Holocene sedimentary of offshore and shallow sea and Xukou formation in Shandong are similiar in strata structures, vertical and transverse variation, sedimentary environment which formed in the same or similiar sedimentary environment and have similiar rock combination.

Also, it was in the pivotal period that Caledonina orogeny was transformed into Varis orogeny in late Devonian, Caledonian orogeny and its late stretch-rift event had been recorded in late Devonian deposition.