Page 206 - Origin and Prediction of Abnormal Formation Pressures

SEISMIC METHODS OF PRESSURE PREDICTION 181

Pressure
(ppg) Fracture Pressure - Pore pressure
lEO 500
0.75
1000
1.5
2.25 1500

3
2000
3.75

4.5 2500
5.25
3000
6

3500

4000

4500
Fig. 7-4. The range of differential pressure (fracture pressure minus pore pressure) between 1 and 6 ppg.
(Modified after Lee et al., 1999.)

orma, oomoaot,on tren sands s a, s

-Unc~ i '
0
0
0
12
nesville salt

f'~ 16
Carbonate and salt tren~l:~~~k

20
Possible top Norphlet sand ~...~
I
24 I i ! I t I i
6 8 10 12 14 16 18 20
Interval velocity, 1000 ft/sec

Fig. 7-5. Intercept velocity analysis for a south Mississippi prospect demonstrating the impact of lithology
change on the velocity trend. (Modified after Reynolds, 1970.)