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平安岭小流域是本溪市明山区小流域治理成功的典型。本着"集中治理、连续治理"的原则,采取"瓜藤式"和"珍珠项链式"的治理模式,将生物措施、工程措施和耕作措施结合起来,基本控制了平安岭小流域内人为产生的水土流失,增加了森林覆盖率,减少了水中含沙率,取得了显著的生态效益、经济效益和社会效益。 相似文献
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杨宏波 《水文地质工程地质》1985,(1)
赤水滑坡位于贵州省赤水县城附近的赤水河东岸,属四州盆地南部边缘的山区河谷地带。该滑坡于1982年6月5日连续暴雨的情况下产生了大规模复活滑动,危及了滑坡下化肥厂的安全生产。有关部门决定迅速治理。 滑坡区岩层为侏罗系重庆统遂宁组紫红色泥岩与薄层长石砂岩组成。走向近南北,倾向东,倾角为10°左右。第四系为褐红色粉质轻亚粘土和碎石质亚粘土,厚0.5—15米。 滑坡后壁顶部是一个狭长的斜台地,台面向北倾斜,斜台地的后山坡壁陡峭,是一座海拨400米的山脊,与赤水河漫滩相对高差为160米。滑坡下侧也是一块较 相似文献
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今年以来,登封市积极开展大规模砂矿秩序专项治理集中行动,通过制定完善砂矿准入管理、安全管理、销售管理、税费管理、环境管理和查处违法活动工作制度,建立了砂矿管理长效机制,促进了全市砂矿业健康、有序发展。 相似文献
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国内外地下水污染治理 总被引:2,自引:0,他引:2
美国的富兰克林曾经说过:“井不干,人们是不知道水的价值的”。面对目前世界许多地方的地下水越来越紧缺,以致约20亿人缺少饮用水和农业灌溉用水的现状,开发和保护有效的水资源是非常重要的。然而,例如,美国亚利桑那州的地下水每年“消失”4亿立方米,这是此地自然降雨填充量的两倍 相似文献
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面临矿山开采造成的植被、水文条件被破坏,采、选、冶排放的“三废”及矿毒影响,矿山环境综合治理已刻不容缓。应大力宣传有关法规,依法管理,深入调查,研究解决办法,制定积极治理措施,加速立法,加强环境监理与地质环境监督的协调。 相似文献
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西安市街道灰尘中铬、镉、铅赋存状态及环境效应 总被引:8,自引:0,他引:8
本文通过对街道灰尘中铬、镉、铅三种元素赋存状态研究、铬、铅在街道灰尘中以残渣态为主,镉以有机质结合态为主。虽然铬、铅、镉存在形式稍有差异,但其在街道灰尘中主要以矿物质的形态存在,说明其比较稳定,不易迁移转化,对环境的危害比较持久。在治理措施上应有早遏止微量元素向环境中排放,以免其与灰尘发生相互作用对环境造成长期的危害。 相似文献
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岩石破坏的机理再认识 总被引:1,自引:0,他引:1
岩石的各种强度准则一直是解释岩石或岩体破坏机理的主要理论。此外,从流变现象出发,通过数值模拟、实验对照、理论分析、进一步对岩石破坏机理的解释进行了探讨,认为受力岩石或岩体内差异流动变形也是导致岩石破坏的原因。 相似文献
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建筑工程中的“设计方”一般是指从事工程设计的专业人士,如建筑师和工程师,但也可能包括除施工或供货以外还承担某些工程设计工作的承包商、分包商及供应商。 “设计”并不限于制作建筑及工程图纸或进行结构方面的运算。设计范围极广,甚至包括了某种材料的选用以及为达到某个目的所应采用的工艺。设计的实质就是选择,选择足以满足工程要求 相似文献
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The metamorphic complexes of Tasmania formed during the Cambrian (ca 510 Ma) as a result of rapid compression in a subduction zone setting followed by rapid exhumation, which brought various fault-bounded metamorphic complexes back to the surface in less than 5 Ma. The two highest grade complexes, the Franklin Metamorphic Complex, and the Port Davey Metamorphic Complex, experienced initial growth of metamorphic garnets at ~560°C, ~0.56 GPa. However, their subsequent metamorphic histories diverge, with the FMC displaying a marked increase in pressure (to 1.4 GPa at peak P/T), while the PDMC shows only a slight increase in pressure (to ~0.7 GPa). Both complexes show only a minor increase in temperature (~100°C) between initial garnet growth and peak metamorphic conditions. Rapid exhumation of these complexes can be accounted for by a slab-breakoff model. However, the difference in peak pressure between these complexes requires either continued subduction of the FMC while the PDMC had already begun its return towards the surface or that the subduction zone geometry resulted in significantly different pressures occurring contemporaneously within portions of the channel, which are not far removed from one another. 相似文献
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《Gondwana Research》2001,4(3):307-318
The supracrustal rocks of the Older Metamorphic Group (OMG), consisting of metasediments and ortho-amphibolite, constitute the oldest unit in the Archaean nucleus of Singhbhum. However, there are indications that still older (3.4–3.8 Ga) crust of both sialic and mafic composition existed in this region. The OMG ortho-amphibolites were formed by partial melting of mantle with near chondritic composition ca. 3.3 Ga ago, probably as a result of plume activity. Shortly afterwards, partial melting of the underplated mafic material produced a tonalitic melt (Older Metamorphic Tonalitic Gneiss — OMTG), which intruded the OMG supracrustals and the entire suite was deformed and metamorphosed to upper amphibolite facies. Subsequent to this, melting of the OMG ortho-amphibolites and the lower crustal material of probable andesitic composition produced melts varying in composition from tonalite to granite and these intruded in different phases to produce plutons of Singhbhum Granite, Bonai Granite and Kaptipada Granite, which together form volumetrically the major part of the Archaean nucleus. The older OMG and OMTG occur as enclaves within these younger granitoids. The time difference between the emplacements of the OMTG and the early phases of younger granitic intrusion was of the order of 100–200 Ma. Thus, serial additions of juvenile material led to the formation of a stable microcontinent by 3.2 Ga. Thermally triggered stretching in this microcontinent produced basins peripheral to the present day Singhbhum Granite pluton, and in these basins the younger supracrustal rocks of the Iron Ore Group (IOG), consisting of BIF, associated argillaceous and subordinate arenaceous rocks, and mafic lavas were laid down. There is inadequate field or geochronological evidence to resolve the issue of whether the different iron ore basins were coeval or not. Meagre geochronological data suggest that some of the BIFs are older than ca. 3.1 Ga. Post-IOG activity is confined to the intrusion of mafic dyke swarms and formation of intracratonic basins, the ages of both being uncertain. 相似文献
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层序地层学理论现已日臻完善,位人们往往被局限在大范围、大尺度的研究领域中,包括整个盆地或整个陆架的粗线条描述。那么,小尺度(小范围和次级层序)内的层序格式和沉积样式又是如何的呢?本文将作一阐述。在地层学、沉积学的研究基础上,在区域层序地层学的框架下,将桑塔木断垒带这样一个盆地内的三级局部构造的奥陶系进行层序地层学解剖。由于地震资料分辨率的限制,采用大量的钻井录井资料(岩心、电测等),通过岩性、古生物等特征标志建立相对水深变化曲线,以此来对比划分层序。得出,奥陶系内存在一个Ⅰ类层序界面,并将其划分为两个四级层序及相应的五级层序。其中,高水位体系域为最佳储层带。其研究方法和结论在对其他局部构造的研究中可起到类比作用 相似文献