Localization and characterization of the Zhangdian-Renhe fault zone in Zibo city, Shandong province, China, using electrical resistivity tomography (ERT)

A 2D ERT survey is performed along 10 cross-sections intersecting with the trace of Zhangdian-Renhe fault zone, a Quaternary active normal fault zone going from south to north across Zibo city, Shandong province, China. During the survey, the Wenner-α array with the strongest anti-electrical disturbance ability is adopted, and some ways to improve signal-to-noise ratio (SNR) of apparent resistivity data are performed. The reconstructed resistivity tomograms illustrate that Zhangdian-Renhe fault zone in Zibo city consists of 4 NW-striking normal faults which are the west branch (F1), the secondary fault of west branch (F1-1), the secondary fault of east branch (F2-1) and the east branch (F2). Fault F1 has NE apparent dip direction and 67° -75° apparent dip angle, and fault F2 SW and 60° -63°. The two faults are the main faults of Zhangdian-Renhe fault zone and form a graben. Subsequent geologic drilling records prove our inference. Our results present an important basis for the definition of seismic fortification level and new city planning in Zibo city.