Page 105 - Petroleum Geology
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Fig. 4-5. Block diagram of petroleum in a fault trap.
Fig. 4-6. Block diagram of petroleum in a stratigraphic (mainly unconformity) trap.
As with anticlinal traps, fault traps may include single or multiple reser-
voirs, and the oil/water contacts of multiple reservoirs are usually at different
levels, but may be the same. Displacement of a fluid contact in the same re-
servoir (lithological) unit across a fault is taken as evidence of fault trapping;
and conversely, observation of different fluid contacts in the same litholog-
ical unit is regarded as evidence of an intervening sealing fault.
The accumulation of petroleum in stratigraphic traps (Fig. 4-6) exists es-
