Field Trip in the Northern Part of Komatsu City
Guide: Yasuhiro Tomii
(11th Oct., 2000)
This field trip was held in the working field of Yasuhiro Tomii. Continuous walking along a broad valley. Almost no outcrops in his field. They could be found occationally in the floors of smalll streams.
Climbing a narrow pocket where Japanese cedar trees are afforested. Almost no outcrops excepting several falling rocks of green-tuff gravels. A small outcrop consisiting of semi-consolidated sandstone and mudstone, named "Tenguyama Formation" was found on the ridge.
A typical outcrop of green-coloured tuff. A porphylitic dyke intruded in the the tuff in an outcrop (left). On the other hand, the green-tuff seems to be strongly brecciated in the other outcrop where a large fault might appear.
Tenguyama Formation at a ridge in his field. The formation is composed of the upper fine-grained sandstone and the lower medium-grained sandstone. A palaeosoil layer was intercalated between them. A chard material concentration zone underlies the palaeosoil layer.
The last outcrop in this trip. Fine-grained tuffs and medium-grained tuffs are thinly alternated. Deformed layers that seems to be a fluidized layer were observed.
