The Toyora Group is thick, and divided into the
Higashinagano,
Nishinakayama,
Utano, and
Ohchi Formations in ascending order. The group rests
unconformably on the tilted
Paleozoic Renge Metamorphic Rocks and
Toyohigashi Group, formations assigned to the
Akiyoshi Belt. The Toyora Group is separated by a
parallel or locally
angular unconformity with the
Latest Jurassic to
Early Cretaceous Toyonishi Group. The Toyora Group sediments are composed mainly of
black mudstone, sandy
mudstone,
sandstone,
conglomerate that deposited in a
shallow marine embayment. The mudstone and very fine-grained sandstone beds are often bioturbated by an
ichnogenus Phycosiphon. == See also ==