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51.
碳酸盐岩中有机质组成特征分析 总被引:2,自引:0,他引:2
对碳酸盐岩有机质组分进行分类时,有两种分类标准,一是主要采用煤岩学方法,二是采用孢粉学研究方法。本文使用煤岩学方法作为标准,对碳酸盐岩有机质的组成特征进行分析。按有机质来源和有机组分光性和形态等方面差别划分为内源有机质、次生有机质和陆源有机质三类。内源有机质类中分腐泥组和动物有机组,前者主要来源于菌藻类,后者则主要来源于浮游动物有机体;次生有机质中区分出微粒体、有机包裹体、沥青;陆源有机质类分类术语仍沿用煤显微组分分类系统和术语。碳酸盐岩烃源岩的有机质主要为腐泥型,有机质来源以低等藻类为主,且有机质组成特征与碳酸盐岩烃源岩的地质年代有关。碳酸盐岩还存在着差异演化的特征。 相似文献
52.
We highlighted the flexibility of using unstructured mesh together with the local refinement by a resistivity model with complicated topography. The effect of topography is emphasized. Based on this, we calculated a specific class of layered models and found that the accuracy is not always satisfactory by utilizing the standard approach. As an improvement, we employed the layered earth as the reference model to calculate the wavenumbers. The comparison demonstrates that the accuracy is considerably improved... 相似文献
53.
目前,Inpho全数字摄影测量系统针对航空三线阵影像具有较为成熟的处理流程。但是随着摄区环境和飞行成本要求的不断提高,航线方向不再局限于坐标轴方向,斜飞模式逐渐增多。本文在Inpho系统DOM影像制作原理的基础上,对比研究交互式方位角定义在ADS影像生产中的普遍适用性,进一步优化Inpho系统针对ADS数据的解决方案。 相似文献
54.
LIU Hanlong DAI Huichao Susumu IAI
Professor Geotechnical Engineering Research Institute Hohai University Nanjing China.
Senior Engineer China Yangtze Three Gorges Project Development Corporation Yichang China.
Doctor Port Harbour Research Institute Ministry of Transport Nagase Japan. 《中国海洋工程》1999,(1)
—Effective stress analysis is performed to evaluate the residual displacement of a caissonquaywall during 1994 Hokkaido-Toho-Oki Earthquake and 1993 Kushiro-Oki Earthquake.Theconstitutive model used in this study is a multiple shear mechanism type defined in strain space and cantake into account the effect of rotation of principal stress axis.The earthquake accelerations recorded atthe outcropping rock during the earthquake are used as input bedrock motion.The results of finite ele-ment analysis are in good agreement with the observed behaviour of the quaywall.The analysis also indi-cates that liquefaction and high excess pore water pressure have a significant effect on the deformation ofthe caisson.Soil improvement is speculated as the most reliable measures against liquefaction.The influ-ence of soil improvement and the reasonable improved area are discussed in the paper. 相似文献
55.
地震信息对薄砂岩储层特性的描述 总被引:1,自引:0,他引:1
近年来,以地震信息为主进行油气藏描述,这是当前对石油勘探的重点攻关课题.本文结合我国陆上和海域部分油田或含油气构造的实际资料,运用地震信息为主,结合测井、地质及钻井等资料,对储层进行综合解释。同时,提出了用多地震信息计算薄层厚度的基本公式,根据地区性岩性和地震资料的差异,使用了确定性地质统计和Coringing分析两种方法进行储层物性参数的预测,文中给出大量的实例说明各种储层参数描述方法和应用效果。 相似文献
56.
Chih-Pei Chang 《Pure and Applied Geophysics》1977,115(5-6):1089-1109
Summary Some important theoretical problems of the planetary-scale monsoons which have arisen from recent advances of observational studies are reviewed. These include: (1) the requirement of a strong damping mechanism in the planetary scale vorticity budget of summer monsoon and a similar but weaker requirement for the winter monsoon; (2) the localized barotropic instability of the summer monsoon which is a result of the strong zonal asymmetry of the planetary-scale flow and causes significant nonlinear energy conversions; and (3) the oscillations of the planetary-scale monsoons. It is pointed out that these problems are inter-related and their understanding is also important for the proper simulation of other scales of motion of the monsoon circulation. 相似文献
57.
Chang Jen-hu 《GeoJournal》1980,4(5):437-445
Several aspects of energy budget and water balance problems in SE Asia and New Guinea are discussed and a new map showing the distribution of global radiation in SE Asia and New Guinea is presented. Potential evapotranspiration rates are calculated by the Penman equation and are compared with monthly rainfall to determine the length of the hydrological growing season. Potential rice yields are estimated based on a formula developed by the International Rice Research Institute. The extremely low maize yields of Asian humid tropics are explained by unfavorable climatic conditions, particularly high night temperature.The editor recommends to look in GeoJournal 3.2, 3.6, and 4.1 for further articles related to the present paper. 相似文献
58.
59.
This study presents a probabilistic neural network (PNN) technique for predicting the stability number of armor blocks of breakwaters. The PNN is prepared using the experimental data of Van der Meer. The predicted stability numbers of the PNN are compared with those of previous studies, i.e. by an empirical formula and a previous neural network model. The agreement index between the measured and predicted stability numbers by PNN are better than those by the previous studies. The PNN offers a way to interpret the network's structure in the form of a probability density function and it is easy to implement. Therefore, it can be an effective tool for designers of rubble mound breakwaters. 相似文献
60.