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Xunjian X.,Bureau of Geological Exploration of Chongqing | Qiang Y.,Center for Hydrogeology and Environmental Geology
Proceedings - 2014 5th International Conference on Intelligent Systems Design and Engineering Applications, ISDEA 2014

A large number of accumulation landslides induced by water storage in the Three Gorges reservoir, after the landslide danger happening, its stability evolutionary trend is the focus of the research, which have important sense to landslides prevention and control. This paper selects two of the accumulation landslides which has different structure, Qingshi landslide and Huanglianshu landslide, as the research object. Based on the major deformation area of the landslide changes with reservoir water fluctuation, analyzes on the soil accumulation landslides and rock accumulation landslide stability evolutionary trend was made. It is concluded that major deformation of rock mass accumulation landslide area is not affected by reservoir water fluctuation, while soil accumulation landslide response positively during the first reservoir water fluctuation process, the deformation of the disintegration region is significantly higher than the overall regional. Accumulation landslide reaches a new equilibrium after hydrology 1-2 years, and the stability to give priority to with rainfall influence. © 2014 IEEE. Source

Based on the research of interlayer-gliding structures in Panbei and Panji No.1 coal mine that are located in the each wing of Panji anticline, the Panji mining area is divided into 9 main interlayer-gliding areas and 29 sub-regions. The results indicate that the interlayer-gliding structures mainly developed in the anticline wings, which show obvious symmetry at the type and distribution. The types of the interlayer-gliding structures are fault-sliding and corrugation type in the wings and fracture type in the core area. The type and manifestation of the interlayer-gliding structures also show symmetry in the similar depth. From up to down, the interlayer-gliding type show obvious regularity that fracture type is mainly developed in the shallow area, down is fault-sliding type and corrugation type is mainly developed in the deep or the interchange of the faults. Take fuzzy comprehensive evaluation method to evaluate the inter-gliding structure in west area of Panji No.1 coal mine. The results showed that the results from using fuzzy comprehensive assessment were similar with the results exposed by coal mine. Good effects were obtained for predicting the development intensity of the seam-gliding structure in deep unmined areas in combination with geological conditions of coal mine, providing references for production arrangement of coal mine. © (2012) Trans Tech Publications, Switzerland. Source

Yao Y.,Peking University | Zheng C.,Peking University | Zheng C.,University of Alabama | Liu J.,Peking University | And 4 more authors.
Hydrological Processes

The Heihe River Basin (HRB) is an inland watershed in northwest China with a total area of approximately 130,000 km2, stretching from the Qilian Mountains in the south to the oases and agricultural fields in the middle and further to the Gobi desert in the north bordering Mongolia. As part of a major ecohydrological research initiative to provide a stronger scientific underpinning for sustainable water management in arid ecosystems, a regional-scale integrated ecological and hydrological model is being developed, incorporating the knowledge based on the results of environmental isotope tracer analysis and the multiscale observation datasets. The first step in the model development effort is to construct and calibrate a groundwater flow model for the middle and lower HRB where the oases and vegetation along the Heihe river corridor are highly dependent on groundwater. In this study, the software tool 'Arc Hydro Groundwater' is used to build and visualize a hydrogeological data model for the HRB that links all relevant spatiotemporal hydrogeological data in a unified geodatabase within the ArcGIS environment. From the conceptual model, a regional-scale groundwater flow model has been developed using MODFLOW-2005. Critical considerations in developing the flow model include the representation of mountainous terrains and fluvial valleys by individual model layers, treatment of aquifer heterogeneities across multiple scales and selection of proper observation data and boundary conditions for model calibration. This paper discusses these issues in the context of the Heihe River Basin, but the results and insights from this study will have important implications for other large, regional groundwater modelling studies, especially in arid and semiarid inland river basins. © 2014 John Wiley & Sons, Ltd. Source

Zhang M.N.,Hubei University | Han S.B.,Center for Hydrogeology and Environmental Geology | Li X.F.,Center for Hydrogeology and Environmental Geology
2010 2nd Conference on Environmental Science and Information Application Technology, ESIAT 2010

Yinchuan Plain is one of drinking-water endemic fluorosis areas in China. To the west of the Yellow River\ phreatic water with high fluorine distributes in alluvial lacustrine plain and confined water only distributes in Dawukou region to the northwest of Helan Mountain. To the east of the Yellow River high fluorine groundwater with broadly distribution and vertically fluorine content changes observably. Hydrochemical types were complex under weakly alkaline environment. Most of the negative ion in phreatic water main was HCO - 3, but in confined water which was mainly SO 2- 4 and Cl-. Fluorion was controlled by the solubility product, which showed inverse ratio with calcium, and showed positive correlation with (K++Na+)/Ca2+ value. ©2010 IEEE. Source

Guo Q.,China University of Geosciences | Guo Q.,Water Resources University | Guo H.,China University of Geosciences | Guo H.,Water Resources University | And 3 more authors.
Journal of Hydrology

Little is known about hydrogeochemical contrasts between low and high As groundwaters and their connection to As mobilization in the Yinchuan Basin. Investigations were carried out to evaluate As distribution and geochemical processes for As mobilization in three regions, including piedmont proluvial fans (PA), dry farmland (DF) and paddy farmland (PF). Ninety-two groundwater samples, 4 surface water samples, and 66 sediments samples were collected and analyzed for chemical and isotopic components. Results show that low As groundwater is generally found in PA. However, high As concentrations (up to 105μgL-1) are mainly observed in groundwaters from DF and PF, which are associated with reducing conditions. High As groundwater is characterized by high concentrations of NH4 +, dissolved Mn, dissolved Fe and Fe(II), and low concentrations of NO3 - and SO4 2-. The intensive irrigation in PF recharges the aquifers by vertical infiltration of the diverted Yellow River water, and leads to the higher redox potentials and the lower dissolved As in comparison with those in DF. Environmental isotopes (δ18O and δD) show that evaporation due to the intensive irrigation plays a minor role in As enrichment. The positive correlation between As and dissolved Fe suggests that groundwater As would result from the reductive dissolution of Fe oxides. Besides, dissolved P may be involved in competing with As for binding sites on Fe oxide minerals. Sediment As ranges between 3.94 and 75.2mgkg-1. HCl-leached As accounts for 60% of total As in the sediments, while H3PO4-leached As accounts for 5%. Depth-matched samples show a good correlation between dissolved As and H3PO4-leached As in sediments. Arsenic distribution coefficient (Kd), calculated from H3PO4-leached As and dissolved As, ranges between 5.08 and 17.3cm3g-1, which generally depends on groundwater redox potentials. In reducing conditions, low values are found with As being preferentially partitioned into groundwater. © 2014 Elsevier B.V. Source

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