems. 相似文献