Patent ID: 7937999

Claim:
A method of estimating an actual temperature of a selected region of an earth formation penetrated by a borehole, comprising: using a sensor to make a measurement relating to a property of interest of the selected region of the earth formation; using a sensor to measure a temperature of a mud in the borehole over time proximate the selected region; estimating a virgin formation temperature of the selected region; estimating a thermal conductivity of the earth formation; estimating a heat capacity of the earth formation; and using a processor to: estimate a time difference (“elapsed time”) between a time the borehole is drilled proximate the selected region and a time at which the measurement relating to the property of interest of the selected region is made, and estimate the actual temperature of the selected region at the elapsed time using the estimated elapsed time, temperature of the mud measured over time, virgin formation temperature, thermal conductivity of the earth formation, and heat capacity of the earth formation.