Detection of vertical movement of fluids behind the casing of groundwater observation wells

摘要

Focus of this work is the detection of vertical movements behind the casing of groundwater observation wells within the seal. A new multi-methodical and azimuthal logging tool, named Azimuthal-Annulus-Convection-Identification (AACI)-Log has been developed and tested. The measurement concept of this probe is based on the combination of three azimuthal measuring logs - contact temperature on the inside of the casing wall, backscattered gamma-rays (gamma-gamma density), and natural radioactivity (gamma ray). Consequently, a direction-oriented image of the annular space can be derived. Not only the reason (void, potential channel) but also the resulting effect (vertical movement of fluids) can be detected with the Azimuthal-Annulus-Convection (AACI) - Log at the same time.