常州市地面沉降以及用水化学标志研究的探讨

常州市过量开采第Ⅱ承压含水层的水使水位大幅度下降,造成含水砂层压密和粘性土层固结而导致地面沉降。试验资料表明该区粘性土层的压缩性较低,它们的压密主要是由主固结阶段完成的。视压榨液,浸提液成分和含水层多年水质的变化,以及抽水时水质与氚量资料说明粘性土层释水在造成本区地面沉降中起着相当重要的作用。这种条件下,用对含水层水化学成分的检测来监视地面沉降的发生、发展是一个经济可靠的方法。

ON THE LAND SUBSIDENCE IN CHANGZHOU CITY AND ITS RESEARCH ON THE BASIS OF HYDROCHEMICAL INFORMATION

The aquifer II is the dominat exploited one in Changzhou city. Excessive extracting water from this aquifer has made a greet drop in water level, resulting in compaction of sandy aquifer and consolidation of clayey aquitard, which in turn lead to land subsidence. The experiment data show that the compressibilty of the clayey strata in the research area is low and their comsolidation was completed mainly in the primary consolidation stage. The hydrochemical data of porous water samples released from clayey soils under pressure ( 30 atm. ) , soluble salts in clayey soil and the change of the composition in water of the aquifer in different time of a long period show that the water releasing from the clayey aquitards has played an important role in the land subsidence of this area. Therefore, hydrochemical analysis method shculd be considered one of the economical and reliable approach to monitor the behavior and magnitude of land subsidence.