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681.
Presented in this paper are some primary data on the temperature, stratigraphical altitude and thickness of a certain uranium ore deposit. Taking these data as the parameters for the temperature, pressure and geochemical conditions of uranium mineralization under ideal geological conditions which constitute a finite variable series, in conjunction with the catastrophe theory developed by Rene Thom (1968), we have proposed a swallow-tail model fit to uranium mineralization. This model provides insight into the mechanism of uranium mineralization. Our study shows that the process of uranium mineralization is a discontinuous or catastrophic event. Temperature and pressure are considered important thermodynamic conditions which control the distribution pattern of uranium mineralization, and the principle of temperature-pressure correspondence for uranium mineralization has been also derived. Geological bodies of minerogenetic importance serve as favourable geochemical media for capturing ore-forming materials. Uranium mineralization of commercial importance depends on a delicate coupling between temperature,pressure, and geochemical condition. The loci of uranium mineralization in the model constitute the surfaceK, referred to as the surface of enrichment-mineralization, on which minerogenetic domain is expected. The model provides quantitatively clues to the process of uranium mineralization, i.e., a process from quantitative to qualitative changes. 相似文献
682.
By performing error analysis of the information from the 48-hr forecasting charts of the 500-hPa fields by the B model over eastern Asia in the period of July to September 1982 and expansions of the height fields of westerlies and the subtropical zone by use of the Chebyshev polynomial and EOF, respectively, a scheme is developed for predicting the synchronous STH coefficient (i. e. time coefficient) in terms of the Chebyshev one, thus making possible statistical forecasting of the 500-hPa subtropical field within 48 hr. Tests with independent samples indicate that, to a certain extent, this scheme can be used in operational prediction as a reference. 相似文献
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山西寿阳—阳泉地区石炭—二叠系沉积环境及其沉积特征 总被引:1,自引:0,他引:1
本区石炭—二叠系是在海湾背景下发育的一套由滨海平原—三角洲平原—冲积平原沉积组成的海退层系。主要沉积环境是三角洲平原,其上部为冲积平原包括网状河和辫状河;下部为海湾(或分支间湾)、潮下碳酸盐岩、潮间介壳滩、碎屑岩潮坪及滨海沼泽湿地等。三角洲为河控浅水三角洲。上述沉积环境,随海水退却在时空上具明显的规律性变化。 相似文献
686.
Zhengzhang Tao 《中国地球化学学报》1986,5(1):34-54
Described in the present paper is the evolution of the concept of “clarke” introduced by A. E. Fersman. Based on the data
available in literature, the atomic clarkes of chemical elements in the earth’s crust were computed and the logarithmic distribution
curves were drawn by means of the micro-computer (PC-1500). Volume percentages of the chemical elements in the orust were
also computd and the legarithmic curves also drawn. Finally, the isotopic abundances of each element in the crust were computed. 相似文献
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