Early Continental Rift Basin Stratigraphy, Depositional Facies and Tectonics in Volcaniclastic System: Examples from the Miocene Successions Along the Japan Sea and in the East African Rift Valley (Kenya)

There are numerous stratigraphic studies regarding rift valley fill successions. The major understanding of the rift basins’ filling process was obtained from the Basin and Range regions and Rio Grande Rift, USA (for example, [1-4]); East African Rift Valley (for example, [5-7]); Suez Rift, Egypt (for example, [8-10]); Corinth Basin, Greece (for example, [11-13]) and so on. The initial stage of the rift basin evolution is characterized by the development of a series of small half-grabens. Basins become larger through the linkage of border faults of individual half-grabens [14]. Even after basin mergers, topographic lows of footwall among basins (accommodation zones before basin mergers) play an important role for sediment supply. The relay ramp developed between two normal faults dipping in the same direction (Figure 1), and its evolution, is crucial because it acts as the major entry point of the water and sediments to the basins [14-15]. The manner of sediment entry to the basins and the subsidence pattern strongly affect the architecture of basin-fills (for example, [16-17]), resulting in the formation of different systems tracts in different places within a basin at a given time [18]. In case of continental rift basins with lakes, the strata formation is much more complicated than in marine basins (for example [19-20]). The differences in sedimentation process between lake and marine basins are summarized in [21], suggesting that the terrestrial basin fills are not miniature marine basins because there were different amplitude base-level variations, linkage of climate