Patent ID: 8701762
Filing Date: 2014-04-22
Classification: E21B

Abstract:
1. A method for determining a fluid influx profile and near-wellbore area parameters comprising: measuring a first bottomhole pressure in a wellbore, operating the wellbore at a constant production rate during a time sufficient to provide a minimum influence of a production time on a rate of a subsequent change of a temperature of the fluids flowing from production layers into a wellbore, changing the production rate, measuring a second bottomhole pressure after changing the production rate, measuring for each productive layer a fluid influx temperature as a function of time after changing the production rate, determining for each productive layer a derivative of the measured fluid influx temperature with respect to a logarithm of time, calculating relative production rates of the productive layers as where Y h t h t determining for each productive layer a fluid influx temperature change corresponding to the time at which the temperature derivative becomes constant, and calculating skin factors of the productive layers as θ=ln(r r r θ r c is a non-dimensional coefficient, ε P P ΔT