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971.
Evaluation of shallow geothermal energy resources in the Beijing-Tianjin-Hebei Plain based on land use
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To discover the characteristics, distribution and potential of shallow geothermal energy in the Beijing-Tianjin-Hebei Plain area. This paper, based on a large amount of data collection and field investigations, evaluateed the shallow-layer geothermal energy in the study area through the analytic hierarchy process and comprehensive index method. Based on suitability zoning results superimposed with 1:100 000 land use data, the study area is divided into encouraged, controlled, restricted and prospective mining areas regarding the development of shallow geothermal energy, and the economic availability of shallow geothermal energy in the encouraged and controlled areas are evaluated. The results show that the shallow geothermal energy in the Beijing-Tianjin-Hebei Plain can meet the heating and cooling demand of 6×108 m~2 of buildings, equivalent to 1.15×10~7 t of standard coal, thus reducing carbon dioxide emissions by 2.73×10~7 t and reducing sulfur dioxide emissions by 1.95×10~5 t. According to the development and utilization mode, the energy demand level and the Beijing-Tianjin-Hebei coordinated development plan, the development and utilization of geothermal resources in the plain area has two types: Urban concentrated mining areas and rural scattered mining areas. The scale and level of intensive utilization of regional geothermal resources are of great significance. 相似文献
972.
基于GIS的小江断裂中北段滑坡灾害危险性评价 总被引:1,自引:0,他引:1
小江断裂中北段作为金沙江下游重大水电工程库区内最重要的活动断裂构造,其沿线滑坡地质灾害发育,严重制约了当地的经济和社会发展。在详细调查了小江断裂中北段沿线滑坡地质灾害的基础上,选取了坡度、坡向、工程地质岩组、岸坡结构、断裂构造等9个影响因子作为评价指标,对研究区滑坡灾害的发育分布规律进行了分析研究,并采用AHP-CF法建立了滑坡灾害危险性评价模型,利用GIS空间分析功能得出了研究区滑坡地质灾害危险性分区。通过检验曲线验证滑坡地质危险性评价结果可知,AUC值为80%。 相似文献
973.
974.
Many informal communities within urban areas in sub-Saharan Africa are heavily reliant on shallow hand-dug wells for water, but these are vulnerable to contamination from a range of sources. This paper assesses the heavy metal contamination and total coliform risk of unprotected shallow wells in Ndola, Zambia – a city struggling with contaminated surface waters from both bacteriological and potential mining waste products. One hundred and twenty three shallow wells were sampled across the Ndola, and these encompassed the three main lithologies of the city. All wells lacked an internal casing, however, some wells did have covers and/or pavements surrounding the wells, albeit of dubious efficacy. Despite the lack of protection, the quality of water used abstracted from these wells generally met the World Health (WHO) guidelines for heavy metals (with the exception of Al) and total coliforms (although, this was highly variable). The quality of shallow well water varied across Ndola relative to the underlying geology, where total recoverable concentrations were typically lowest in granite-gneiss. Dissolved load concentrations were lowest in dolomite-limestone, highlighting the role of aquifer geology in acting as a buffer against metal toxicity. Our study illustrates that shallow wells, within the appropriate geological units, may provide a safe and reliable source of drinking water. Well protection is, however, needed to ensure that the proliferation of shallow well use does not lead to regional degradation of the groundwater resource. There is an immediate need to invest in promoting internal well casing during the construction of shallow wells, concomitant with investment and education into protecting wells at the surface, despite the current relatively low level of contamination in wells without protection. 相似文献
975.
In order to generate well-based design decisions on reinforcement of landslide slopes and road embankment slopes, a system of combined geotechnical analysis of geological conditions is suggested which includes topographic and geophysical survey, and laboratory studies of soils using infra-red spectroscopy methods. Calculations of slopes' deflected modes are carried out with taking into account elastic and elasto-plastic behavior of soil, and the presence of supporting man-made constructions. Results of the application of the system suggested may be used as criteria for the classification of landslide slopes along permanent ways according to the degree of danger when used for transportation. 相似文献
976.
A comparison of the sedimentary records of the 1960 and 2010 great Chilean earthquakes in 17 lakes: Implications for quantitative lacustrine palaeoseismology
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Maarten Van Daele Jasper Moernaut Lindsey Doom Evelien Boes Karen Fontijn Katrien Heirman Willem Vandoorne Dierk Hebbeln Mario Pino Roberto Urrutia Robert Brümmer Marc De Batist 《Sedimentology》2015,62(5):1466-1496
Seismically‐induced event deposits embedded in the sedimentary infill of lacustrine basins are highly useful for palaeoseismic reconstructions. Recent, well‐documented, great megathrust earthquakes provide an ideal opportunity to calibrate seismically‐induced event deposits for lakes with different characteristics and located in different settings. This study used 107 short sediment cores to investigate the sedimentary impact of the 1960 Mw 9·5 Valdivia and the 2010 Mw 8·8 Maule earthquakes in 17 lakes in South‐Central Chile (i.e. lakes Negra, Lo Encañado, Aculeo, Vichuquén, Laja, Villarrica, Calafquén, Pullinque, Pellaifa, Panguipulli, Neltume, Riñihue, Ranco, Maihue, Puyehue, Rupanco and Llanquihue). A combination of image analysis, magnetic susceptibility and grain‐size analysis allows identification of five types of seismically‐induced event deposits: (i) mass‐transport deposits; (ii) in situ deformations; (iii) lacustrine turbidites with a composition similar to the hemipelagic background sediments (lacustrine turbidites type 1); (iv) lacustrine turbidites with a composition different from the background sediments (lacustrine turbidites type 2) and (v) megaturbidites. These seismically‐induced event deposits were compared to local seismic intensities of the causative earthquakes, eyewitness reports, post‐earthquake observations, and vegetation and geomorphology of the catchment and the lake. Megaturbidites occur where lake seiches took place. Lacustrine turbidites type 2 can be the result of: (i) local near‐shore mass wasting; (ii) delta collapse; (iii) onshore landslides; (iv) debris flows or mudflows; or (v) fluvial reworking of landslide debris. On the contrary, lacustrine turbidites type 1 are the result of shallow mass wasting on sublacustrine slopes covered by hemipelagic sediments. Due to their more constrained origin, lacustrine turbidites type 1 are the most reliable type of seismically‐induced event deposits in quantitative palaeoseismology, because they are almost exclusively triggered by earthquake shaking. Moreover, they most sensitively record varying seismic shaking intensities. The number of lacustrine turbidites type 1 linearly increases with increasing seismic intensity, starting with no lacustrine turbidites type 1 at intensities between V½ and VI and reaching 100% when intensities are higher than VII½. Combining different types of seismically‐induced event deposits allows the reconstruction of the complete impact of an earthquake. 相似文献
977.
978.
《International Journal of Digital Earth》2013,6(8):688-708
In this paper, GIS-based ordered weighted averaging (OWA) is applied to landslide susceptibility mapping (LSM) for the Urmia Lake Basin in northwest Iran. Nine landslide causal factors were used, whereby the respective parameters were extracted from an associated spatial database. These factors were evaluated, and then the respective factor weight and class weight were assigned to each of the associated factors using analytic hierarchy process (AHP). A landslide susceptibility map was produced based on OWA multicriteria decision analysis. In order to validate the result, the outcome of the OWA method was qualitatively evaluated based on an existing inventory of known landslides. Correspondingly, an uncertainty analysis was carried out using the Dempster–Shafer theory. Based on the results, very strong support was determined for the high susceptibility category of the landslide susceptibility map, while strong support was received for the areas with moderate susceptibility. In this paper, we discuss in which respect these results are useful for an improved understanding of the effectiveness of OWA in LSM, and how the landslide prediction map can be used for spatial planning tasks and for the mitigation of future hazards in the study area. 相似文献
979.
The main objective of this work is to establish the applicability of shallow surface‐seismic traveltime tomography in basalt‐covered areas. A densely sampled ~1300‐m long surface seismic profile, acquired as part of the SeiFaBa project in 2003 ( Japsen et al. 2006 ) at Glyvursnes in the Faroe Islands, served as the basis to evaluate the performance of the tomographic method in basalt‐covered areas. The profile is centred at a ~700‐m deep well. VP, VS and density logs, a zero‐offset VSP, downhole‐geophone recordings and geological mapping in the area provided good means of control. The inversion was performed with facilities of the Wide Angle Reflection/Refraction Profiling program package ( Ditmar et al. 1999 ). We tested many inversion sequences while varying the inversion parameters. Modelled traveltimes were verified by full‐waveform modelling. Typically an inversion sequence consists in several iterations that proceed until a satisfactory solution is reached. However, in the present case with high velocity contrasts in the subsurface we obtained the best result with two iterations: first obtaining a smooth starting model with small traveltime residuals by inverting with a high smoothing constraint and then inverting with the lowest possible smoothing constraint to allow the inversion to have the full benefit of the traveltime residuals. The tomogram gives usable velocity information for the near‐surface geology in the area but fails to reproduce the expected velocity distribution of the layered basalt flows. Based on the analysis of the tomogram and geological mapping in the area, a model was defined that correctly models first arrivals from both surface seismic data and downhole‐geophone data. 相似文献
980.