Feasibility Study of Using Perforation Inflow Test Analysis to Estimate Reservoir Parameters

Conventional well tests cause production lost in their relatively long duration, especially in low permeability reservoirs, where receiving infinite acting response might require too much time. In this paper, after a brief review of a new well testing method called Perforation Inflow Test, a case study is presented to demonstrate both time saving and accuracy of one such test. An attempt is made to estimate key parameters of a deep, low permeability and over pressured gas reservoir through analyzing its pressure response, after perforating it in underbalanced conditions. Due to low permeability of the reservoir, late time pressure response was not received and the test was terminated in the transition from early time to late time. Hence, initial estimates of permeability, skin and pressure were not necessarily correct. To overcome this problem, pressure modeling was used to history match the modelgenerated pressure with the actual pressure. At the end, the results of a consequent conventional build up test are compared to the PITA results. As will be detailed in the paper, the results of build up test are in good agreement with the PITA results which nominates PITA as a precious method for obtaining key reservoir parameters, reducing both time and cost.

Feasibility Study of Using Perforation Inflow Test Analysis to Estimate Reservoir Parameters Keywords:

reservoir parameters , Perforation Inflow Test Analysis , PITA , well testing , permeability