Publications

The PTA (pressure transient analysis) is sometimes affected by pressure noise, especially in case of DST in a high permeability gas reservoir. The pressure build up is so quick in a high perm reservoir, that the pressure becomes stable within a few psi range after a few hours. In this circumstance, any pressure noise with more than 0.1 psi magnitude affects the interpretation of the pressure data. The pressure noises come from tidal effect, operation noise, gauge drifting, tubing movement, and DST tool malfunction, etcetera.This paper will introduce actual gauge data from DSTs with some noise and show the current best interpretation of those data. Some of the DST strings were designed specially to prevent pressure noise due to tubing movement. Those are significant lessons learnt for future DST strings and operation designs.