Maekura Lavas and Pyroclastics

[ Top ] [ Japanese ]

Maekura Lavas and Pyroclastics Shimazu et al., 1983

Type locality: Maekura, Tsunan city, Nakauonuma county, Niigata prefecture
Volcanic rocks
Pleistocene (3.22 Ma, K-Ar)

Lithofacies: Calc-alkaline
Lithofacies: Augite hypersthene andesite lava, Pyroclastic flow deposit, Volcanic mudflow deposit

Thickness: 200 m
Upper limit Unconformity (Takayamazawa-Onizawa Pyroclastic Flow Deposit, Uenohara Welded Tuff, Kusso Formation)
Lower limit: Unconformity (Uonuma Formation, Ketto Formation, Wayama Tuff Member)

Maekura Stage
[ Upper ]
~~~~~~~~~~~~~~
Maekura Lavas and Pyroclastics
~~~~~~~~~~~~~~
[ Lower ]

Torikabuto volcano
[ Upper ]
+__+__+__+__+_
Stage 3
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Stage 2
~~~~~~~~~~~~~~
Stage 1
~~~~~~~~~~~~~~
Maekura Stage
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[ Lower ]

------ Conformity, ~~~~~~ Unconformity, ~~~--- Local unconformity, '''/,, Interfingered, :::::: Fault, /--/-- Thrust, +__+__ Ground surface, ?--?-- Unknown

Distribution: Maekura, Tsunan city, Nakauonuma county, Niigata pref.; Nakatsu river - Takayama creek, Sakae city, Shimominochi county, Nagano pref.

Igarashi et al. (2007) Jour. Geol. Soc. Japan, vol.113, no.11, pp.565-584 DOI
Shimazu and Tateishi (1993) Geology of the Naebasan District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 90p. (in Japanese with English abstract 5p.)