Data from different sources now available indicate that the "Fenhe-weihe graben" is actually composed of three separate enechelon arranged grabens, converging toward SW.The threee grabens had developed from the longitudinal tensiule faults on the crest of three antclines since Eocene and Pliocene times respectively, which are members of the eastern frontal arc of the Qilianshan-Lüliangshan-Helansh epsilon structural system.The distribution of earthquakes, occurrences of present-day surface cracks, geothermal anomalies, ground water resources as well as some endemic deseases are found all closely related to the three grabens and the associated horsts.