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Ground subsidence refers to natural factors or human factors appear under ground elevation reduce the phenomenon. Ground subsidence is a natural disaster, it's happening has some geological factors. However, with the economic and social development, increasing the scope of ground subsidence, sedimentation rate is growing. Overall, in the process of development of land subsidence, human factors relative to natural factors contribute to a more prominent role is greater. A large amount of groundwater exploitation in urban areas, land subsidence phenomenon is more pronounced. With the continuous economic and social development, Jining City, the demand for water is increasing, due to the long over-exploitation of deep groundwater, forming a regional deep groundwater depression cone and induced land subsidence, resulting in a reduced ability to urban flood control, fissure, crack houses, city pipeline rupture, ground deformation and other road hazards. Currently, Jining City, land subsidence has developed sustainable economic and social development to limit the environmental geological problems to be solved. In-depth study of Jining City, hydrogeological and engineering geological conditions established based on a quasi-three-dimensional groundwater flow - land subsidence coupled one-dimensional numerical model of groundwater flow model to analyze the sources and sinks, and use Processing Modflow and its subpackages Interbed storage Package coupled model was solved by repeated parameter adjustment and fitting, get a reasonable hydrogeological parameters, more accurately simulate the Jining area ground subsidence. Using ground subsidence prediction model of groundwater mining conditions were unchanged and groundwater exploitation has slowed in both cases in 2020 land subsidence trends. Prediction results showed that: ① In 2005 groundwater levels continued to 2020, forecast 2020 land subsidence situation: a sharp decline of deep groundwater funnel center, also increasing the amount of land subsidence, ground subsidence funnel 220mm centers decreased from 2005 to 480mm. ② full use of foreign sources in the South and other works under the conditions of exploitation of groundwater exploitation reduced 2005 level of 90% of the cases, changes in land subsidence prediction in 2020: deep groundwater level decline eased, ground subsidence funnel Center settlement of 220mm from 2005 down to 296mm. From the predicted results, for the special geological conditions of Jining City, with the decrease in exploitation, land subsidence of the grim situation greatly reduce sedimentation rate slowed, reducing the amount of the settlement, the water table is restored, possibly even a small amount of ground subsidence rebound phenomenon. Finally, from the optimization of groundwater extraction program to strengthen groundwater use and management perspective presented Jining ground subsidence control countermeasures for the realization of Jining City, the sustainable use of groundwater resources provide important basic information and scientific evidence.
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