1. Determination of water-conducting coefficient(T) of water-bearing bedUnder the same condition, the thicker water-bearing bed and the coarsergrain are accompanied by higher apparent lateral resistance (Rt),representedby Rt = Q2·h2; moreover, the water-conducting coefficient(T) are also dependenton the thickness and structure of the water-bearing bed, as exprassed by T=K·h. It might therefore be seen that positive correlationship exists between Tand Rt, and that the water-conducting coefficients can be evaluated by drawingthe T-Rt correlation curve.Rt was determined by interpretation of field electrical sounding curves;Water-conducting coefficients of the aquifer were obtained on the basis of datafrom seven known withdrawal holes; Through a comparison between the calcu-lated T values and Rt values, the T-Rt correlation curves (being straight lineshere)of Q3 sand-pebble layer and Q2 argillaceous pebble layer have been estab-lished respectively. Calculation shows that T-Rt correlation coefficient of Q3 layer is y=0.964, suggesting the reliability of the correlation curve. On thebasis of T-Rt correlationship, a map of "distribution of water-conducting coeffi-cients" has been compiled, and some parameters have been figured out:permea-tion coefficient of Q3 layer is 80—120 m/day, Rt/T 2.13—2.66, K of Q2 layer40—50 m/day, and Rt/T 5—8.2. The evaluation of effective porosity(ψ)of water-bearing bedThe formula ρs=ψ-mS-nρw has been used for this purpose. In the field, elect-rical sounding technique was adopted to evaluate the resistivity(ρs)of water-be-aring beds in 11 known drill holes. The water samples collected in the field wereanalysed at laboratory. According to the diagram of relationship between strati-graphic water (ρw)and mineralization intensity (c) at 16℃,ρw value for eachdrill hole was determined; taking m=1.5,ψ value for each hole was evaluatedwith the above formula.values of Q3 layer range from 0.1796 to 0.3444,mostly 0.20—0.25, which are in agreement with the ψ value (0.25) obtained inlaboratory, and are also close to the empirical value(0. 23—0. 26) of gravity watersupply.
出版日期: 1987-04-24
引用本文:
张健, 吴占昌, 袁跃国. 电法测定水文地质参数的尝试[J]. 物探与化探, 1987, 11(2): 115-129.
Zhang Jian, Wu Zhanchang, Yuan Yueguo. AN ATTEMPT OF USING ELECTRIC METHOD TO DETERMINE HYDROGEOLOGICAL PARAMETERS. Geophysical and Geochemical Exploration, 1987, 11(2): 115-129.