Page 55 - Reservoir Geomechanics
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39     Pore pressure at depth in sedimentary basins



                    a.
                                 Pressure history - Lapeyrouse field, Pelican sand
                       70

                       60             FAULT BLOCK III
                       50
                      Corrected BHP (MPa)  40  Hydrostatic Pore Pressure  BLOCK II
                                                FAULT
                               FAULT
                              BLOCK I
                       30
                       20

                       10
                          Average depth: 14,600 ft
                       0
                       01/01/60    01/01/70     01/01/80     01/01/90
                                           Date



                b.






















                               PELICAN SAND









                                                0                 2 miles
               Figure 2.10. The Pelican sand of the Lapeyrouse field in southern Louisiana is highly
               compartmentalized. Note that in the early 1980s, while fault blocks I and III are highly depleted,
               fault block II is still at initial reservoir pressure (modified from Chan and Zoback 2006). Hence, the
               fault separating wells E and F from B and C is a sealing fault, separating compartments at pressures
               which differ by ∼55 MPa whereas the fault between wells B and C is not a sealing fault.
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