Page 254 - Well Logging and Formation Evaluation

244 Well Logging and Formation Evaluation

Fitting a straight line through the points corresponding to transient
behaviour yields the model line, given by:

-
T T])
P w = 22 3 0.* (ln ( [ 24 + )
Hence the initial reservoir pressure is expected to be 226bar.
Using Equation 11.30, the product k*h can be estimated:

L 1 can be taken as 0, with P 1 = 226bar
L 2 can be taken at 1, with P 2 = 223bar

Hence:

m
* *(
*
kh = (12 * ) Q* *( L - L ) [2 p P - P )]
2
2
1
1
2
*
= (1 * ) 2 200 (24 *60 60 ) * . * *10 -3 * - ) [2 * .14 * -3 *10 5 ]
( 1
1
3
1
= . 3 686 *10 -13 m 2
Hence k = 36.86mD.
CHAPTER 12: HOMING-IN TECHNIQUES
Exercise 12.1: Worked Field Example of Magnetostatic Homing In

Start by entering the survey data from both wells in a spreadsheet. For
the survey well, derive columns for the x, y and z components of r, the
vector along the direction of the well bore. Convert these to unit vector
components by dividing by r.
Now derive the x, y and z components of unit vectors in the HS and
HSR directions using equations 12.10 and 12.11.
Derive the x, y and z components of the Earth’s field using equations
12.7–12.9. Convert these to the highside reference system using equations
12.12–12.14.
Convert the raw tool readings to B hs , B hsr , and B ax . Note that since the
tool face orientation is along the highside direction (there is no A y com-
ponent), B x = B hs , B y = B hsr and B z = B ax .
Derive F xy , F ax , F tot , HS dir and AX dir . You should end up with the fol-
lowing components: