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Chapter ElO Preliminary results and potential for integrated stratigraphy of the volcano-sedimentary sequence in the boso peninsula, central Japan

1995; Elsevier BV; Linguagem: Inglês

10.1016/s0920-5446(06)80042-7

2352-2852

Masaki Takahashi, Masayuki Oda, Etsuo Uchida,

Paleontology and Stratigraphy of Fossils

This chapter discusses the preliminary results and potential for integrated stratigraphy of the volcano-sedimentary sequence in the Boso peninsula, Central Japan. The thick sequence of fossiliferous Neogene and Pleistocene marine sediments in the Boso Peninsula of Central Japan is one of the most promising sites in Japan for studies of Neogene geology and micropalaeontology. This sequence contains only one stratigraphic break (the Kurotaki Unconformity) and may provide a continuous stratigraphic record of the Miocene. Despite the abundance of volcanic intercalations, only some of the key tuffs are expected to be suitable for conventional K/Ar dating. In fact, about half of the volcaniclastic layers contained in this sedimentary sequence are basaltic scotia tuff, which is not suitable for dating. Although, half of the volcaniclastic layers are felsic tufts, biotite and/or hornblende, crystals suitable for radioisotopic dating are very rare. The correlation between siliceous and calcareous microfossils bioevents is one of the most important targets for the definition of a robust biostratigraphic model in the mid-latitudinal areas of the Northwest Pacific region.