1964 Paper F

WELL-SITE RECORDING OF MOVABLE OIL PLOT

by M. L. Millican, L. L. Raymer, and R. P. Alger Schlumberger Well Surveying Corporation

ABSTRACT

The Movable Oil Plot field computer provides a continuous well-site interpretation log. Using data from Sonic, Laterolog, and Microlaterolog surveys, the computer produces a quick-look qualitative log of porosity, water saturation, residual oil, and movable oil.

Porosity is computed from sonic measurements of interval transit time. Estimates of the water-filled porosities of the flushed and undisturbed zones are provided, respectively, by computations using the Microlaterolog and Laterolog readings. Interpretation is accomplished through comparison of these computed porosities.

The continuous computation, immediately available at the time of logging the well, insures that all formations are examined; and the graphical presentation permits rapid evaluation of the results. The log analyst can instantly separate possibly productive horizons from those of no interest.

The technique, which is most effective in wells drilled with salt muds, has some limitations. The operation, advantages, and limitations of this technique are discussed and documented with field examples.