Changes

==Example==

==Example==

[[file:evaluating-top-and-fault-seal_fig10-34.png|thumb|{{figure number|1}}Pressure depletion curves for two wells separated by an initially cross-sealing fault.]]

[[file:evaluating-top-and-fault-seal_fig10-34.png|300px|thumb|{{figure number|1}}Pressure depletion curves for two wells separated by an initially cross-sealing fault.]]

[[:file:evaluating-top-and-fault-seal_fig10-34.png|Figure 1]] shows the pressure depletion curves for two wells separated by an initially cross-sealing fault. The pressure depletion curve for well A is shown in light gray (top); that for well B, in black (bottom). The buoyant pressure at the crest of the oil column against the fault seal in well A remains constant as the pressure in well B decreases. The pressure differential (AP) increases until the displacement pressure of the fault zone is exceeded and the fault begins to cross-leak. A fault in the Beryl field has broken down during production.<ref name=ch10r10 /> A fault in the Akaso field, Nigeria, may have undergone this type of breakdown with a differential pressure of [[pressure::4137 kPa]] (600 psi).<ref name=ch10r40>Jev, B., I., Kaars-Sijpesteign, C., H., Peters, M., P., A., M., Watts, N., W., Wilkie, J., T., 1993, [http://archives.datapages.com/data/bulletns/1992-93/data/pg/0077/0008/1350/1389.htm Akaso field, Nigeria: use of integrated 3-D seismic, fault-slicing, clay smearing and RFT pressure data on fault trapping and dynamic leakage]: AAPG Bulletin, vol. 77, no. 8, p. 1389–1404.</ref>

[[:file:evaluating-top-and-fault-seal_fig10-34.png|Figure 1]] shows the pressure depletion curves for two wells separated by an initially cross-sealing fault. The pressure depletion curve for well A is shown in light gray (top); that for well B, in black (bottom). The buoyant pressure at the crest of the oil column against the fault seal in well A remains constant as the pressure in well B decreases. The pressure differential (AP) increases until the displacement pressure of the fault zone is exceeded and the fault begins to cross-leak. A fault in the Beryl field has broken down during production.<ref name=ch10r10 /> A fault in the Akaso field, Nigeria, may have undergone this type of breakdown with a differential pressure of [[pressure::4137 kPa]] (600 psi).<ref name=ch10r40>Jev, B., I., Kaars-Sijpesteign, C., H., Peters, M., P., A., M., Watts, N., W., Wilkie, J., T., 1993, [http://archives.datapages.com/data/bulletns/1992-93/data/pg/0077/0008/1350/1389.htm Akaso field, Nigeria: use of integrated 3-D seismic, fault-slicing, clay smearing and RFT pressure data on fault trapping and dynamic leakage]: AAPG Bulletin, vol. 77, no. 8, p. 1389–1404.</ref>