Primary Study On The Palaeogeographic Framework Of Ludong Region In The Palaeozoic Period

In this article, based on research results about the strata and welwitschiopsida of Eastern Shandong area, and in combination with the analysis on the sedimentary and tectonic paleogeographic of Western Shandong area, we point out that there was no uplifted area existing in Eastern Shandong area in the Palaeozoic Period. The area was a tectonic unit independent of the North China during Cambrian to early Late Carboniferous. Controlled mainly by Sulu ocean basin, the region was composed of a set of marine and paralic deposits, but part of the strata of Upper Jurassic-Middle Devonian might not exist. During late Late Carboniferous to Permian, resulting from collision and convergence between Eastern and western Shandong area, continental sedimentary formation was formed. Since Triassic, Eastern Shandong area had brought about the end of sedimentation, with strong uplifting, erosion and absence of Palaeozoic formation, which didn't have deposits until Cretaceous.