管外电阻率法在深水井成井工艺中的应用

Application of outside-tube resistivity method in deep well forming technology

在沿海及咸淡水分布区的水井成井工艺中,需要对下方的淡水层回填砾料。若按经验计算法计算出的投砾量进行投砾,实际回填高度与理论计算高度会有很大偏差,这种偏差往往造成井孔报废。依据管外电阻率法测量井壁空间投砾与没有投砾两种状态下产生的电性差异,可以准确确定投砾高度,从而提高成井的工艺水平和质量,避免下部的井水质量受到上部咸水的破坏。

In the well forming technologies in costal and saline-freshwater areas,the lower freshwater layer should be filled with gravel.If the filled gravel volume is calculated through empirical formulas,the practical filled thickness may differ from theoretically calculated value.The difference always causes the abandonment of the well.The measurement of electrical conductivity difference between gravel filled and unfilled spaces outside of the well tube by resistivity method can accurately determine the gravel filled thickness;it improves well forming technology and well forming quality and prevents the upper saline water from damaging the well water in lower part.