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The paper presents the evolution of the geographic environment imposed by sea-level changes in selected sites of the Aegean Sea region during the Upper Holocene. The changes are due, mainly, to paroxysmic phases of the actual neotectonic evolution and to differential—in time and space—block movements, and emerged or submerged coasts. The reconstitution of these coasts is presented and, in some cases, natural harbor morphology is revealed. The use and evolution of these sites is discussed. Other sites concern coastal or inland ancient settlements or constructions affected by submersion by the sea, by the rise of the groundwater table, or by uplift movements. A general discussion on engineering measures to be applied for protection of the antiquities affected by these geographic changes closes the presentation. 相似文献
43.
44.
长江口大型桩基码头勘探中的单元体划分问题 总被引:1,自引:0,他引:1
由于桩基持力层的岩性岩相变化十分复杂,应用常规的工程地质单元体划分方法时常出现分现混乱、使用困难等问题,现以第四纪地质研究为基础、以桩基工程评价需要为目的,改进了工作方法,获得较好的工程效果。 相似文献
45.
工程地质评价定量表格化的一种实现方法 总被引:5,自引:0,他引:5
本文对传统的工程地质评价方法作了扩展,称之为工程地质评价的定量表格化。本文详细给出了定量表格化的一种实现方法。两个应用实例表明,该方法既定量又简便,具有良好的适用性和推广前景。 相似文献
46.
五强溪水电站左岸船闸边坡开挖监控设计的理论与实践 总被引:12,自引:7,他引:12
五强溪水电站船闸左岸边坡,是由前震旦系的Pt1(主要为千枚状板岩)和Pt2(主要为砂岩、板岩)组成。因断层穿插,岩体破碎,边坡稳定性很差。为确保边坡在开挖施工期的安全,作者根据工程地质力学和系统科学相结合的方法,对之进行监控设计,取得了成功。 相似文献
47.
风沙动力与风沙工程学当前研究的热点─—主要反映在加深对风沙现象的理解、风沙灾害防治与资源开发三个方面出发,提出了我国在风沙运动力学、土壤风蚀、土地沙漠化的动力机制与过程、风沙地貌形成发育规律、风沙沉积学特征及其形成机制、沙尘暴形成机制以及风沙灾害防护工程技术原理等六个方面的研究建议。 相似文献
48.
岩体水力学概述 总被引:8,自引:0,他引:8
仵彦卿 《地质灾害与环境保护》1995,6(1):57-64
本文通过伙在工程活动与地质环境相互作用分析,揭示了人类工程、岩体与地下水之间的关系;论述了岩体水力学的研究对象,学科地位,研究内容以及研究方法。 相似文献
49.
Kevin Hall 《地球表面变化过程与地形》1987,12(2):137-149
As part of a study on freeze-thaw weathering in the maritime Antarctic an investigation was made of the physical properties of the local rock. Tests were made of point-load compressive strength, Schmidt hammer in situ rock strength, moisture content, indentor resistance and the size range of weathering products. The resulting data were used to consider the form of freeze-thaw weathering operative in the field and its relationship to laboratory simulations. A distinct difference between ‘massive rock’ and ‘intact rock’ is observed in the field. It is suggested that future studies should generate a greater database pertaining to rock properties as it is an invaluable aid in the study of mechanical weathering. 相似文献
50.
Andrew Brookes 《地球表面变化过程与地形》1987,12(4):337-351
Relatively little attention has been given to river channel adjustments that occur downstream from channelization works. This study is concerned with the nature of channel adjustments downstream from a total of 46 channelization works located in low and high energy environments in England and Wales. Channel changes are identified principally by the method of field survey and by reconstructing the original positions of eroded beds and banks. Use is also made of maps, aerial photographs, and engineering drawings of different dates and the technique of space-for-time substitution is applied. Enlargement of channel cross-sections through erosion had occurred downstream from a variety of types, sizes, and dates of channelization works. The maximum increase of channel size was 153 per cent. Out of a total of 14 sites with enlarged channel cross-sections, seven had undergone a change of width only, at a further three width increased rather than depth, and at the remaining four sites depth increases were dominant. These sites all have relatively high stream powers. Factors causing spatial variation of erosion included tree roots locally binding bank sediments and the occurrence of bends. Planform change had taken place at only one site. A further three high stream power sites had downstream reaches incised into bedrock and therefore did not exhibit adjustment. Channel enlargement is explained in terms of increased flood flows downstream from channelization works causing higher stream velocities, which in turn cause erosion, thereby increasing channel width and/or depth. Examination of flow records for 35 stations revealed flood events which would formerly have spread overbank but are now confined by the channelization works and are therefore likely to alter downstream flows. At sites with downstream change it is proposed that the energy of increased flows was sufficient to exceed a threshold required for erosion of perimeter sediments. By contrast the absence of change at a majority of sites in low energy lowland areas could be a reflection of both the incompetence of increased flows to erode and resistance provided by perimeter sediments. Sites with erosion features appear not to have yet attained new equilibrium conditions. 相似文献