According to many micropaleontologists, worldwide correlation of Tertiary successions in tropical and subtropical areas can be based on planktonic foraminiferal zones (chronozones). The taxonomic assemblages of such zones correspond to evolution stages of foraminifers. Current studies show that many of these zones can be traced in Japan and, to a certain extent, in Sakhalin, Kamchatka, and North America. For the first time, the stratigraphic scales of the north Pacific area can be tied rather confidently to the general world scale. Studies of nannoplankton, mammals (hipparions and Desmostyliidae in particular), isotopic age dating, paleomagnetism, and paleoclimatology have helped make worldwide correlations more reliable. Unfortunately, the planktonic fauna is very sparse in the Tertiary rocks of the northern Pacific region. Therefore, the establishment of regional scales must be based mainly on benthonic faunas. A change of systematic composition of some mollusk genera (Yoldia, Arcidae, Pectenidae, Turritellidae, and Acila) and the general number of species and newly appearing species in certain periods of their development are reflections of their evolution stages. These stages may be used to subdivide the sections into several zones and to correlate them. To distinguish such zones independently of the facies composition of the rocks, and to correlate them with the planktonic zones are the bases for applying the international scale in the boreal Pacific area. Seven such zones have been proposed for the Neogene of the USSR based on Yoldia and other groups; many of the zones have analogues in adjacent areas. Establishment of faunal succession relative to evolution is of great importance because the composition of each faunal complex in any particular section depends on stratigraphic facies; underestimating this circumstance in the past resulted in significant stratigraphic mistakes. To make the provincial schemes more exact, one naturally may use data on other faunal groups, floral successions, paleoclimatology, etc. The establishment of evolutionary stages of ancient basins, the changes of fauna and lithology dependent on these stages, and the study of faunal assemblages of unlike and similar facies of contemporaneous and successive levels are of great importance to work out regional stratigraphic scales. Distinguishing local subdivisions (suites, members, layers) that are related to facies peculiarities of the sequences, should be based on this framework of zones that was established according to evolution stages of faunas. Paleoecologic and paleogeographic methods also play a leading role in these studies. End_of_Article - Last_Page 2482------------