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排序方式: 共有683条查询结果,搜索用时 675 毫秒
611.
地球岩石中稀有气体研究进展 总被引:3,自引:0,他引:3
简要回顾了90年代以前在地球岩石稀有气体研究领域取得的成果,总结了90年代以来该领域的最新成就,最后指出了存在的问题。 相似文献
612.
我国不同赋存状态烃类气体的研究现状与展望 总被引:5,自引:0,他引:5
不同赋存状态烃类气体(包括游离的天然气、吸附气、酸解气、水溶气和油溶气)研究对于烃源岩评价、天然气成因判识、油气复合关系研究,油气源对比和油气勘探均具有十分重要的理论和应用价值。我国经过“六五”、“七五”和“八五”期间组织天然气地学攻关,在该领域内取得了较大进展。综述了我国不同赋存状态烃类气体的研究现状,分析了研究中存在的几个问题,并展望了其理论和应用前景。 相似文献
613.
In this paper,a two-dimensional(2-D)coupled stratospheric-tropospheric dynamical-radiative-chemical model has been developed,and some preliminary results have been given.From theseresults we can see that the latitude-height distribution characteristics and the seasonal variation ofthe dynamical fields such as atmospheric temperature,wind field,etc.can be effectively simulatedby using this model;and the modelled latitude-height distribution of trace gases gives theirdistribution characteristics and seasonal variation rather well.All of these are testimony to thestrong ability of the model. 相似文献
614.
Peter J. Valbracht Thomas Staudacher Alex Malahoff Claude J. Allgre 《Earth and Planetary Science Letters》1997,150(3-4):399-411
We report new noble gas fusion and crushing data for six pillow rim glasses, recovered between 3 and 5 km water depth on the south rift zone of Loihi Seamount, Hawaii. Helium abundances of the glasses vary from 0.3 to 2.3 μcc/g, with 4He/3He ratios between 30000 and 27000 (24–27 RA), similar to previously reported values. The neon data form a correlation line which is similar to the Loihi-Kilauea line reported by Honda et al. [1], but extends to much higher ratios, up to 12.9 and 0.0382 for the 20Ne/22Ne and 21Ne/22Ne ratios, respectively. This provides conclusive evidence for the suggestion that the Hawaiian plume, thought to originate in the lower mantle, has a solar-like 20Ne/22Ne composition [1], but a slightly higher 21Ne/22Ne ratio. 40Ar/36Ar ratios of the deep rift-zone glasses are as high as 2600, and show a positive correlation with neon isotopic ratios. In contrast to neon and argon, all xenon isotopic compositions are isotopically indistinguishable from air, which either suggests preferential atmospheric contamination of xenon, or could indicate an atmospheric xenon isotopic composition for the lower mantle. 相似文献
615.
Material sources of escaped gases from Tianchi volcanic geothermal area, Changbai Mountains 总被引:4,自引:0,他引:4
On the basis of the chemical components and stable isotopic compositions of escaped gases from the Tianchi volcanic geothermal
area, the material sources of these gases are discussed, presenting that they are mainly derived from the residual mantle-derived
magma in the crust; Changbai geothermal area may be directly interlinked with the eruption canal in history; there is a stable
reservoir of the geothermal water and the deep-seated gases under the Changbai geothermal area, with water temperature of
the reservoir being about (166 ± 9)°C.
Project supported by the National Natural Science Foundation of China. 相似文献
616.
A. Longhetto S. Ferrarese C. Cassardo C. Girau F. Apadttl P. Bacci P. Bonelli A. Marzorati 《大气科学进展》1997,14(3):309-322
Middle tropospheric CO2 air concentrations, measured during a four year observation period at an Alpine Station (Plateau Rosa, Italian North-West Alps, 3480 m a.s.l.), have been correlated with the relevant synoptic air trajectories crossing the observation site. Meaningful relationships have been found among average curvature, altitude and potential temperature of clusters of homogeneous trajectories and their related CO2 concentrations measured at Plateau Rosà, allowing an objective identification of weather conditions giving rise to fully mixed air masses corresponding to background atmospheric CO2 levels. Air trajectories were calculated by using the wind speed fields provided by the ECMWF objective analysis. As during the analysis period a change of the ECMWF model resolution occurred (from T106 to T213), the study was also carried out in the sub-periods respectively preceding and following this change (in September 1991). Even if some features of the wind field turned out to be statistically different in the two sub-periods, nevertheless the differences on the trajectory patterns were small enough to keep almost unchanged all conclusions drawn for the whole four-year period. 相似文献
617.
618.
619.
王水辰 《中国海洋大学学报(自然科学版)》1995,(3)
作者根据Keeling等人提出的1970~1988年大气CO2含量随时间变比进行统计,指出大气CO2含量按指数变化递增。据此.对近年大气CO2含量进行预测,到2050年时将增至454×10-6,较目前增加约30%。由于大气CO2分压上升,导致CO2向海洋转移、作者采用Li提出的指数变化模式,以Holland给出的海水中无机碳逗留时间8.0×104年代入计算。到2050年时,海水碳酸盐系统仅可容纳来自大气的CO21.1×1010t。因此必须引起人们控制CO2向大气的排放。鉴于计算过程中未考虑海水有机生物体的影响及颗粒CaCO3对缓冲CO2所作贡献,因此,实际情况会好于本文计算结果。 相似文献
620.
TANG Youjun WEN Zhigang 《中国地球化学学报》2007,26(3):325-328
The geochemical characteristics of natural gases discovered in the Bozhong Depression are systematically described in this paper. The natural gases are composed mainly of hydrocarbon gases. Natural gases occurring in the Paleogene and older reservoirs are wet gases, whereas those in the Neogene reservoirs are dry gases. Methane and ethane in the gases are significantly different in carbon isotopic composition. The methane carbon isotopic composition of the gases in structure BZ28-1 and the ethane carbon isotopic composition of the gases in structure QHD30-1 are characterized by the heaviest values, respectively. The natural gases are in the mature to highly mature stages. The hydrocarbon gases are of organic origin and can be classified as oil-type gases, coal-derived gases and mixed gases with the third one accounting for the major portion. 相似文献