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131.
In this paper we present magnitude (Ms) – magnitude(mb) and magnitude-intensity relationships which areconsidered the most adequate in the Ibero-Maghrebianregion. This work is based on selected samples ofrecently revised events with magnitude mb assigned bythe Instituto Geográfico Nacional (I.G.N.) and Msassigned by I.S.C and N.E.I.C., and isoseismal mapsfrom 142 events. Using these data, we have obtainedone magnitude (Ms) – magnitude (mb) relationship, twomagnitude (mb and Ms) assignment relationships viaepicentral intensity (I0), and ten magnitude (mb andMs) assignments relationships via macroseismicinformation: four using Ambraseys' methodology (1985)and six using the isoseismal area of degree III, IV and VI.According to the obtained results it could be concluded that historical magnitude assignment with lesser uncertainties are those obtained via macroseismic information using magnitude-intensity relationships with Ambraseys' methodology (1985). The magnitude-isoseismal area assignment relationships have, in most cases, great differences depending on the degree of the isoseismal area used. Magnitude assignments via epicentral intensity have the highest uncertainties. Geographic regionalization of the relationshipshas been studied but the highest correlations and statistical significance are obtained when we fit all the Ibero-Maghrebian region data.Finally we have used the results obtained in this workto assign magnitude to some important historicalearthquakes in the Ibero-Maghrebian region: the 1755Lisbon earthquake, the 1680 Málaga earthquake, the1829 Torrevieja earthquake and the 1884 Arenas del Reyearthquake. According to our relationships andmethodology we have assigned an Ms value of 9.3 ±0.6 to the 1755 Lisbon earthquake (its mb magnitudecannot be estimated due to the saturation of the mbscale), an mb value of 6.3 ±0.4 and an Ms valueof 6.9 ± 0.6 to the 1829 Torrevieja earthquake, anmb value of 6.2 ± 0.4 and an Ms value of 6.4 ±0.6 to the 1680 Málaga earthquake and an mb valueof 6.1 ± 0.4 and an Ms value of 6.5 ± 0.6 tothe 1884 Arenas del Rey earthquake. 相似文献
132.
战区军事地理系列专题地图制图研究 总被引:1,自引:0,他引:1
本文论述了制作战区军事地理系列专题图的必要性和可能性:以济南战区为例,以军事地理学和地图制图学为基础理论,探讨了战区军事地理系列专题地图的图幅构成与设计的基本原理和方法;并在微机上初步研制了制作该系列专题地图的软件系统。 相似文献
133.
陈毓芬 《测绘科学技术学报》2000,17(1):53-56
在地图的色彩设计中,设计人员不仅要考虑色彩单独使用的效果,而且要考虑地图上各要素的色彩配合,即各种色彩在图面上的整体感受效果。电子地图由于有极大的色彩选择空间,背景色也不局限于白色,因而选色、配色比纸质地图更加复杂。用哪种颜色作为背景色视觉效果较好?图面上各要素的色彩如何配合?针对这两个问题,作者设计了电子地图的一个色彩感受实验——色彩配合实验,利用自编的电子地图视觉感受测试软件(TEVP)进行了实验,文中介绍了该实验的方法和思路。 相似文献
134.
135.
Hydrogeochemical investigations and groundwater provinces of the Friuli Venezia Giulia Plain aquifers,northeastern Italy 总被引:2,自引:0,他引:2
Water resources are a key factor, particularly for the planning of the sustainable regional development of agriculture, as
well as for socio-economic development in general. A hydrochemical investigation was conducted in the Friuli Venezia Giulia
aquifer systems to identify groundwater evolution, recharge and extent of pollution. Temperature, pH, electric conductivity,
total dissolved solids, alkalinity, total hardness, SAR, Ca2+, Na+, K+, Mg2+, Cl−, SO4
2−, NO3
−, HCO3
−
, water quality and type, saturation indexes and the environmental stable isotope δ18O were determined in 149 sampling stations. The pattern of geochemical and oxygen stable isotope variations suggests that
the sub-surface groundwater (from phreatic and shallow confined aquifers) is being recharged by modern precipitations and
local river infiltrations. Four hydrogeological provinces have been recognised and mapped in the Friuli Venezia Giulia Plain
having similar geochemical signatures. These provinces have different degrees of vulnerability to contamination. The deep
confined groundwater samples are significantly less impacted by surface activities; and it appears that these important water
resources have very low recharge rates and would, therefore, be severely impacted by overabstraction. 相似文献
136.
《The Professional geographer》1988,40(1):116-131
Books reviewed in this article: Boundary Control and Legal Priniciples . Curtis M. Brown , Walter G. Robillard and Donald A. Wilson . Lost Initiatives: Canada's Forest Industries, Forest Policy, and Forest Conservation . R. Peter Gillis and Thomas R. Roach . The Navajo Atlas: Resources, People, and History of the Dine Bikeyah . James M. Goodman . The City and the Sign . M. Gottdiener AND Alexandros Ph . Lagopoulos , EDS. The Comfortable House: North American Suburban Architecture 1890–1930 . Alan Gowans . Arabic-Islamic Cities. Building and Planning Principles . Besim Salim Hakim . Contemporary Climatology . Ann Henderson -Sellers and Peter J. Robinson . A Trace of Desert Waters . Samuel G. Houghton . Geography, Resources and Environment. Vol. 1: Selected Writings of Gilbert F. White. Vol. 2: Themes from the Work of Gilbert F. White . Robert W. Kates AND Ian Burton , ED. Spatial Dimensions of Unemployment and Underemployment (A Case Study of Rural Punjab) . Gopal Krishan . Maps of the Holy Land: Cartobibliography of Printed Maps, 1475–1900 . Compiled by Eran Laor , assisted by Shoshana Klein . The Geography of Third World Cities . Stella Lowder . A Perspective on U.S. Farm Problems and Agricultural Policy . Lance Mc Kinzie , Timothy G. Baker AND Wallace E. Tyner . Soil Erosion and Its Control. R.P.C . Morgan , ED Geopolitics . Patrick O'Sullivan . Landscape, Meanings and Values . Edmund C. Penning -Rowsell AND David Lowenthal , EDS. 相似文献
137.
《International Journal of Digital Earth》2013,6(5):421-433
Abstract Sources of heterogeneous geospatial data such as the elevation, the slope, the aspect, the water network and the current settlements related to the known Neolithic archaeological sites of Magnesia, are used in an attempt to confirm the existence and allow for the prediction of other archaeological sites using predictive modelling theory. Predictive modelling allows the update of the problem solving strategy as soon as new data layers are available. The Dempster–Shafer Theory also commonly referred to as evidential reasoning (ER) is used to compose probability maps of areas of archaeological interest from physiographical and historical data. The advantage of this theory is that the ignorance is quantified and used to compose the probability maps named as belief, plausibility and belief interval for the archaeological sites. The final digital probability maps show that the Neolithic archaeological sites can be detected in the prefecture of Magnesia. This research study forms a methodological tool for the prediction of new archaeological sites in other areas of archaeological interest according to the physiographical and historical characteristics of the archaeological period being examined. It also contributes to the digital earth modelling and archaeological site protection, one of the most critical and challenging global initiatives. 相似文献
138.
Thematic maps can be analyzed by multiple regression for (1) forward prediction where a younger geological structural map is written as a least-squares function of older maps for information on historical perspectives or (2) by backward prediction where an older map is regressed stepwise on a series of younger ones to aid in prospecting. The technique was evaluated by a series of structure maps on different geological horizons from the U.S. Midcontinent (Kansas) where the forward prediction proved more effective than backward. In forward prediction, the first map entered into a multiple regression is invariably the immediately underlying one as expected. On the other hand, the first map in a backward prediction is not necessarily related to stratigraphy which limits the utility of the technique for prospecting. 相似文献
139.
《Geodinamica Acta》2013,26(6):431-446
Paleoenvironmental reconstructions and climatic modelling allow us to investigate the influence of water and sediment supply on the preservation of fluvial systems within a given geodynamic context. To simulate climate, we need global-scale paleoenvironmental and paleotopographic reconstructions. However, the present study only covers the West-Tethys domain, where sedimentological and stratigraphic data allow us to check climate simulation results against geological data. We focus our modelling on the Olenekian, with the aim of characterizing the impact of climate on fluvial sedimentation in the West-Tethys domain. The climatic simulations show that paleoclimates differ between Western Europe and North Africa. A more humid climate is simulated over North Africa, whereas a rather arid climate prevails over Western Europe. In Western Europe, the sediments are preserved for the most part in endoreic basins and the presence of rivers in an arid environment suggests that these rivers are mainly fed by precipitation falling on the North Africa Variscan Mountains. In North Africa, sedimentation is exclusively preserved in exoreic basins (coastal plain sediments). Consequently, the lack of preserved fluvial systems in endoreic basins in North Africa either could be due to a shortage of accommodation space in this area, or is linked to the climatic conditions that controlled the water and sediment supply. 相似文献
140.
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