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31.
测定北方期年代的海底研究JeffHecht参加大洋钻探计划的一个国际地质学家小组收集的新证据表明北半球冰原开始扩展的时间要比通常认为的早5Ma。从海底搜集的沉积物表明,在大约7Ma以前,格陵兰东南部为冰原所覆盖。长期以来,地质学家们认为较寒冷的气候使... 相似文献
32.
阅读足够的文献,恰当的估计文稿的水平,选择专业和档次对口的杂志,论文中明确自己的资料和观点,尤其是与别人不同的观点,力争使高质量的论文刊登在重要杂志上。 相似文献
33.
翟世奎,男,山东聊城市人,1958年1月生。1981年12月毕业于青岛海洋大学(原山东海洋学院),1988年在中国科学院海洋研究所获博士学位,1991年10月在英国剑桥大学完成博士后研究。研究员。1992年5月获“中国科学院海洋研究所优秀青年特殊津贴”,1993年获青岛市“十佳科技青年”荣誉称号,同年获得“中国科学院青年科学家。等奖”和享受“国务院政府特殊津贴”。自1982年起翟世奎研究员先后承担和参加科学院重点课题一项国家基金课题4项。目前,承担国家“八五”科技攻关专题2项,国家自然科学基金课题2项,中国科学院院长基金1项。“现代… 相似文献
34.
《山东海洋学院学报》1984,14(1):20-23
海洋地质学既是海洋学,也是地质学的分支学科。自1960年建系以来,围绕着国家经济发展的需要,结合生产建设和资源调查开展了科学研究工作,取得了一些成果。 相似文献
35.
秦蕴珊,男,山东掖县人,1933年6月生,1956年毕业于北京地质学院。秦蕴珊研究员是我国著名的海洋地质学家。现任中国科学院海洋研究所所长,中国海洋湖沼学会理事长,中国海洋研究委员会主席。《海洋与湖沼》学报主编。他为我国海洋地质学科的创立和发展做出了重要贡献。他对中国陆架沉积作用和海底沉积物的类型、分布及物质组成进行了大量的调查和深入研究,不但从宏观上阐明了沉积物分布的空间格局,而且划分出两种不同时代和不同成因的内陆架和外陆架沉积,并编绘了完整的中国海陆架沉积类型图,建立了中国陆架的海底沉积模式。被国内… 相似文献
36.
J A Vargas-Guzmán 《中国地质大学学报(英文版)》2008,19(1):85-92
An analysis of statistical expected values for transformations is performed in this study to quantify the effect of heterogeneity on spatial geological modeling and evaluations. Algebraic transformations are frequently applied to data from logging to allow for the modeling of geological properties. Transformations may be powers, products, and exponential operations which are commonly used in well-known relations (e.g., porosity-permeability transforms). The results of this study show that correct computations must account for residual transformation terms which arise due to lack of independence among heterogeneous geological properties. In the case of an exponential porosity-permeability transform, the values may be positive. This proves that a simple exponential model back-transformed from linear regression underestimates permeability. In the case of transformations involving two or more properties, residual terms may represent the contribution of heterogeneous components which occur when properties vary together, regardless of a pair-wise linear independence. A consequence of power- and product-transform models is that regression equationswithin those transformations need corrections via residual cumulants. A generalization of this result isthat transformations of multivariate spatial attributes require multiple-point random variable relations. This analysis provides practical solutions leading to a methodology for nonlinear modeling using correct back transformations in geology. 相似文献
37.
The indicator kriging (IK) is one of the most efficient nonparametric methods in geo-statistics. The order relation problem in the conditional cumulative distribution values obtained by IK is the most severe drawback of it. The correction of order relation deviations is an essential and important part of IK approach. A monotone regression was proposed as a new correction method which could minimize the deviation from original quintiles value, although, ensuring all order relations. 相似文献
38.
Based on the theory of thermal conductivity, in this paper we derived a formula to estimate the prolongation period (AtL) of cooling-crystallization process of a granitic melt caused by latent heat of crystallization as follows:△tL=QL×△tcol/(TM-TC)×CP where TM is initial temperature of the granite melt, Tc crystallization temperature of the granite melt, Cp specific heat, △tcol cooling period of a granite melt from its initial temperature (TM) to its crystallization temperature (Tc), QL latent heat of the granite melt.
The cooling period of the melt for the Fanshan granodiorite from its initial temperature (900℃) to crystallization temperature (600℃) could be estimated -210,000 years if latent heat was not considered. Calculation for the Fanshan melt using the above formula yields a AtL value of -190,000 years, which implies that the actual cooling period within the temperature range of 900°-600℃ should be 400,000 years. This demonstrates that the latent heat produced from crystallization of the granitic melt is a key factor influencing the cooling-crystallization process of a granitic melt, prolongating the period of crystallization and resulting in the large emplacement-crystallization time difference (ECTD) in granite batholith. 相似文献
The cooling period of the melt for the Fanshan granodiorite from its initial temperature (900℃) to crystallization temperature (600℃) could be estimated -210,000 years if latent heat was not considered. Calculation for the Fanshan melt using the above formula yields a AtL value of -190,000 years, which implies that the actual cooling period within the temperature range of 900°-600℃ should be 400,000 years. This demonstrates that the latent heat produced from crystallization of the granitic melt is a key factor influencing the cooling-crystallization process of a granitic melt, prolongating the period of crystallization and resulting in the large emplacement-crystallization time difference (ECTD) in granite batholith. 相似文献
39.
More than 40 national and regional geochemical mapping projects in the world carried out from 1973 to 1988 do not conform to common standards. In particular they have many analytical deficiencies. In the period 1988 to 1992, the International Geochemical Mapping project (Project 259 of UNESCO's IGCP Program) prepared recommendations designed to standardize geochemical mapping methods. The analytical requirements are an essential component of the overall recommendations. They included the following: 71 elements should be analyzed in future mapping projects; the detection limits of trace and ultratrace elements must be lower than the corresponding crustal abundances; and the Chinese GSD and Canadian STSD standard sample series should be used for the correlation of global data. A proposal was also made to collect 5000 composite samples, at very low sampling densities to cover the whole Earth's land surface. In 1997 an IUGS Working Group on Global Geochemical Baselines was formed to continue the work which began with IGCP 259. From 1997 up to now, new progress has been made especially in China and FOREGS countries under the aegis of this working group, including the study of suitable sampling media, development of a multi-element analytical system, new proficiency test for selection of competent laboratories and role of wide-spaced mapping in mineral exploration. One of the major problems awaiting solution has been the inability of many laboratories to meet the IGCP recommendations to generate high quality geochemical maps. Fortunately several laboratories in China and Europe have demonstrated an ability to meet the requirements and they will be well placed to render technical assistance to other countries. 相似文献
40.
LIU Luofu HUO Hong GUO Yongqiang CHEN Lixin LI Shuangwen ZHAO Yande LI Yan WANG Ping CHEN Zhijun 《中国地球化学学报》2008,27(1):1-8
The results presented in this paper indicated that the carbazole-type compounds have high thermal stability and also show stability in oxidation and bio-degradation. This kind of compounds still has high concentrations and a complete distribution in the analyzed dry asphalt samples, showing that they are particularly useful in the study of hydrocarbon migration of the paleo-pools. The difference in the contents of nitrogen compounds in the Silurian dry asphalts from the Awati, Tabei and Tazhong areas is attributed to the difference in the extent of oxidation and (or) bio-degradation for the areas; the Awati and Tabei areas underwent relatively strong oxidation and bio-degradation. During the first stage of hydrocarbon pool formation in the Silurian system in the Tazhong and Tabei areas of the Tarim Basin (at the end of the Silurian period) and at the second stage in the Awati area (in Permian), the hydrocarbons experienced a long-distance migration. 相似文献