Chemical analysis of dolerites and a gabbro at the Daigo district in Ibaraki Prefecture, central Japan.

Abstract

Rock samples from dolerite and gabbro dykes intruding into cherts and sandstones of the Jurassic Ashio Terrane in the Daigo district, northwestern Ibaraki Prefecture were collected. Petrography of three dolerite and one gabbro samples were briefly described and their bulk and mineral chemical compositions were also analyzed, as shown in Tables 1 and 2.