Host: Japan Association of Mineralogical Sciences
As for the building stones used for the stone-wall of the Kami-no-hashi Gateway of Fukuoka Castle, so many granitic rocks and subsequent dioritic to gabbroic plutonic rocks were used. Most of the granitic rocks were mostly hornblende-biotite granodiorite to adamellite, on the other hand, the dioritic to gabbroic plutonic rocks were almost grouped into hornblende quartz diorite. Major element compositions of the plutonic rocks were coincident with those of the Shikanoshima granodiorites and Shikanoshima basic rocks. Since the stone-wall of the Kami-no-hashi Gateway were also built from alkali basalt and serpentinite which were found around the Hakata Bay area as well as the plutonic rocks, the building stones of the wall were probably provided from the Miyanoura on Itoshima Peninsula and Shikanoshima Island, and supplemented by various rocks from neighbor areas at the northern Hakata Bay.
