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991.
对贡嘎山南坡洪坝—湾坝地区的三叠纪地层,在剖面上进行详细的沉积学研究及其横向追踪后,确定了5个层序界面,划分出4个层序,建立了层序地层格架及岩石地层格架。本文主要叙述了各层序内沉积体系域的特征。 相似文献
992.
Cover systems are widely used to safeguard landfills and contaminated sites. The evaluation of the water balance is crucial
for the design of landfill covers. The Hydrologic Evaluation of Landfill Performance (HELP) model of the US Environmental
Protection Agency was developed for this purpose. This paper discusses some limitations of version 2 of this model and some
operational difficulties for the use of this model in Germany, which has been developed for the United States. The model results
are tested against field data of the water balance, measured on test fields on the Georgswerder landfill in Hamburg. Theoretically,
HELP considers gravitational forces as driving forces of water flow only. Therefore capillary barriers cannot be simulated.
Furthermore, the formation of and the flow through macropores are not considered, a main critical process that the diminishes
the effectiveness of compacted soil liners. In the output comparison, the matching of measured and simulated data is quite
good for lateral drainage, but failed for surface runoff and liner leakage through compacted soil liners. A further validation
study is planned for HELP version 3 using a broader range of test field data.
Received: 10 January 1995 · Accepted: 14 November 1995 相似文献
993.
A recent early diagenetic banded iron-manganese mud has been forming underground in a closed lead-zinc mine for approximately 40 years. The processes leading to the banded structure of the precipitate were studied during a period of 2 years. Therefore, 19 physical and chemical parameters were measured regularly in short intervals. The resulting time series were analysed with respect to the data sets of the monthly chemical analyses of the descendent mine water, the daily rainfall and the mineral content. The results reveal that the precipitated material undergoes internal self-organization due to interaction of redox, colloid-chemical, microbial, electrical and ripening processes, and not exclusively produced by seasonal fluctuations of material input. Thus, the primary banding of the material, caused by externally forced fluctuations of the redox conditions within the mine water, is reorganized after a short time. The finally observed bands are controlled by non-linear coupling of reaction and transport processes within the mud. A genetic model for the banded mineralization was developed and verified by numerical simulation. 相似文献
994.
研究了GIS技术在城市雨水管网设计中的应用问题,建立了雨水管网设计的相关模型,重点分析了两类直接影响雨水管网工程的计算模型——水力优化计算与指标再优化模型 相似文献
995.
给出了太阳系质心参考系(BRS)和地心参考系(GRS)中的相对论激光测距理论模型,并且利用现有的坐标变换关系证明两种模型在毫米级的精度上是完全等价的。最后指出,由IERS推荐的坐标变换公式与激光测距模型之间存在不自洽性,这种不自恰性对激光测月(LLR)的影响可达约10cm。 相似文献
996.
论RS,GPS与GIS集成的定义、理论与关键技术 总被引:226,自引:6,他引:226
该文从什么是GPS、RS与GIS (简称三S)的集成开头 ,讨论三S集成中需要研究和解决的一些理论与关键技术 ,最后介绍各种可能的集成应用系统 相似文献
997.
998.
999.
鲁西南石炭二叠纪煤系潮坪沉积体系与聚煤作用 总被引:2,自引:0,他引:2
鲁西南石炭二叠纪煤系形成于内陆表海盆地。潮坪沉积体系是研究区聚时重要的沉积体系之一。作者详细研究了潮坪沉积体系的内部构成、成因相及各种沉积体发育特点,分析了沉积组合类型及其成因单元,论述了潮坪沉积体系的聚煤特点及富单元的形成与分布规律。 相似文献
1000.
Li Baosheng Dong Guangrong Zhang Jiasheng Li Sen Jin Heling Chen Huizhong Wen Xiangle Wang Yao Zhu Yizhi 《《地质学报》英文版》1995,8(3):317-328
At least at the beginning of the last glacial epoch, the facies belts of dune sand, sandy loam and loess formed by winds had existed in the Taklimakan desert and areas south of it. There were no appreciable changes in the NE and NW wind systems and their wind forces that deposited dune sand, sandy loam and loess in the global cold stage since the last glacial epoch; accordingly no marked shifts of the boundaries of these aeolian facies belts took place. In the global warm stage since then, the climate in the Taklimakan desert and areas south of it became warm and dry, resulting in ablation of substantial volumes of ice and snow in their surrounding mountains and thus forming alluvial and diluvial deposits in the region. The alluvial-diluvial actions, however, failed to change the general framework of aeolian facies belts. 相似文献