RESERVOIR COMPARTMENTALIZATION ASSESSED WITH FLUID COMPOSITIONAL DATA

Fluid composition is a valuable addition to the battery of ''static'' data available during reservoir appraisal that can be used to predict the dynamic behavior of the reservoir later in field life. This is bec ause fluid data are not truly static; natural fluid mixing is a dynami c process that occurs over a long (geologic) time scale. Oil compositi onal differences, especially those that parallel changes in density, s hould be mixed rapidly by convection; their preservation indicates bar riers to fluid flow. Water variations, now measurable on conventional core samples by use of residual salt analysis (RSA), help identify bar riers to vertical fluid flow in oil and water legs.