Integrated interpretation of galvanic and induction measurements by inversion methods

摘要

Accurate estimation of residual and movable hydrocarbon requires precise estimation of the formation resistivities in the flushed and uncontaminated zones. The estimation of formation resistivities is commonly done by interpreting the data provided by galvanic (mainly laterolog) and induction devices. Different physical principles govern these devices. In galvanic tools, the voltages being measured are related to the surface charge densities at the interfaces between adjacent media of different resistivities, whereas in inductiontools, the voltage induced in a measuring coil results from the magnetic fields due to alternating currents flowing in the surrounding formation.