System and method for determining pressure transition zones

摘要

A method and apparatus for estimating a pressure transition zone in a borehole is disclosed. A parameter indicative of formation fluid pressure at a plurality of borehole depths is measured. A global trend of the parameter is determined over a first depth interval and a local trend of the parameter is determined over a second depth interval. A relation is determined between the global trend and the local trend, and the pressure transition zone is determined from the determined relation between the determined global trend and the determined local trend.

主权项

1. A method of determining a pressure transition depth in a borehole, comprising:
obtaining measurements of a parameter indicative of formation fluid pressure at a plurality of borehole depths extending from a starting depth to a selected depth; determining a global trend line of the parameter using the obtained measurements over an entirety of a first depth interval extending from the starting depth to the selected depth; determining a local trend line of the parameter using the obtained measurements within a second depth interval that includes the selected depth and is a subset of the first interval; determining a deviation between the global trend line and the local trend line; and determining the pressure transition depth when the determined deviation between the global trend line and the local trend line meets a selected criterion.