Analysis of Well Tests in Afyon Ömer-Gecek Geothermal Field, Turkey

Abstract

In this work, analyses of pressure transient tests (such as multirate tests, conventional drawdown/buildup tests, and interference tests) conducted in the Afyon Ömer-Gecek geothermal field, Turkey, are presented. The pressure transient tests were conducted at six different wells. The pressure data were acquired by downhole quartz gauges, and thus, amenable to the applications of modern well-test analysis techniques such as derivative and deconvolution. Deconvolution analysis based on recently proposed robust algorithms was found useful to extract more information from the variable-rate well tests conducted in the field. In general, the pressure data analyzed indicate that the wells’ productivities are quite high, but influenced by non-Darcy flow effects and are producing in a complex fractured/faulted network system. The estimated values of permeability-thickness products (kh) from buildup and interference tests range from 40 to 1900 darcy-m, whereas porosity-compressibility-thickness products (cth) estimated from the interference tests range from 2.91x10-4 to 1.06x10-2 psi/m.