云南省乡镇农村地震灾害直接经济损失研究

根据1993-2003年30余次云南省地震的损失评估调查资料,建立了云南省农村乡镇各烈度区房屋建筑物损失与受灾人口的定量关系,初步建立了各烈度区水利设施损失、生命线工程损失与房屋建筑物损失的关系。以云南地区2004年-2005年4次地震为实例,用以上计算方法估算了4次地震的直接经济损失,并与地震现场评估的结果作比较,结果表明,该计算模型实用性强,对一般性地震的模拟误差平均值在30％左右。     

江西某高填方路基病害多阶段注浆加固工程实录

因水的浸泡作用及未清基导致江西某高填方路基产生病害,笔者用边坡多阶段注浆方法对其整治,设计及施工实践证明边坡多阶段注浆加固模型是正确的,也是适用的.多阶段注浆具有工期短、速度快,可以边施工边使用,既经济又稳妥,不改变已建成的道路外貌,能最大限度减少各方经济损失;多阶段注浆法及其加固模型可以在工程中使用.     

矿山人均保有储量:我国金属矿山合理经济开发的一个标量

文章分析对比了我国国有及非国有规模以上矿山企业的主要经济指标,认为矿业开发要走可持续发展的途径,促进矿产资源的充分、合理、有效开发,实现满足市场需求、兼顾环境保护和社会稳定的目标,就必须积极探索和慎重考虑矿山企业从业人数的合理控制问题;依据胶东大型金矿山实际资料的初步分析,明确提出"矿山人均保有储量"是制约矿山合理开发和矿业可持续发展的重要指标;矿山人均储量的合理配置和适度调控问题不仅值得进一步研究,而且应该引起有关部门的广泛注意和高度重视.     

遥感影像分析在新增建设用地督察中的应用

以卫星影像大数据和时空数据挖掘技术为基础,采用深度学习框架支撑,构建了面向新增建设用地遥感监测应用需求的深度学习训练平台,可智能发现自然资源督察线索,全面提高自然资源督察问题的发现能力.该技术可广泛服务于大范围、高频次的督察工作,为督察工作提供更及时客观全面的信息基础和保障.     

公路隧道围岩地质条件评价方法及其富溪隧道应用研究

为了达到快速、准确、可靠的围岩分类,有效指导隧道施工,在充分研究和吸取国内外有关围岩分类的经验和成果基础上,针对隧道施工期间的围岩类别鉴定方法,提出了一种可用于隧道施工期间围岩类别鉴定的快速分类方法,该方法以定量与定性相结合、多专家评分的方式在开挖掌子面现场进行观察、量测及评价,无需复杂试验或测量以及繁杂计算,可迅速得出评价结果。为了更加全面地反映隧道围岩情况,准确评价围岩工程性质,结合目前国际上流行的Q分类系统,在富溪隧道第一手实测资料的基础上,根据快速分类结果和Q指标分类结果对富溪隧道围岩条件进行综合评价,为其隧道施工提供了合理的支护参数。     

收缩城市建设用地利用效率时空分异及影响机制——以黑龙江省伊春市为例

建设用地是城镇经济社会活动的空间载体,其利用效率是调控建设用地扩张和配置的重要基础.论文以收缩型城市——黑龙江省伊春市为例,利用DEA模型测算了1995-2015年伊春市建设用地利用效率分析其时空演变规律,并运用地理探测器模型探究伊春市建设用地利用效率空间分异的影响机制,结论如下:①1995-2015年伊春市建设用地利...     

Engineering characteristics and uses of duricrusts in Australia

The uses and shortcomings of duricrusts (ferricrete, calcrete and silcrete) in engineering construction (as used for road‐base, aggregate, foundation materials and aquifers) are reviewed. Australian production of these materials represents about one‐third of all unprocessed road‐base and they are especially important as pavement courses for lightly trafficked, low‐cost rural and outback roads. However, duricrusts are regarded as marginal materials at best because of their typically poor grading, particle unsoundness, high fines plasticity, and absorption of water and bitumen. These materials are used because they are available locally in areas that are otherwise lacking in hard rock materials, such as deeply weathered and sedimentary rock terrains. The weathering profiles of which they form part are characterized by high permeability (despite being clay‐rich), variable cementation, low compressibility and a tendency to become weaker with depth. Although the more indurated layers are unrippable, they are also difficult to blast. Pedogenic (nodular) duricrusts were formerly sought for natural road‐base, because they occur widely and require only rudimentary processing. However, well‐cemented groundwater (vadose) duricrusts are now the preferred deposits, even though they require crushing and screening. Ferricrete is the most widely exploited of the duricrusts for engineering purposes, especially in northern and southwestern Australia, although calcrete is important in South Australia and in the Murray Basin. Silcrete is only a minor source of aggregate and road‐base, mainly in western Queensland.     

Silurian and Devonian systems

The Ediacara mineral field is situated 30 km W of Beltana on the western margins of the Flinders Ranges, South Australia, and consists of silver‐lead and copper deposits in lower Cambrian carbonate rocks that contain anomalous base‐metal contents throughout the Adelaide Geosyncline. The lower Cambrian rocks, which consist of the basal Parachilna Formation and overlying Ajax Limestone, rest disconformably on the Precambrian, and at Ediacara occupy a shallow N‐S elongate syncline near the hinge zone of the Adelaide Geosyncline. The main primary ore minerals of the silver‐lead mineralization are galena and pyrite, with very minor chalcopyrite and sphalerite, and rare tetrahedrite and pearceite. The gangue consists mainly of silica (both chalcedony and quartz), with minor dolomite and rare barite. The mineralization is stratabound and occurs in conformable zones, the lowest of which commences about 30–50 m above the base of the Cambrian sequence. The host to the silver‐lead mineralization, the Ajax Limestone, can be subdivided into three units which represent a set of lithologies, structures and organic traces indicative of a shallow near‐shore carbonate environment. The silver‐lead mineralization is mainly present in sandy and laminated dolomites which were deposited in an environment ranging from sub‐tidal to bar and channel and tidal flat, respectively. Four types of mineralization have been recognized; disseminated sulphides of syngenetic and/or diagenetic origin and epigenetic concentrations along stylolites, in veins and as breccia fillings. Post‐depositional solution activity has affected a large proportion of the carbonate sequence. The effects of this activity range from stylolites through stylobreccias to solution collapse breccias. The epigenetic concentrations of mineralizations have apparently been formed by the remobilization of the disseminated sulphides during solution activity. The ore and gangue minerals of the epigenetic mineralization display both euhedral forms and distinct colloform banding, and framboidal textures have also been observed in both pyrite and galena. There is evidence of repeated episodic precipitation and no simple paragenetic sequence can be recognized. Fluid inclusions in silica and dolomite associated with the epigenetic mineralization have homogenization temperatures of 159 to 199°C and freezing temperatures that indicate the fluids to be saline brines containing NaCl with CaCl₂ and/or MgCl₂. Sulphur isotope analyses show a range of 8³⁴S values from ‐12.5 to +8.6 per mil, with no evidence of significant differences between the four types of mineralization. The data suggest deposition of the disseminated sulphides as a result of biological reduction of seawater sulphate in a system partially open with respect to sulphate supply. Subsequent remobilization of sulphides apparently involved little or no sulphur isotope fractionation. The Ediacara silver‐lead deposits have many features in common with Mississippi Valley‐type lead‐zinc deposits and appear to have similarities in terms of genesis, in that the epigenetic mineralization has been formed as a result of post‐depositional solution activity during diagenesis in a sedimentary basin. The scale of transport of the metals deposited as the epigenetic mineralization at Ediacara appears, however, to have been very much less than that of the metals in other Mississippi Valley‐type deposits.     

Historical development of the saltmarsh at Wells,Maine

Comparisons of maps and aerial photographs dating from the late 1700s to the present document the recent development of an 8 km² saltmarsh that is situated behind a barrier spit in southern Maine. Tidal channels that were relatively narrow in 1794 became wider by 1872. The reduction of marsh bordering tidal channels is interpreted as evidence that marsh accretion could not keep pace with rising sea-level. This suggests that the rate of sea-level rise had increased, although a change in discharge or sediment load caused by extensive settlement and land clearance may also have been involved. Meander patterns of the tidal streams changed considerably throughout the time period covered by the maps, demonstrating that the streams of this marsh are more dynamic than some others that have been widely reported in the literature. These differences in stream dynamics are probably related to the differences in sedimentological structure of the marshes. Between 1872 and 1956 the barrier spit eroded on its inside (shoreward) edge, probably in response to the construction of riprapping and houses along the spit, and the subsequent reduction of overwash and aeolian transport of sediment. Modification of the tidal inlet and adjacent marsh during the 1960s, including jetty construction, dredging, and filling of portions of the marsh surface, affected the marsh only locally. One tidal stream has been migrating rapidly apparently in response to compaction of peat by dredge spoils and consequent local disruption of the marsh hydrology. Except for this migration, erosion of the marsh edge occurred immediately after the inlet modifications; planimetric changes in the marsh and its streams have been minor since then.     

长江三峡地区经济开发条件分析

长江三峡地区区域地理位置重要，区位优势明显，开发意义重大；区内农业、水能、矿产和旅游等优势自然资源丰富，组合配置良好，开发潜力巨大；区域经济开发的交通、能源、出入通道等基础条件已基本具备。