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71.
72.
The Cone-in-Cone Structure and Its Origin 总被引:1,自引:0,他引:1
Morphostructural investigation of carbonate cone-in-cone formations allows to conclude that they belong to self-organizing (dissipative, according to I. Prigogine's terminology) systems of the geological past formed in a thermogradient field at the expense of energy of heat and mass transfer (Prigogine and Stengers, 1984). First, the fluid-convective metasomatic hypothesis unites and reconciles the most well-known hypotheses that previously seemed to be incompatible and transforms them to rather consistent particular cases of a more intricate multistage geological phenomenon. Second, it helps to identify the morphologically and genetically analogous noncarbonate structures that mimic biogenic ones. The probable indicative role of cone-in-cone structure in the mapping of fluid-conducting systems is a consequence of the proposed hypothesis. 相似文献
73.
74.
Source scaling of intermediate-depth Vrancea earthquakes 总被引:3,自引:0,他引:3
75.
This paper goes some way towards redressing the lack of geographical literature on charity through exploring the geography of the British domestic charitable sector. The size and geography of the third sector is outlined, followed by an analysis of how almshouses can be understood as inherently geographical and deeply embedded in local social networks of inclusion as well as exclusion. 相似文献
76.
Studies evaluating the reproductive pattern of Mytilus edulis L. were conducted in western and eastern Iceland at two sites at about the same latitude but with different temperature regimes. Mussels were sampled once or sometimes twice a month during two years in Breidifjördur, western Iceland and one year at Mjoifjördur, eastern Iceland. Gonad development was monitored by microscopic observation of thin sections of the gonads. The initiation of gonad development was observed in January in Breidifjördur while in Mjoifjördur some of the animals started developing gonads in October, a month before spawning was over in the population. Spawning started in late June or July, peaked in August and continued until November at both sites. Nutrient reserve stores seemed to be limited and used for initiation of gonad development in winter but were not sufficient for maturation of the gonads. The main growth of the gonads occured in spring in conjunction with phytoplankton blooming and renewal of food resources. 相似文献
77.
Astrakhantsev G. P. Minina T. R. Petrova N. A. Poloskov V. N. Rukhovets L. A. 《Water Resources》2003,30(2):209-220
A zoobenthos submodel is included in an ecosystem model. The new model is used to assess the role of zoobenthos in the phosphorus exchange at the water–bed interface, in particular, the phosphorus cycle in the water body ecosystem is described more accurately. The calculated zoobenthos distribution over the bed of a lake can be used in modeling the lake ichthyocenoses. 相似文献
78.
79.
A canonical theory for short GPS baselines.
Part II: the ambiguity precision and correlation 总被引:1,自引:0,他引:1
P. J. G. Teunissen 《Journal of Geodesy》1997,71(7):389-401
The present contribution is the second of four parts. It considers the precision and correlation of the least-squares estimators
of the carrier phase ambiguities. It is shown how the precision and correlation of the double-differenced ambiguities as well
as of the widelane ambiguities are effected by the observation weights, by the number of satellites tracked, by the number
of observation epochs used, and by the change over time of the relative receiver-satellite geometry. Also the ability of the
widelane transformation to decorrelate and to improve the precision is investigated.
Received: 16 July 1996 / Accepted: 14 November 1996 相似文献
80.
Pre-weighed blocks of a Jurassic Limestone were exposed on the ground surface in the coastal Namib Desert for a period of 2 years. The environment is both salty and foggy. Some of the blocks suffered extensive disintegration, and laboratory analyses (including geochemistry, XRD and SEM) indicate that the weathered samples have a high halite (sodium chloride) content. Cycles of wetting and drying associated with the frequent fog events of the area cause cycles of halite crystallization. Rocks exposed at the surface absorb salts from the surrounding desert surface and then disintegrate, contributing to planation of the landscape. 相似文献