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71.
《The Professional geographer》2012,64(1):121-130
Despite their small size, in both area and population, many different languages are spoken by residents of the small island developing states (SIDS). Most of these languages are used by very few people. With one exception, the remaining forty-nine SIDS have one or more official languages. Slightly over 62 percent of the eighty official languages are those of former colonial rulers. Of the total of 1,500 languages, the Weaver’s minimum positive deviation method identified only 106 as dominant languages. These languages are spoken by more than 96 percent of the population in the SIDS. The data further show that twenty-eight of the fifty SIDS are monolingual and the remaining twenty-two are either bilingual or multilingual. Surprisingly, in many monolingual SIDS, the official language is not the dominant language. The dominant languages of these nations were first categorized as monolingual, bilingual, and multilingual and then were analyzed by their location, area, and population size. No statistically significant variation was found between them. Reasons for these conditions are explained, and future research direction is provided. Key Words: bilingual, dominant languages, monolingual, multilingual, small island developing countries. 相似文献
72.
Atle Nesje Svein Olaf Dahl John A. Matthews Mark S. Berrisford 《Journal of Paleolimnology》2001,25(3):329-342
To extend the historical record of river floods in southern Norway, a 572-cm long sediment core was retrieved from 42 m water depth in Atnsjøen, eastern Norway. The sediment core contains 30 light gray clastic sediment layers interpreted to have been deposited during river floods in the snow/ice free season. In the upper 123 cm of the core, four prominent flood layers occur. The youngest of these overlap with the historical record. The thickest (flood layer 5) possibly reflects a general increase in river-flood activity as a result of the post-Medieval climate deterioration (lower air temperatures, thicker and more long-lasting snow cover, and more frequent rain/snow storms) associated with the Little Ice Age. The most pronounced pre-historic flood layers in the core were, according to an age model based on linear regression between eleven bulk AMS radiocarbon dates, deposited around 4135, 3770, 3635, 3470, 3345, 2690, 2595, 2455, 2415, 2255, 2230, 2150, 2120, 1870, 1815, 1665, 1640, 1480, 1400, 1380, 1290, 935, 885, 670, 655 and 435 cal. BP (BP = AD 1950). The mean return period of the river flood layers is, according to the linear regression age model, ~ 150 ± 30 cal. yr (mean ± 1 S.E.). 相似文献
73.
The Kuhmo greenstone belt (Eastern Finland) is mainly formed by mafic volcanic rocks and metasediments. Although the geological observations indicate that this belt appears as a supracrustal synform overlying a gneissic basement, its deep structures are actually unknown. The present gravity study intends to provide a better understanding of these structures. Interpretation of gravity anomalies of the Kuhmo belt, using two-dimensional modelling suggests that the structures of the belt are controlled by granitoids diapirs. Most of the calculated models show that the belt displays in section pocket-like shapes (purses) terminated by a gully-shape close to the surface. This particular geometry corroborates the hypothesis of a gravitational formation with the heavy volcanic material sinking in a light sialic crust. To cite this article: M. Jaffal et al., C. R. Geoscience 335 (2003). 相似文献
74.
Trapped-gas content in natural porous media, also called residual gas saturation (Sgr), corresponds to the imbibition end-point. To define the parameters controlling Sgr, two parameters were studied: the influence of rock characteristics (on 400 sandstone samples) and initial gas saturation (Sgi), on the basis of 60 experimental curves between Sgr and Sgi. Based on an extensive experimental database, this study establishes the dominant influence of microporosity on trapped gas saturation, and indirectly that of the contained clays. To cite this article: K. Suzanne, J. Billiotte, C. R. Geoscience 336 (2004). 相似文献
75.
北天山山前乌鲁木齐—乌苏地区的构造变形特征 总被引:2,自引:0,他引:2
北天山山前乌鲁木齐—乌苏地区的构造变形,是在挤压兼左行剪切作用下形成的.根据皱皱构造的排列组合、地层组成、变形强度及构造线等特征,将本区划分为五个构造带,分属于两个构造系.其中小渠子构造带的成因与博格达山活动相关,属于另一个构造系.其四余个构造带组成独立的玛纳斯构造系,叠加在燕山期构造之上. 相似文献
76.
Mechanical analysis of en echelon structure and its significance of controlling earthquakes 总被引:1,自引:0,他引:1
MechanicalanalysisofenechelonstructureanditssignificanceofcontrollingearthquakesXin-ShengXIE(谢新生)andXiao-PingRUAN(阮小平)(Instit... 相似文献
77.
The paper deals with the mechanical origin and rules ofen echelon folds and their secondary fractures by means of elastic stability theory and nonlinear fracture criterion. Obtains the quantitative
relations amongen echelon angles ofen echelon folds, ratios of boundary stresses anden echelon pitches of shear zone under an action of general boundary forces (tension shear, pure shear or compression shear). As an
applied example, the paper researches the displacement field, stress field, distortion energy distribution, state of secondary
fractures and energy released by fracturing ofen echelon fold structure developed at the east foot of Taihang Mountain. The results of research show that maximum principal (compressive)
stresses, maximum shear stresses, high value area of distortion energy are in the nuclear parts ofen echelon folds. In these parts compressive fractures were easily developed in approximately parallel with fold axis. So it is verified
that the secondary fracture ofen echelon folds is a mechanism controlling a strong earthquake. 相似文献
78.
The paper analyses a list of thirty-four Poles, listeners to the mineralogy lectures given by R.-J. Haüy at MNHN in Paris. These students played an important role in the history of Polish Earth Sciences (S. Staszic and F. Drzewiński), but also in other scientific fields (J. Markowski, I. Ab?amowicz, F. Drzewiński, M.A. Paw?owicz, J.K. Skrodzki, E.K. Nowicki), and even in political and cultural life of Poland (A. Downarowicz, J. Weyssenhoff, S. Plater, J. Bieliński, F. Potocki). This paper presents later relations between R.-J. Haüy and his Polish students. A possibility of the Poles' attendance to mineralogy lectures given at other Parisian scientific institutions, like the ‘École des mines’ and the ‘College de France’, is also discussed. To cite this article: R. Tarkowski, P. Daszkiewicz, C. R. Geoscience 338 (2006). 相似文献
79.
IntroductionMet(1995,1996)presentedhard-inclusionearthquakepreparationmodebasingonintraplatemacroseismicityandtempo-spatialevolutioncharacteristicsofprecursoryabnormalfieldssuchasseismicitygapandhighQvalueappearinginawideareaaroundepicenterbeforestrongearthquakes.Somedeepstructure,mechanicalanalysisandrockmechanicaltestconcernedhaveprovidedsupportingevidenceforthemode.Oneofthemostimportantachievementsofmodernseismologyisconfirmingthatearthquakes(especiallyforshallowfocusshocks)causedbyfaultext… 相似文献
80.