黄河三角洲地下水动态变化及其与地面沉降的关系

为了分析黄河三角洲地下水动态及其与地面沉降的关系, 利用多年地下水和地面沉降监测数据, 发现黄河三角洲广饶县和东营区的地下水动态变化剧烈且地面沉降严重, 含水层多处于超采状态, 浅、深层地下水降落漏斗先后出现.深层地下水降落漏斗中心水位下降速度达2~3m/a.近年来, 东营和广饶地面沉降漏斗中心沉降量和速率分别为155.1mm、28.2mm/a和356.0mm、64.7mm/a.借助GIS技术及数理统计法, 发现深层地下水降落漏斗与沉降漏斗空间耦合良好, 深层地下水位与地面高程呈线性正相关, 相关系数为0.92, 深层地下水过度开采已成为影响沉降的最根本因素.井灌区第三粘性压缩层成为地面沉降主要贡献层, 且深层地下水降落漏斗中心的地下水位已低于第三承压含水层临界水位, 沉降趋于严重. 

Groundwater Dynamic Evolutions and Relationsgip between Groundwater Level and Land Subsidence in tge Yellow River Delta

To analyze the groundwater dynamic and the relationship between groundwater level and land subsidence in the Yellow River Delta, drastic groundwater level depression and serious land subsidence have been researched by monitoring data of groundwater level and land subsidence for years. Persistent groundwater overexploitation has resulted in groundwater depression cones in both shallow and deep aquifers successively. The deep groundwater level decline rate of cone centers is 2 to 3m/a. In recent years, Dongying and Guangrao exhibit a typical subsidence area with cumulative settlement and subsidence rates of 155.1mm, 28.2mm/a and 356.0mm, 64.7mm/a, respectively. Using GIS and mathematical statistics, it is found that configuration of the subsidence cone is basically identical to the shape of the deep groundwater depression cone, and there exists a significant linear positive correlation between deep groundwater level and elevation in deep groundwater depression cone, with the correlation coefficient of 0.92. The deep groundwater overexploitation has been the most essential factor to land subsidence. The third compressed layer has become the main contribution layer of land subsidence in well-irrigated area. Because water level at centers of deep groundwater depression cone has fallen below critical water level of the third confined aquifer, land subsidence is becoming more and more serious.