Wellsite Handling of Poorly Consolidated Core, Inglewood Field, Los Angeles Basin

J. Gidman, A. E. Worthington, G. H. Newman

Cores of poorly consolidated lithologies are typically frozen to facilitate handling. However, growth of ice crystals can destroy the original fabric and result in erroneous measurements of petrophysical properties.

Poorly consolidated sandstone and mudstones from the Inglewood field were cored using plastic inner core barrel liners. Filled core barrels were lowered onto the catwalk by pullies. The entire plastic liner was pulled out onto a catwalk extension and was wiped and labeled. The core was cut into 3-ft segments using a pipe cutter for the liner and a deep-throat saw for the rock. Closely spaced special clamps were fastened around the liner to prevent distortion of the core during cutting.

The segments were placed on a slightly inclined surface with care to ensure that the core was not rotated. Rubber end caps with a 1-in. rectangular hole were taped to the bottom ends of the 3-ft segments, and plastic liner extensions were taped to the tops. Isocyanate polyol resin was poured in through the hole in the end caps. When this had hardened (5 min) the core segments were tipped to near vertical and resin was poured in to fill the annular space between the rock and the plastic liner.

The core was chilled to 32°F for transportation. The segments were slabbed along their length, and the resultant slab needed little further curing. Bed contacts are beautifully preserved and the resin has held the core without disturbance.

AAPG Search and Discovery Article #91038©1987 AAPG Annual Convention, Los Angeles, California, June 7-10, 1987.