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61.
工程物探方法在浅海域地质调查中的应用   总被引:3,自引:0,他引:3  
通过对浅层地震、浅地层剖面、旁侧声纳、海磁等近几年应用较广的物探方法及其工程实例介绍,指出物探方法在浅海域地质调查中的优点及不足。  相似文献   
62.
林玉成 《云南地质》2004,23(4):503-508
煤层气的开发利用是集开发新的高效洁净能源、有利煤矿生产安全、有利大气环保于一身的崭新的绿色工程。本文概略介绍我省煤层气勘探及研究工作进展情况,强调云南丰富的煤层气资源,应是云南的资源优势。  相似文献   
63.
现场快速分析技术及其在地质分析中的应用   总被引:1,自引:0,他引:1  
现场分析是地质科学研究的重要工具。现场分析的内容主要包括野外地球化学分析、船上海洋资源分析、矿山污染监测、生态环境调查等。现场分析的形式大致可分为相对固定的现场实验室、船(车)载移动实验室、便携式仪器或其他小型器械等几种。该文对这三种类型的现场分析进行评述。  相似文献   
64.
数字地质编录中坡面展示影像图的制作研究   总被引:2,自引:0,他引:2  
杨立君  李浩 《现代测绘》2004,27(6):33-35
基于影像的数字地质编录是摄影测量和工程地质学科边缘交叉发展的技术成果之一.目前仍处于研究阶段。介绍了影像数字地质编录中坡面展示影像图的制作原理及其流程,重点阐述了畸变校正后像片坡面影像几何纠正的两种不同的处理方法。实践表明,两种处理方法的结合能够很好地满足数字地质编录中对展示影像图的生成及使用的要求。  相似文献   
65.
从工作实际出发,将测量过程中常用的计算和换算工作,用VisualBasic语言编写成计算程序,最后将各模块集成为一个“测量工具箱”,从而方便了测量工作者处理日常工作中的一些计算和换算问题。  相似文献   
66.
Geography is again becoming an integral part of the premier natural‐science agency of the federal government. Geographic research emphasizes the surface of the earth, a portion of the earth system that the U.S. Geological Survey (USGS) defines as the “critical zone.” Although geography was part of the USGS from the creation of the agency, in recent years geography in the agency has largely been limited to topographic mapping. Recently, the USGS and an advisory committee of the National Research Council (NRC) reviewed the role of geography at the Survey. The committee's report, along with ongoing decision‐making in the federal government, is likely to reshape geography in the USGS. The newly defined USGS has a regional structure and four disciplines: geology, hydrology, biology, and geography. The NRC report emphasizes the need for the creation of a spatial database called the National Map to replace the existing series of paper topographic maps. The report also outlines the need for geographic research in geographic information science (GIScience), nature‐society connections, and bridging of science to decision‐making. The NRC report has been briefed throughout the USGS, in the federal executive branch, and in Congress. The changing role for geography in the USGS requires change in the agency culture, revised budgetary decisions, and the establishment of a long‐term core agenda for research. Academic geographers will need to prepare a new generation of geographers for participation in the USGS and similar agencies.  相似文献   
67.
This paper presents the findings from a study on gravity-induced slope deformations along the northern slope of Mt. Nuria (Rieti-Italy). The slope extends from the village of Pendenza to the San Vittorino plain and hosts the Peschiera River springs, i.e. the most important springs of the Central Apennines (average discharge: about 18 m3/s).

Detailed geological-geomorphological and geomechanical surveys, supported by a site stress-strain monitoring system and laboratory tests, led us to define the main evolutionary features of the studied phenomena. Based on the collected data, a “geological-evolutionary model” was developed with a view to identifying a spatio-temporal correlation between relief forms, jointing of the rock mass and its stress conditions. The geological-evolutionary model was expected to improve numerical simulations and to test our assumptions.

The numerical model also allowed us to simulate changes in the stress-strain conditions of the rock mass and correlate them with jointing, seepage, as well as with site-detected and site-monitored forms and deformations. In particular, significant relations between seepage, tensile stresses within the rock mass, karst solution and collapse of cavities were identified.  相似文献   

68.
地质遗迹旅游的可持续发展   总被引:3,自引:0,他引:3  
高亚峰 《城市地质》2005,17(2):30-33
从介绍地质遗迹及地质遗迹旅游的概念入手,着重就新时期地质遗迹旅游可持续发展的问题,提出了两种思路和相应的策略。  相似文献   
69.
The potential of radar imagery in geological exploration was investigated at a study site in Mauritania (Akjoujt region). Compared with optical images, the results obtained show how radar imagery can help not only in detecting surface geological structures such as dykes and veins, but also mapping subsurface structures beneath a shallow layer of sand (palaeochannels). The mapping potential was found to be much better at long wavelengths than at short ones (L-band, compared with C- and X-band). As for optical images, their contribution is much more limited in the mapping of surface geological structures, and inappropriate for detecting subsurface structures. We conclude that spatial remote sensing enables the improvement of existing geological maps and the optimization of cartographic surveying. To cite this article: N. Baghdadi et al., C. R. Geoscience 337 (2005).  相似文献   
70.
Uncertainty is ubiquitous in geology, and efforts to characterise and communicate it are becoming increasingly important. Recent studies have quantified differences between perturbed geological models to gain insight into uncertainty. We build on this approach by quantifying differences in topology, a property that describes geological relationships in a model, introducing the concept of topological uncertainty. Data defining implicit geological models were perturbed to simulate data uncertainties, and the amount of topological variation in the resulting model suite measured to provide probabilistic assessments of specific topological hypotheses, sources of topological uncertainty and the classification of possible model realisations based on their topology. Overall, topology was found to be highly sensitive to small variations in model construction parameters in realistic models, with almost all of the several thousand realisations defining distinct topologies. In particular, uncertainty related to faults and unconformities was found to have profound topological implications. Finally, possible uses of topology as a geodiversity metric and validation filter are discussed, and methods of incorporating topological uncertainty into physical models are suggested.  相似文献   
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