A ground surface break may not be indicative of a fault. However, if the surface feature is supplemented with geophysical data, uncertainty can be reduced, as demonstrated here with three different electrical methods to verify the suspected Tachia-tung fault, near Tachia, Taiwan.
Ground penetration radar imaging reveals a prominent reflector which is offset vertically by about 2.6 m at depth about 2.3 m across the scarp. Schlumberger depth sounding exhibits a disrupted marker that links the loci of maximum apparent resistivity at greater depths.
Resistivity image profiling (RIP) surveys across the scarp yield either zones of low resistivity (two profiles) or disruption of high resistivity zones (one profile); those anomalies are suggestive of a low angle thrust fault.