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121.
青鹏煤矿位于重庆市沙坪坝区青木关镇及壁山县壁城镇,已开采50余年.随着开采水平的延深,矿井地下水流场发生了相应的变化,改变了地下水原有的补、径、排条件.2012年2月,青鹏煤矿-200m水平-22103运输巷施工过程中,碛头煤层(M2)顶板裂隙突水造成局部淹井事故.通过地面及井下水文地质调查以及采取地表水、泉水、矿井水样进行水质分析,指出矿井突水水源由须家河组裂隙水、采空区积水和嘉陵江组灰岩岩溶裂隙水的越流补给3部分组成.为矿井防治水提供了水文地质依据. 相似文献
122.
123.
全国资源与生态环境遥感监测数据管理与应用服务系统设计 总被引:2,自引:0,他引:2
为推动资源与生态环境遥感监测数据的应用与服务,为国家、相关行业管理决策和社会公众提供有价值的信息,需要在资源与生态环境遥感监测成果数据基础上,开发数据管理与应用服务系统。本文从国家资源与生态环境建设的实际需求出发,结合国土资源部实施的环北京地区资源与生态环境遥感监测成果,探讨资源与生态环境遥感监测数据管理与应用服务的技术解决方案,搭建资源与生态环境遥感监测数据管理与应用服务技术平台,并实现网络环境下对资源与生态环境监测形成的各种类型数据的集成化管理。 相似文献
124.
利用长江中下游、河口及口外、浙-闽沿岸陆架6个主要沉积盆地的40个晚第四纪钻孔及其年代学数据和长江口外、陆架的浅地层剖面,计算了全新世不同阶段各沉积盆地的沉积速率,并进行了近7 000年来泥沙堆积通量的估算。研究发现全新世早期距今10 000年至8 000年间长江口下切古河谷是长江泥沙的主要堆积中心,沉积速率可高达15m/ka。随着海平面上升,全新世中期长江中下游也成为长江泥沙的重要沉积盆地,其中江汉盆地的沉积速率可达10m/ka。近2 000年来,口外、陆架的堆积呈明显增加趋势,反映长江中下游盆地和河口可容空间日益减小。根据沉积速率估算,距今7 000年来长江中下游堆积泥沙约13 074×108 t,同期水下三角洲和陆架的泥沙堆积量约为9 470×108 t。研究还发现全新世以来有两个异常低沉积速率时期:距今8000-7 000年期间上述各沉积盆地沉积速率均显著低,未见长江泥沙的沉积中心; 距今4 000-2 000 年期间长江口呈现低沉积速率。 这两次异常的原因推测与海平面、气候波动事件密切相关。 相似文献
125.
Hani N. Khoury 《Arabian Journal of Geosciences》2018,11(4):72
The Azraq basin (the Badia region in NE-Jordan) is rich in its industrial rocks and minerals. Most of the commodities are concentrated in one area, which is the Azraq depression (El-Qa’). The climatic changes (wet and dry) of Azraq closed lake contributed in the formation of industrial rocks and minerals in the El-Qa’. Basalt, pyroclastics, zeolites, diatomaceous earth, bentonite, palgorskite, porcelanite, saline brines, chalk, limestone, and gypsum are the potential industrial commodities. The basaltic rocks are of high alkalis content and good homogeneity and are of good potential use in constructions and cast basalt. The scoriaceous pyroclastic material proved to be of excellent properties for use as lightweight aggregates, cultivation purposes, and for the production of pozzolanic cement. Smectite-rich beds (bentonite) from Ein El Badia could be used as binder, absorbent, and additives for feeding farm animals. Palygorskite is potential for use in drilling mud, paint, pharmaceuticals, and as a filtering medium. The diatomaceous earth deposits are Moler type and could be used as filter aid and absorbent. Zeolites are efficient for agricultural purposes, animal waste, and wastewater treatment plants. Saline brine is exploited in the Azraq mudflat area for table salt. Porcelanite could be used as an absorbent of hazardous elements, abrasive, and filler. The softness and high purity of chalk enable its use as filler and in the lime production. The large limestone concretions are of high quality for use as a building stone. Gypsum (gypcrete) could be used after the removal of the undesired chert impurities. The Badia region is a highly potential area for future exploration and mining industry in a manner that achieves the required outcomes and minimizes impacts on ecosystems. 相似文献
126.
Kazutaka Yamaoka Yoshihiro Ueda Hajime Inoue Fumiaki Nagase Ken Ebisawa Taro Kotani Yasuo Tanaka 《Astrophysics and Space Science》2001,276(1):19-22
We summarize the ASCA observations of the two Galactic superluminal sources GRO J1655–40 and GRS 1915+105, focusing on theabsorption line features.The high spectroscopic capability of ASCA enabled us to detectiron-K absorption line features from both objects. This is direct evidence for the presence of highly ionized plasma in a non-spherical configuration around a black hole, and is considered to be a unique signature of superluminal jet systems. The candidate of the line-absorber would be a part of an accretion disk at a distance of 109-11 cm from the central X-ray source. 相似文献
127.
Brillouin light scattering technique can be successfully used to determine the whole set of elastic and piezoelectric constants of a ZnO single crystal irradiated by different laser energy densities, into a micron range (radiation layer thickness). It is found that the scattering intensity, the linewidth and the Brillouin scattering shift of acoustic phonons are all strongly dependent on laser energy density. Based on the sound propagation equations and these results, the directional dependences of the compressional and shear moduli of the irradiated ZnO sample in the (001) plane are investigated. It is found that under an appropriate laser condition, 248 nm KrF excimer laser irradiation can significantly improve the surface quality and increase the elastic properties of ZnO single crystal. This procedure has potential applications in the fabrication of ZnO-based surface acoustic wave and optic-electronic devices. 相似文献
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129.
Analyses of 72 samples from Upper Panjhara basin in the northern part of Deccan Plateau, India, indicate that geochemical
incongruity of groundwater is largely a function of mineral composition of the basaltic lithology. Higher proportion of alkaline
earth elements to total cations and HCO3>Cl + SO4 reflect weathering of primary silicates as chief source of ions. Inputs of Cl, SO4, and NO3 are related to rainfall and localized anthropogenic factors. Groundwater from recharge area representing Ca + Mg–HCO3 type progressively evolves to Ca + Na–HCO3 and Na–Ca–HCO3 class along flow direction replicates the role of cation exchange and precipitation processes. While the post-monsoon chemistry
is controlled by silicate mineral dissolution + cation exchange reactions, pre-monsoon variability is attributable chiefly
to precipitation reactions + anthropogenic factors. Positive correlations between Mg vs HCO3 and Ca + Mg vs HCO3 supports selective dissolution of olivine and pyroxene as dominant process in post-monsoon followed by dissolution of plagioclase
feldspar and secondary carbonates. The pre-monsoon data however, points toward the dissolution of plagioclase and precipitation
of CaCO3 supported by improved correlation coefficients between Na + Ca vs HCO3 and negative correlation of Ca vs HCO3, respectively. It is proposed that the eccentricity in the composition of groundwater from the Panjhara basin is a function
of selective dissolution of olivine > pyroxene followed by plagioclase feldspar.
The data suggest siallitization (L < R and R
k) as dominant mechanism of chemical weathering of basalts, stimulating monosiallitic (kaolinite) and bisiallitic (montmorillonite)
products. The chemical denudation rates for Panjhara basin worked out separately for the ground and surface water component
range from 6.98 to 36.65 tons/km2/yr, respectively. The values of the CO2 consumption rates range between 0.18 × 106 mol//km2/yr (groundwater) and 0.9 × 106 mol/km2/yr (surface water), which indicates that the groundwater forms a considerable fraction of CO2 consumption, an inference, that is, not taken into contemplation in most of the studies. 相似文献
130.