Groundwater Quality And Land Subsidence Environment Influence Study Due To Exploitation In HangZhou

Groundwater is one kind of precious natural resources and also a fundamental element of environment. "Population, resource, environment" these three large problems the world in the nowadays confronting with, are all connected with ground water resources directly or indirectly. With the unceasingly increasing of population and the promptly developing of city, industry and agriculture, the amounts of groundwater that human being needing are rapidly increasing. But, because of exploitation groundwater of Quaternary loose sediment leads series of environment geology, especially the land-subsidence. Therefore, analysis on groundwater water system roundly and accurately, carrying out accurate groundwater quality and quantity, and forecasting possible land subsidence, are the premise and basis that we make use of ground water resources effectively. The quaternary-loose-pore aquifer in HangZhou plain is studied.The groundwater quality and quantity is appraised, and analyzing the problem of possible land subsidence. The main content of the article as follows:(1) On the basis of investigating Quaternary loose pore aquifer hydrogeololgy condition, geological environment problem owing to groundwater exploitation is dissertated in detail.(2) Under the premise of full understanding the history and current situation of aquifer water quality, use the random selecting factor of blurred synthesis deciding law to evaluate the water quality in HangZhou.(3) The object of the study is Quaternary pore aquifer of HangZhou plain .Aquifer can be divided into phreatic aquifer, weak permeable aquifer, the confined aquifer. On basis of carrying out system analysis to hydrogeololgy condition about this area, the concept model about studying area is built.(4) On the basis of establishing the concept model, the entire three dimensional finite difference unsteady flow mathematical model is built.By using observation borehole datum from January 1, 2004 to December 31, 2004, the hydro-geologic parameters are identified and calibrated.(5) Using the model which have been distinguished and verified to forecast the confined aquifer, when the water table control during the period of 15 m, 20m 25m, calculate the quantity of confined water is calculated. Under the three forecast schemes, the relevant land subsidence environment effect is analyzed.