圆明园遗址公园水文地质条件分析

通过遥感解译、水文地质调查、钻孔和抽水试验,结合区域水文、气象和地质等资料,对圆明园的水文地质条件有了初步认识:圆明园处在清河古河道范围内,浅层地下水可分为潜水和第一层承压水,含水层岩性以砂类为主,与湖水有直接联系的潜水含水层的渗透系数大于20md;20世纪50～60年代,圆明园所在区域地下水位较高,地下水补给湖水;近年来,受降水减少和地下水开采等因素影响,地下水位下降较大,湖水位高于潜水位,自然条件下湖水补给地下水。

An analysis of hydrogeologic conditions near the Yuanmingyuan Ruins Park

On the basis of decoding RS data, hydrogeological investigations, pumping tests in the east part of the Yuanmingyuan Ruins Park, and in combination of analyzing the regional hydrological data, climate and geology, this paper presents the preliminary results of the hydrogeological conditions of the Yuanmingyuan Ruins Park. The results indicate that, firstly, the Yuanmingyuan Ruins Park is located in the scope of an old river course of the Qinghe River and the shallow groundwater within the park can be divided into two types: phreatic groundwater and artesian groundwater with the lithology of the two aquifers belonging dominantly to the type of sandy soil, and the hydraulic conductivity of the phreatic aquifer exceeds 20 m/d . Secondly, till 1960's the regional groundwater table was in a higher status and the surface water was recharged by the groundwater. Since then, the regional groundwater table declined gradually as a result of being affected by several factors of climate change, groundwater exploitation, etc. Thus a situation that the surface water discharges to the groundwater has been caused in the area and the groundwater table will fall quickly if no surface water exists in the park.