Gabbroic peaks in the Abukuma Mountains
Northward view from the top of the Mt. Kuroishi (865 m). The front mountain is the Mt. Katasone (719 m), right hinder peak is Mt. Utsushigatake (994 m), and left side mountain behind the Mt. Katasone is the Mt. Hayama (897 m). The upper parts of those mountains consist of gabbroic rocks. When the boundary between the gabbroic masses and surrounding wall rocks is located on the level of 700 to 600 m high, the granodiorite around the gabbroic mass contains much amount of metamorphic sedimentary rocks, and in the case that the contact is lower than 500 m high, the dioritic hybrid rocks develop around the gabbroic masses. These facts indicate that the gabbroic masses are the roof pendant hanging down from sedimentary wall rocks over the Abukuma granitic rocks.
(Kazuya Kubo)
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