ABSTRACT
The mathematical model of the Two Logs Method (TLM) is based on the assumption that in deep wells the effective temperature of drilling mud at a given depth can be assumed to be constant during the drilling process (Kutasov 1968; Kritikos and Kutasov 1988; Kutasov 1999). As was shown earlier (Kutasov 1999) for moderate and large values of the dimensionless circulation time (tD > 5) the temperature distribution function TcD (rD, tD) in the vicinity of the well can be described by a simple formula
t rr r R r rr
χ= = =
1 ,
2.184, 5 10 , in o D
R D t
D t
= + = ≤ <
where rin is the radius of thermal infl uence , tc is the drilling fl uid circulation time (at a given depth), rw is the well radius, rD is the dimensionless radial distance and γ is the thermal diffusivity of formation. Thus the dimensionless temperature in the wellbore and in formation at the end of mud circulation (at a given depth) can be expressed as:
1 , 0 1 ln
( , ) 1 , 1 .
