| Popis: |
Summary A holistic formation evaluation approach to characterizing the naturally open fractures zones explained the basement negative temperature anomaly occurrence. For this purpose, using measurements of high resolution dual slim imager, acoustic cross-dipole, density, photoelectric factor, spectral gamma ray and temperature, few formation evaluation techniques were applied, such as structural facies identification, fracture aperture calculation, sonic anisotropy, brittleness index magnitude and polarity, Stoneley fracture identification, which, coupled with mudlogging data offered a conprehensive understanding of the naturally occurring fractured zones over the thermal conductivity anomaly. The presence of fractured facies identified on borehole images, decrease of density values, the occurrence of sonic anisotropy, changes in the brittleness index polarity, increase of the fracture density, increase of the fracture aperture and the presence of Stoneley reflection chevrons were used as arguments of water influx through conjugated open natural fracture system which generated the negative thermal anomaly. |
