METHODS FOR EVALUATING INFLOW AND OUTFLOW IN A SUBTERRAEAN WELLBORE

摘要

A method for evaluating inflow or outflow in a subterranean wellbore includes acquiring first and second axially spaced pressure measurements in the wellbore. The pressure measurements may then be processed to obtain an interval density of drilling fluid between the measurement locations. A tool string including a large number of axially spaced pressure sensors (e.g., four or more or even six or more) electronically coupled with a surface processor via wired drill pipe may be used to obtain a plurality of interval densities corresponding to various wellbore intervals. The interval density may be measured during static conditions or while drilling and may be further processed to compute a density of an inflow constituent in the annulus. Changes in the computed interval density with time may be used as an indicator of either an inflow event or an outflow event.

主权项

1. A method for identifying an inflow event in a subterranean wellbore, the method comprising:
(a) processing a plurality of axially spaced annular pressure measurements to compute a plurality of annular interval densities; (b) monitoring the computed annular interval densities with time; and (c) evaluating a decrease in at least one of the annular interval densities or an increase in a differential flow rate as an indicator of an inflow event.