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121.
利用测井曲线绘制煤岩层真厚对比图 总被引:2,自引:0,他引:2
采用三次样条函数拟合测井数据,并使用新的采样间隔对其进行采样,将采样数据映射到真厚的钻孔柱状图上,从而绘制出真厚对比图。实际编程中,为保证其拟合精度及计算效率,实际采用的计算步长一般为本层厚度加上下扩展10m。选择采样间隔时,可对测井曲线进行抽稀,以减小数据占用的空间。该方法的使用解决了长期以来地质与测井对比图工作分离、结论出现差异的问题。 相似文献
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123.
简要回顾了数字地震学诞生以来所取得的科学成果。结合我国地震观测系统大规模数字化改造的实践,着重阐述了区域数字化地震台网的观测优势,以及在台网建设目标、观测资料的充分利用和高素质人才培养方面存在的劣势和不足。还提出了对关于区域数字地震台网建设和发展过程中的指导思想、“软件”和“硬件”的关系、基础和应用研究与地震预报的关系、数字地震学的发展与高素质人才培养的关系等等问题的思考和建议。 相似文献
124.
Landform‐oriented flow‐routing algorithm for the dual‐structure loess terrain based on digital elevation models
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The loess landform in the Loess Plateau of China is with typical dual structure, namely, the upper smooth positive terrain and the lower cliffy negative terrain (P–N terrain for short). Obvious differences in their morphological feature, geomorphological mechanism, and hydrological process could be found in the both areas. Based on the differences, a flow‐routing algorithm that separately addresses the dual‐structure terrain would be necessary to encompass this spatial variation in their hydrological behaviour. This paper proposes a mixed flow‐routing algorithm to address aforementioned problems. First, the loess landform surface is divided into P–N terrains based on digital elevation models. Then, specific catchment area is calculated with the new algorithm to simulate the water flows in both positive and negative terrain areas. The mixed algorithm consists of the multiple flow‐routing algorithm (multiple‐flow direction) for positive areas and the D8 algorithm for negative areas, respectively. The approach is validated in two typical geomorphologic areas with low hills and dense gullies in the northern Shaanxi Loess Plateau. Four indices are used to examine the results, which show that the new algorithm is more suitable for loess terrain in simulating the spatial distribution of water accumulation, as well as in modeling the flow characteristics of the true surface by considering the morphological structures of the terrain. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
125.
C. J. Hapke 《地球表面变化过程与地形》2005,30(6):679-697
High‐resolution historical (1942) and recent (1994) digital terrain models were derived from aerial photographs along the Big Sur coastline in central California to measure the long‐term volume of material that enters the nearshore environment. During the 52‐year measurement time period, an average of 21 000 ± 3100 m3 km?1 a?1 of material was eroded from nine study sections distributed along the coast, with a low yield of 1000 ± 240 m3 km?1 a?1 and a high of 46 700 ± 7300 m3 km?1 a?1. The results compare well with known volumes from several deep‐seated landslides in the area and suggest that the processes by which material is delivered to the coast are episodic in nature. In addition, a number of parameters are investigated to determine what influences the substantial variation in yield along the coast. It is found that the magnitude of regional coastal landslide sediment yield is primarily related to the physical strength of the slope‐forming material. Coastal Highway 1 runs along the lower portion of the slope along this stretch of coastline, and winter storms frequently damage the highway. The California Department of Transportation is responsible for maintaining this scenic highway while minimizing the impacts to the coastal ecosystems that are part of the Monterey Bay National Marine Sanctuary. This study provides environmental managers with critical background data on the volumes of material that historically enter the nearshore from landslides, as well as demonstrating the application of deriving historical digital terrain data to model landscape evolution. Published in 2005 by John Wiley & Sons, Ltd. 相似文献
126.
N. V. Trifonov 《Seismic Instruments》2009,45(1):83-85
On the basis of an analysis of the development history of seismometers, the conclusion is made that a new generation of instruments—digital seismometers—should be created. The functions of a digital seismometer and its advantages over other existing instruments are described in brief. 相似文献
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128.
西宁地震台FHD数字化核旋仪从2006年10月安装以来,一直与模拟仪器并行工作。二者采样率不同,所测的量也不相同。在对西宁地震台磁变仪的记录图纸进行数字化转换、生成分钟值的基础上,对FHD仪和磁变仪的观测结果进行对比分析。结果表明:数字FHD仪比三分量磁变仪更加准确地记录了当地地磁场的变化,数字仪器的观测资料明显优于模拟仪器。 相似文献
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130.
截齿截割煤体变形破坏过程的散斑测试研究 总被引:1,自引:0,他引:1
采用白光数字散斑相关测定方法,在压力机上,在截割模拟实验台上分别对煤试件进行刀齿、镐齿的截割实验,研究被截割煤体的变形破坏过程。研究表明:截齿截割煤体过程中,煤体出现稳定的变形局部化带,且最终发展为宏观裂纹;煤体变形局部化带为一个倾斜带;刀齿截割时,变形局部化发展较慢,但产生变形局部化后,局部化带宽且带内应变值较高;而镐齿截割时,变形局部化发展较快,但产生局部化后,局部化带窄且带内应变值不如刀齿高。截齿截割作用下的煤体变形破坏主要是剪破坏。 相似文献