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51.
The paper presents an overview of the Upper Adriatic as a contact area between different cultural, social, economic and political entities, producing potential conflicts in the last century. The first part of the 20th century represented a classic example of geopolitical conflict through two World Wars and their related Peace Conferences that deeply impacted the region. Conflicts arising from the mid-century solution of the Trieste question transformed the Upper Adriatic into a laboratory of contemporary political geographic transformation. Changing geopolitical patterns have also modified the political, social and ethnic construction of the Upper Adriatic. The process of creating new international boundaries in the region ended in 1991 with the independence of Slovenia and Croatia. Through these geopolitical transformations in the Upper Adriatic, new political geographic attitudes evolved. Early on, Ratzel's geopolitical principles of defining borders as power barometers between neighbors dominated. More recently, attitudes have reflected modern integrative ideas with a focus on looking for harmony and the elimination of international conflicts. Greater attention has thus been given to the political geography of `everyday life', inter-ethnic relations, and cross-border contacts. Hence, `new' borderlands of the Upper Adriatic are more receptive to integration because they seek to overcome conflicts caused by the division of traditionally homogeneous spaces as local level political and ideological hindrances disappear. The region divided among Italy, Slovenia, and Croatia is becoming a new and special type of European borderland in the new century. 相似文献
52.
Čermák Vladimír Šafanda Jan Krešl Milan Dědeček Petr Bodri Louise 《Studia Geophysica et Geodaetica》2000,44(3):430-441
Long-term (1961 – 1996) meteorological air temperature series together with the reconstructed ground surface temperature histories, obtained by inverting borehole temperature-depth profiles, were used to project regional patterns of the recent (climate) warming rate on the territory of the Czech Republic. The characteristic magnitude of the warming rate of 0.02 –0.03 K/yr was confirmed by the results of several years of monitoring the temperature in two experimental boreholes. The monitoring of shallow temperatures at depths of about 30 –40 m, i.e. below the reach of the seasonal surface temperature variations, can serve as an alternative tool of direct quantitative assessment of the present warming rate. The data also seem to sustain a potential man-made component contributing to the more pronounced recent warming rate observed in the areas of large agglomeration. 相似文献
53.
Poleward-moving auroral forms, as observed by meridian-scanning photometers, in the vicinity of the cusp region are generally assumed to be the optical signature of flux transfer events. Another class of quasi-continuous, short period (1–2 min) wave-like auroral emission has been identified, closely co-located with the convection reversal boundary in the post-noon sector, which is similar in appearance to such cusp aurora. It is suggested that these short period wave-like auroral emissions, the optical signature of boundary plasma sheet precipitation in the region 1 field-aligned current system, are associated with ULF magnetohydrodynamic wave activity, which is observed simultaneously by ground magnetometer stations. This association with ULF wave activity is strengthened by the observation of several harmonic frequencies in the pulsation spectrum, each an overtone of the fundamental standing wave resonance frequency. 相似文献
54.
Rapid cooling and geospeedometry of granitic rocks exhumation within a volcanic arc: A case study from the Central Slovakian Neovolcanic Field (Western Carpathians) 下载免费PDF全文
U–Pb Sensitive High‐Resolution Ion MicroProbe (SHRIMP) dating of zircon in combination with (U–Th)/He dating of zircon and apatite is applied to constrain the emplacement and exhumation history of the youngest granitic rocks in the Western Carpathians collected in the Central Slovakian Neovolcanic Field. Two samples of diorite from the locality Banky, and granodiorite from Banská Hodru?a yield the U–Pb zircon concordia ages of 15.21 ±0.19 Ma and 12.92 ±0.27 Ma, respectively, recording the time of zircon crystallization and the intrusions’ emplacement. Zircon (U–Th)/He ages of 14.70 ±0.94 (Banky) and 12.65 ±0.61 Ma (Banská Hodru?a), and apatite (U–Th)/He ages of 14.45 ±0.70 Ma (diorite) and 12.26 ±0.77 Ma (granodiorite) are less than 1 Myr younger than the corresponding zircon U–Pb ages. For both diorite and granodiorite rocks their chronological data thus document a simple cooling process from magmatic crystallization/solidification temperatures to near‐surface temperatures in the Middle Miocene, without subsequent reheating. Geospeedometry data suggest for rapid cooling at an average rate of 678 ±158 °C/Myr, and the exhumation rate of 5 mm/year corresponding to active tectonic‐forced exhumation. The quick cooling is interpreted to record the exhumation of the studied granitic rocks complex that closely followed its emplacement, and was likely accompanied by a drop in the paleo‐geothermal gradient due to cessation of volcanic activity in the area. 相似文献
55.
Rates of erosion and landscape change along the Blue Ridge escarpment,southern Appalachian Mountains,estimated from in situ cosmogenic 10Be 下载免费PDF全文
Colleen L. Linari Paul R. Bierman Eric W. Portenga Milan J. Pavich Robert C. Finkel Stewart P.H.T. Freeman 《地球表面变化过程与地形》2017,42(6):928-940
The Blue Ridge escarpment, located within the southern Appalachian Mountains of Virginia and North Carolina, forms a distinct, steep boundary between the lower‐elevation Piedmont and higher‐elevation Blue Ridge physiographic provinces. To understand better the rate at which this landform and the adjacent landscape are changing, we measured cosmogenic beryllium‐10 (10Be) in quartz separated from sediment samples (n = 50) collected in 32 streams and from three exposed bedrock outcrops along four transects normal to the escarpment, allowing us to calculate erosion rates integrated over 104–105 years. These basin‐averaged erosion rates (5.4–49 m Myr?1) are consistent with those measured elsewhere in the southern Appalachain Mountains and show a positive relationship between erosion rate and average basin slope. Erosion rates show no relationship with basin size or relative position of the Brevard fault zone, a fundamental structural element of the region. The cosmogenic isotopic data, when considered along with the distribution of average basin slopes in each physiographic province, suggest that the escarpment is eroding on average more rapidly than the Blue Ridge uplands, which are eroding more rapidly than the Piedmont lowlands. This difference in erosion rates by geomorphic setting suggests that the elevation difference between the uplands and lowlands adjacent to the escarpment is being reduced but at extremely slow rates. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
56.
57.
Milan Burša 《Earth, Moon, and Planets》1993,62(2):139-144
The exact definition of the tidal potential is given on the basis of the theory of the restricted three-body problem. There are no limitations as regards the perturbing terms in the gravitational fields of the tide forming bodies; andno a priori conditions are needed in the definition. 相似文献
58.
Milan Burša 《Earth, Moon, and Planets》1992,59(3):239-244
Secular Love numbers of the major planets have been determined by solving the first (Dirichlet's) boundary — value problem for the level ellipsoid as the boundary surface. It has been demonstrated that the rotational distortions are responsible for the actual figure of the bodies above. The 6th degree Stokes zonal parameter for Uranus and for Neptune have been predicted. 相似文献
59.
Milan Burša 《Earth, Moon, and Planets》1995,69(1):51-63
Problem of selecting primary parameters has been discussed. Primaries should be defined uniquely, as well as, physically. Since no unique definition for semimajor axis exists, it should be replaced by the geoidal geopotential valueW
0 or by the geopotential scale factorR
0 =GM/W
0, geocentric gravitational constantGM be also primary parameter. Current best estimates of some parameters are given numerically. 相似文献
60.
本文使用穆斯堡尔效应对三个铬铁矿进行了研究,测量了铬铁矿L-1在150K和298K温度下的穆斯堡尔谱和铬铁矿L-2和L-3在298K温度下的谱。使用次近邻效应解释了铬铁矿中的多重Fe~(2+)双峰,并使用二项式分布计算了Cr~(3+)、Fe~(3+)和Al占据次近邻位置的几率。在穆斯堡尔面积和二项式分布计算的基础上做出了Fe~(2+)双峰的指派。铬铁矿L-1谱在150K下进一步分裂,表明用来解释铬铁矿谱的模型是正确的。 相似文献