Fluid Penetration and Formation Temperature Estimation by Inversion of Borehole Measurements

1990 ◽  
pp. 347-377
Author(s):  
S. Cao ◽  
I. Lerche ◽  
C. Hermanrud
Keyword(s):  
Formation Temperature ◽  
Temperature Estimation ◽  
Fluid Penetration

A Method for Formation Temperature Estimation Using Wireline Formation Tester Measurements

2005 ◽  
Author(s):  
Alexander F. Zazovsky ◽  
Sammy S. Haddad ◽  
Vladimir V. Tertychnyi
Keyword(s):  
Formation Temperature ◽  
Temperature Estimation

Estimation of formation temperature from bottom‐hole temperature measurements: COST ♯1 well, Norton Sound, Alaska

Geophysics ◽  
1988 ◽  
Vol 53 (12) ◽  
pp. 1619-1621 ◽  
Author(s):  
S. Cao ◽  
C. Hermanrud ◽  
I. Lerche
Keyword(s):  
Thermal Conductivity ◽  
Numerical Method ◽  
Time Scale ◽  
Efficiency Factor ◽  
Diffusion Time ◽  
Formation Temperature ◽  
Temperature Estimation ◽  
Bottom Hole ◽  
Free Parameters ◽  
Borehole Temperature

We recently developed a numerical method, the Formation Temperature Estimation (FTE) model, to determine formation temperatures by inversion of borehole temperature (BHT) measurements (Cao et al., 1988a). For more than two BHT measurements, the FTE model can estimate (1) true formation temperature [Formula: see text], (2) mud temperature [Formula: see text] at the time the mud circulation stops, (3) thermal invasion distance R into the formation before the formation is at the true formation temperature, (4) formation thermal conductivity K perpendicular to the borehole, and (5) efficiency factor F for mud heating in the borehole after mud circulation has stopped. The method optimizes three free parameters: τ (diffusion time‐scale), ε (scaling parameter related to the thermal invasion distance R), and [Formula: see text] (normalized efficiency factor for mud heating.

Formation temperature estimation by inversion of borehole measurements, Part II: Effects of fluid penetration on bottom‐hole temperature recovery

Geophysics ◽  
1988 ◽  
Vol 53 (10) ◽  
pp. 1347-1354 ◽  
Author(s):  
Song Cao ◽  
Ian Lerche ◽  
Christian Hermanrud
Keyword(s):  
Inverse Method ◽  
Synthetic Data ◽  
Thermal Recovery ◽  
Temperature Estimation ◽  
The North ◽  
Bottom Hole ◽  
The North Sea ◽  
Borehole Temperature ◽  
Fluid Penetration ◽  
Cooper Basin

Using nonlinear inverse techniques, we show that the change in borehole temperature with time, after mud circulation has stopped, can be used to provide very precise estimates of true formation temperatures and of mud temperature at the time circulation stopped. In addition, ruggedly stable estimates can also be made of the thermal invasion distance, the formation thermal conductivity, and the efficiency of heating the mud by the thermal recovery wave. It is well known that convective heat flow into (or out of) the formation influences the thermal recovery. We show that the flow rate at the borehole can also be obtained approximately from the borehole temperature measurements using the inverse method. Fidelity and reproducibility of the inverse procedure arc examined using synthetic data. Applications to field data from three wells in the Cooper basin of Australia and four wells in the North Sea confirm the accuracy of the method in satisfying the observed data, in determining true formation temperatures, and in assessing the magnitude of fluid penetration into the formation.

Sign in / Sign up

Export Citation Format

Share Document