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IUGG XXIV General Assembly July 2-13, 2007 Perugia, Italy
(S) - IASPEI - International Association of Seismology and Physics of the Earth's
Interior
JSS017 Poster presentation 2394
Estimation of formation temperature from measurements in near bottom
zone
Mrs. Anna Semenova
Technical Physics and Rock Physics Russian State Geological Prospecting University IASPEI
Yury Popov, Vyacheslav Pimenov
A. Semenova, Yu. Popov, V. Pimenov Russian State Geological Prospecting University, Moscow, Russia
Experimental data on bottom hole temperature (BHT) are important in geothermal research when it is
impossible to obtain undisturbed formation temperature distribution or when temperature logging could
not be performed. Sometimes BHT measured in several depth levels during drilling company are used to
give information on equilibrium temperature gradient for heat flow density estimations. It is important
(1) to know conditions of BHT measurements which can exclude significant discrepancy in experimental
temperature data and real formation temperature, and (2) to estimate possible systematic difference
between experimental data and undisturbed formation temperature to provide necessary corrections in
the experimental results. We calculated 2D temperature field for several typical wells and considered
dependence of well axis temperature on time in different distances from a bottom-hole (1-20 m).
Possible natural convection in the well was taken into account using different values of mud effective
thermal conductivity in the calculations. Calculation results show that the temperature measured in the
well axis near the bottom can differ significantly from undisturbed formation temperature (1-10 K
depending on a well depth within a range 500-5000 m) if optimal regime parameters for temperature
measurements are not used. Our calculations result in recommendations for the measurements of
bottom hole temperatures with optimal conditions providing accepted correspondence between the
measurement data and undisturbed formation temperature. Authors wish to acknowledge generous
support of Schlumberger Oilfield Services, an international company in oil and gas industry.
Keywords: bottom, hole, temperature