Through analysis of distribution features of vertical displacement in different geological periods

the growing process of Changyuan fault has been inversed

which might be originated from two isolated fault segments.This study shows Changyuan fault has different growing characteristics in different geological periods.It consisted of the two individual normal faults in the Es

4

depositional stage

they were joined together and became one fault in the Es

3

depositional stage.However

each segment still had its own displacement features as independent normal fault

i.e.the largest vertical displacement to be in the central part of the fault segment

and became smaller and smaller to both ends.Both fault segments separately controlled the half-grabens

with displacement deficit on the joining site

where a transverse uplift was formed separating the half-graben.An integrated fault system had been successively formed in the Es

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to Dongying stage.The depo-center then began to migrate toward the central part of Changyuan fault

the transverse uplift began to subside

and an unified half-graben was then formed on the hanging wall of Changyuan fault.