ÇAĞRILI KONUŞMALAR / KEYNOTES Invited Speeches ... - TPJD

Investigation of Different Deconvolution Methods for Pressure Transient Test
Analysis
Mehmet Ali Torçuk, Mustafa Onur
İstanbul Technical Uniıversity, Faculty of Mines, Department of Petroleum and Natural Gas
Engineering, İstanbul
Pressure-rate (p-r) deconvolution can reconstruct the constant rate pressure response from
the varying flow rate and pressure response for a well. Thus, more and longer time features
of a reservoir can be identified from the constant-rate pressure and pressure derivative signals
constructed by p-r deconvolution and compared with those signals constructed from the
conventional analysis methods. Because of these advantages of deconvolution, a variety of
deconvolution algorithms have been presented in the literature for last 50 years. Deconvolution
is an inverse problem and so small errors (or noise) in measured pressure and rate data can
produce large disturbances or oscillations in the solution of deconvolution. Hence, most of
the algorithms have aimed at removing the effects of noise on deconvolution. In this study, a
detailed investigation of the use of Coats et al.’s pressure-rate deconvolution algorithm which is
one of the oldest algorithms in this area and uses a constrained linear programming approach
to obtain the solution of deconvolution is presented. Using this algorithm, the vulnerability of
the Coats et al. algorithm to noise in pressure and rate data has been investigated in detail. We
also compare this “Linear Optimization” algorithm with the “Non-Linear Regression Analysis”
method which is a more recent deconvolution algorithm and has been proved to be a useful tool
for deconvolution for pressure transient test analysis.
Keywords: Deconvolution, Pressure Transient Test, Linear Optimization, Non-Linear Regression
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