Japanese words equivalent to the terms Palaeogene and Neogene

Suzuki, Hisashi; Ishida, Shiro

doi:10.5575/geosoc.111.565

Cited by 1 publication

(2 citation statements)

References 6 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The Akita and Niigata basins (Figure 1) formed as parts of a large-scale failed rift (the Nihonkai Tobu rift system of Suzuki (1989) or the northern Honshu rift system of Sato et al (2004)) during the final stage of rifting in the Sea of Japan (Nakajima, 2013(Nakajima, , 2018. During the post-rift stages, these basins remained as N-Selongated troughs parallel to the Northeast Japan arc, and accommodated deposition of thick Neogene sediments (Iijima et al, 1988;Nakajima, 2013Nakajima, , 2018.…”

Section: Geologic Settingmentioning

confidence: 99%

See 1 more Smart Citation

U–Pb and fission‐track dating of Miocene hydrocarbon source rocks in the Akita Basin, Northeast Japan, and implications for the timing of paleoceanographic changes in the sea of Japan

Nakajima

Iwano

Danhara³

et al. 2023

Island Arc

View full text Add to dashboard Cite

Middle to Late Miocene organic‐rich siliceous mudstones (Onnagawa Formation) in the Akita Basin, Northeast Japan have been an important target for both paleoceanographic studies and hydrocarbon exploration in Japan. However, the reliable age of their formation has remained poorly constrained. Here, we report new zircon U–Pb and fission‐track ages of the Onnagawa Formation from a previously well‐studied outcrop route in the Yashima area, central Akita Basin. The thin tuff bed in the lower Onnagawa Formation was dated at around 11.6 Ma, whereas thin tuff beds in the upper Onnagawa Formation was dated at 10.4–9.6 Ma. The new age model constrains the base of the succession as older than 15.6–13.8 Ma and the top of the succession as 8.7–8.2 Ma. The results suggest that the lowest part of the succession was deposited before the Onnagawa Stage. The new age model indicates a rapid deposition in the lower Onnagawa Stage. The new age model also clarifies a temporary decrease in the sedimentation rate during 10.9–9.4 Ma, which coincided with a hiatus or slow deposition reported from other areas along the Sea of Japan coast. The new age model also revises the timing of paleoceanographic changes, of the best hydrocarbon source horizon, and of hydrothermal activity responsible for seafloor chemoautotrophic communities in the Akita Basin. This revised timing reveals that the onset of paleoceanographic changes from oxidizing to anoxic bottom environments favorable for hydrocarbon source rock formation was closely related to the tectonic uplift of the Northeast Japan Arc at ~12 Ma, whereas the timing of hydrothermal activity was related to the following extensional tectonics at ~9 Ma. The results of this study thus shed light on hitherto unclarified relationships between tectonics, volcanism, and paleoceanographic changes in the Sea of Japan.

show abstract

Section: Geologic Settingmentioning

confidence: 99%

“…For this reason, new, F I G U R E 1 Map showing the Miocene Akita and Niigata basins, and the location of the Yashima area. Blue hatched areas represent distribution of Neogene thick sedimentary basins after Suzuki (1989). Dashed rectangle shows the area of Figure 2.…”

Section: Introductionmentioning

confidence: 99%