@article{oai:ir.kagoshima-u.ac.jp:00015926,
 author = {江上, 椋也 and EGAMI, Ryoya and 高吉, 康平 and TAKAYOSHI, Kohei and 山本, 啓司 and YAMAMOTO, Hiroshi},
 journal = {鹿児島大学理学部紀要, Reports of the Faculty of Science, Kagoshima University},
 month = {Dec},
 note = {Dark spherical particles occur embedded in a fine- to medium-grained sandstone (feldspathic wacke) layer of the Late Cretaceous Saiki Subgroup of the Lower Shimanto Group in the Nishime area, southern Kyushu, and those have been investigated through a combination of techniques, including optical and scanning electron microscopy, electron probe microanalysis and Raman microscopy. The dark spherical particles are 10 to 50 μm across and look very much like “framboids”. The X-ray and Raman maps reveal that the dark spherical particles consist of iron oxide namely hematite. Therefore, the dark spherical particles should be identified as “framboidal hematite”. Previous studies proposed that the Fe-rich framboids represent replaced primary “framboidal pyrite”. However, we could not find framboidal pyrite in all of the samples investigated and there is no trace of iron sulfide in the framboidal hematite of this study. The results suggest that the framboidal hematite has not been replaced from pyrite but formed directly in the sandstone layer. The dark spherical particles of this study exhibit a newly found unique occurrence of framboidal hematite.},
 pages = {16--24},
 title = {九州南部北薩地域の下部四万十層群佐伯亜層群に産する暗色球状粒},
 volume = {54},
 year = {2021}
}