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991.
This paper discusses origin and charging directions of oil fields on the Shaleitian Uplift, Bohai Bay basin. The Shaleitian Uplift is a footwall uplift surrounded by three sags containing mature source rocks. The origins of the four oil fields on the Shaleitian Uplift, both in terms of source rock intervals and in terms of generative kitchens, were studied using biomarker distributions for 61 source rock samples and 27 oil samples. Hierarchical cluster analysis using 12 parameters known to be effective indicators of organic matter input and/or depositional conditions allowed the identification of six oil types or classes. These six oil classes could then be linked to three distinct source rock intervals ranging in age from 43.0 Ma to 30.3 Ma. The third member (43.0–38.0 Ma in age) and first member (35.8–32.8 Ma) of the Eocene Shahejie Formation, and the third member of the Oligocene Dongying Formation (32.8–30.3 Ma) each sourced one class of oil. The other three classes represent mixtures of oil generated from multiple source rock intervals. Traps on the Shaleitian Uplift were charged in the east by oil generated from the Eocene Shahejie Formation in the Bozhong Sag, in the southeast by oil generated from the Eocene Shahejie and then Oligocene Dongying formations in the southwestern part of the Bozhong Sag and/or in the eastern part of the Shanan Sag, and in the southwest by oil generated from the Eocene Shahejie Formation in the western part of the Shanan Sag. The estimated migration distances range from less than 5 km to about 20 km. The compositional heterogeneity within fields and multiple-parameter comparisons between oils from nearby wells in different fields have proven to be a powerful tool to determine the in-filling histories of oil fields in cases where multiple source rock intervals and multiple generative kitchens exist.  相似文献   
992.
GRACEʱ���������ĸ�˹ƽ���о�   总被引:1,自引:0,他引:1  
??????????????????????GRACE??????????????????????2006??1????2?μ??????????仯???о?????????????????????????????????????????????Σ?????????γ??????????????????????????????????????????????????????????????????????????????????????  相似文献   
993.
黑龙江省农业气候背景分析   总被引:4,自引:0,他引:4  
概述了黑龙江省的主要气候特征,介绍了主要农业气候资源状况,分析了气候变化与发展趋,并初步探讨了气候变化对黑龙江省农业生产及生态环境的可能影响.  相似文献   
994.
Chapman 等大气潮汐专家认为,地球表面的太阳潮汐全口波被抑制,而半口波被放大,这个结论一直延续数十年。然而,根据南极地区三个站的资料计算表明:在南极地区,地面太阳气压潮汐的全日波远强于半日波,这与高登义等(1986)应用我国205个台站资料计算结果是一致的。 上述结果表明,南极地区近地面太阳气压潮汐全日波并未被抑制,而半日波也未被放大。这与Chapman等人的结论是不一致的。  相似文献   
995.
This study presents results of the pilot experiments made with new parametric multi-site multi-variable stochastic daily weather generator (WG) SPAGETTA. The experiments are performed for eight European regions and we focus on spatial characteristics of temperature. The WG is calibrated using the gridded weather data E-OBS. In evaluating the generator, the spatial and temporal temperature autocorrelations derived from the synthetic series were found to perfectly fit the values derived from the calibration data. Next, the WG is validated in terms of the frequency of “spatial hot days” and the annual maximum length of “spatial hot spells”. The results indicate a very good correspondence between characteristics derived from synthetic and calibration data. As part of the validation tests, the performance of the WG is compared with a regional climate model (RCM), which shows a similar performance as the generator. In a final experiment, the use of the WG for the future climate is demonstrated, the WG parameters (including the temperature autocorrelations) calibrated with the observed data are modified according to the RCM-based changes in these parameters. While analyzing synthetic series produced with the modified generator, we discuss partial impacts due to changes in individual WG parameters on the spatial hot days and spells. We show that the impacts are mainly (but not only) due to changes in temperature averages. The projected changes in temperature autocorrelations have also some impacts, larger for the spatial hot spells than for the spatial hot days. Climate change impacts on spatial hot days/spells based on the WG are compared with impacts based on the RCM, and we conclude that the differences are mainly due to simplifying assumptions adopted in our pilot experiment.  相似文献   
996.
The Earth-Climate System Model (ECSM) is an important platform for multi-disciplinary and multi-sphere integration research, and its development is at the frontier of international geosciences, especially in the field of global change. The research and development (R&D) of ECSM in China began in the 1980s and have achieved great progress. In China, ECSMs are now mainly developed at the Chinese Academy of Sciences, ministries, and universities. Following a brief review of the development history of Chinese ECSMs, this paper summarized the technical characteristics of nine Chinese ECSMs participating in the Coupled Model Intercomparison Project Phase 6 and preliminarily assessed the basic performances of four Chinese models in simulating the global climate and the climate in East Asia. The projected changes of global precipitation and surface air temperature and the associated relationship with the equilibrium climate sensitivity under four shared socioeconomic path scenarios were also discussed. Finally, combined with the international situation, from the perspective of further improvement, eight directions were proposed for the future development of Chinese ECSMs.  相似文献   
997.
The effects of organic matter, humic acid and Tween-80 on decabromodiphenyl ether (BDE-209) behavior in soil columns were investigated. The BDE-209 transport was simulated in 4-cm-length soil columns whether organic matter was added or not. A high concentration of BDE-209 was washed out of the soil column in the presence of 500 mg L?1 of Tween-80 for forming and suspending contaminated soil colloids in more than 4-cm-length ones (especially in 10-cm-length ones). While the humic acid was to facilitate BDE-209 adsorption onto soil particles (like soil colloids), Tween-80 was to enhance BDE-209 movement in porous media. The significant concentration averaged from 0.2 to 0.1 μg L?1 in soil columns of length from 10 to 24 cm with Tween-80 addition by comparing the estimated marginal means (p < 0.05, SPSS). Contrasted with humic acid-binding BDE-209 in soil particles, Tween-80 could carry contaminant soil colloids into deeper layers and even affect the final effluents of 25-cm-length columns. It was visibly presented that the BDE-209 concentration in the effluents was mainly induced by Tween-80. Thus, BDE-209 was carried by soil colloids to transport and pollute longer and wider soil distance with the help of the effective promoters and stabilizers of Tween-80 and humic acid in soil matrix.  相似文献   
998.
Effects of sodium acetate and glucose on the microbes from the simultaneous flue gas desulfurization and denitrogenation tandem biotrickling process were respectively investigated. For the acidophiles, although the impacts of the carbon sources on the total microbial growth and nitrogen conversion in the medium were slight, the sulfite oxidation rate was obviously improved. The highest sulfite ion oxidation ratio in 48 h was up to 47.2 % as 258.08 mmol L?1 sodium acetate was added in the medium. For the neutrophiles, the two carbons promoted the total microbial growth, but only sodium acetate could enhance the nitrite consumption significantly. The best nitrite consumption rate in 48 h could reach to 86.7 % with 258.08 mmol L?1 sodium acetate. It provides valuable information for the development of biological SO2 and NO x simultaneous purification process.  相似文献   
999.
Flood classification is the fundamental problem of flood risk analysis and plays an important role in flood disaster risk management. Considering the fact that flood classification is a problem of multi-attribute and multi-stage fuzzy synthetically evaluation, this paper mainly proposed the weighted fuzzy kernel-clustering algorithm (WFKCA) with adaptive differential evolution algorithm (ADE) to solve this problem. Firstly, WFKCA is detailed introduced, and then the differential evolution algorithm (DE) is applied for the fuzzy clustering, thus to obtain the better results. Taking into consideration the disadvantage of DE, ADE is present after the introduction of DE. Finally, the combination of WFKCA and ADE is applied for flood classification, and the results demonstrated the methodology is reasonable and reliable, thus provide a new effective approach for flood classification.  相似文献   
1000.
The main goal of the gamma-ray spectrometer(GRS) onboard Chang'E1(CE-1) is to acquire global maps of elemental abundances and their distributions on the moon,since such maps will significantly improve our understanding of lunar formation and evolution.To derive the elemental maps and enable research on lunar formation and evolution,raw data that are received directly from the spacecraft must be converted into time series corrected gamma-ray spectra.The data correction procedures for the CE-1 GRS time series...  相似文献   
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