Geology Reference
In-Depth Information
Fig. 7.2.
Normal faults on a vertical profile from a time-migrated 3-D seismic reflection volume.
V.E. about 1 : 1. The profile is from the Gilbertown graben system, southern Alabama (modified from
Groshong et al. 2003a).
a
Uninterpreted.
A:
fault trace between arrows;
B:
reflectors hang over fault
trace;
C:
disturbed zone along fault trace.
b
Interpreted. The faults indicated with
heavier lines
have
been identified in nearby wells.
Numbers
next to the faults are heave (regular type) and throw (bold).
Throws are determined from the heaves using Throw = Heave times tan (fault dip). Only the most
obvious faults are interpreted below the top of the Eutaw
trace (Fig. 7.2a, location B), obscuring the exact location of the fault and its separation. At
location B (Fig. 7.2a) the overhang makes the fault look like it is reverse, although it is
actually a normal fault (c.f., Fig. 7.2b). Local disruption of reflectors or lack of reflectors
in the fault zone may also make the location uncertain (C, Fig. 7.2a). The termination of
