R.A. Lambert, P.S. D‘Onfro, 1983. "Thrust Fault, North Africa", Seismic Expression of Structural Styles: A Picture and Work Atlas. Volume 1–The Layered Earth, Volume 2–Tectonics Of Extensional Provinces, & Volume 3–Tectonics Of Compressional Provinces, A. W. Bally
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Figure 1 is a marked time section from North Africa. Faults left of center are interpreted to be thrust faults and were encountered in a nearby well. The most striking feature on this seismic section is the velocity pull-up underneath the hanging wall. The pull-up is caused by thrusting of a sliver of high-velocity material over lower-velocity material, as shown in Figure 2, a velocity-depth model of the time section. Again, depth and velocity data were obtained from the nearby well and projected into the seismic section.
The fault at the left end of Figure 1 has some characteristics of so-called "listric normal faults" observed in thrust belts. It overlies a thrust fault ramp, dips in the same direction as the thrust, and curves slightly, becoming less steep with depth. In Figure 2, the normal fault is interpreted to cut the thrust faults. Another plausible interpretation is that the fault soles out into the thrust plane. Unfortunately, data quality is not good enough below 2 secs to determine which interpretation is correct.