STUDY OF MODEL OF SLUG TESTS PERFORMED IN WELLS WHEN WELLS SCREENED ACROSS WATER TABLE

For the slug tests performed in wells screened across the water table in phreatic aquifer,the water injects into the wells through the upper and lower parts of the water table. By calculating the amount of the water flowed away from the lower part of the water table using the technique of tracer test with the concentration of solute,a new model of slug test in phreatic aquifer is built up;and the analytical solution of the new model is given. It’s different from the traditional ways to solve this problem,which usually do it by changing some coefficients to correct the radius of the wells. To demonstrate the correctness of this theory,a series of slug tests are conducfed in a fully penetrating well in the Jiangxiong Reservoir in Tibet. And then the hydraulic conductivity of the formation is calculated using the method. By comparing the result of this value to the calculating results of Bouwer-Rice slug,the results show that the proposed model can truly reflect the permeability characteristics of the formation. By analyzing the standard recovery curve of the slug test,it shows that curve can truly reflect the permeability characteristics of the aquifer when the curve decreases in a slower rate.