Early - Middle Paleozoic geology of the Japan Sea Continent - Ocean Transition Zone (review). Pt 1
On the basis of extensive, to a large extent, the original material a correlation of the Lower - Middle Paleozoic local-rank stratigraphic divisions of various of the Japan Sea Continent - Ocean Transition Zone (OZ). The Russian Primorye, Northeast China, Korea, the Japan Sea Depression, Japan Islands - correlation is carried out for the first time. The need for this study is primarily due to the fact that the accumulated to date, numerous data on stratigraphy and lithology of the Lower and Middle Paleozoic regions of the Japan Sea zone (especially in Primorye), in fact, remain not linked. In addition, the stratified and non-stratified magmatic complexes of these ages, representing volcanic, subvolcanic, volcano-plutonic and plutonic generations are allocated. Thus, elements of the formational analysis, developed by N.S. Shatsky and N.P. Heraskov are used in the work. In the structures superimposed on Precambrian Massifs, considered sediments are usually well traced along the strike, while in Polycyclic Mobile Belts they lie down often in the form of olistoliths in Mesozoic mixtites or in large xenoliths in uneven-age granites, that creates considerable difficulties at their mapping and correlations. Submarine Ordovician, Silurian and Devonian sediments of JZ accumulated in similar paleogeographic conditions, practically in the same sediment basins, which incorporated to the Central-Asian Sea, the Sea of Okhotsk and the Australian Sea. Continental deposits of the investigated territory are presented by the Devonian strata, including the numerous vegetative remnants, widespread as well in the Central Kazakhstan, Western Siberia, Okhotsk Region and in Southern China. As a result of the display of intensive Mesozoic-Cenozoic tectonic genesis and tectonic opening of the margin Japan Sea, Lower and Middle Paleozoic sediments in JZ in many cases have been strongly dislocated and have well remained, basically, within residual Precambrian Massifs.