The whole-rock chemical compositions of phosphatic and carbonate nodules occurring in the Neogene sedimentary rocks of the Miyazaki and Niigata Prefectures were determined. The Sr and P2O5 concentrations within these nodules were found to be strongly correlated, suggesting that Sr is exclusively accommodated in authigenic apatite. A similar correlation between Ba and P2O5 concentrations was also observed. The phosphatic nodules are evidently composed of initial clastic material with varying proportions of apatite. The Sr concentrations of apatite samples from the Miyazaki and Matsunoyama areas were 4934 and 1819ppm, respectively. The Sr/Ca ratios of these same apatite samples were 0.0057 and 0.0021, both of which are lower than the Sr/Ca ratio of 0.0089 found in seawater. This finding suggests that the Sr/Ca ratio in pore water originating from the sea was modified prior to apatite precipitation as the result of the dissolution of calcareous skeletons with various Sr concentrations.

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Three brachiopod species, Bathymyonia neimongolica (Wang and Zhang 2003), Neospirifer moosakhailensis (Davidson 1862), and Spiriferellina fredericksi sp. nov., are described from the lower Kamiyasse Formation (Wordian), Kamiyasse-Imo area, southern Kitakami Mountains (South Kitakami Belt), northeast Japan. All three species are antitropical brachiopods, distributed in the transitional zone between the Boreal-Tethyan realms, which includes north China (Inner Mongolia), northeast China (Heilongjiang and Jilin), eastern Russia (South Primorye), and northeast Japan (South Kitakami Belt). Palaeobiogeographical data on the three species, assigned here to the Kamiyasse-Imo fauna, suggest that the South Kitakami region was located immediately east of North China (Sino-Korea) in the middle Permian (Wordian).

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The GS-TK1 boring core is 145m depth drilled on the right bank of the Karasugawa River in Takasaki City, Gunma Pref. Japan. In previous view of stratigraphy of the GS-TK1, the deposits of 40-104.9m depth are the Middle Pleistocene. In reinvestigation of the GS-TK1 boring core, a new tephra bed Tk-16.6 was found at 16.57-17.0m depth. On the basis of the mineral compositions, refractive indices and fission-track dating, the Tk-16.6 tephra is correlated with a part of the APm Tephra Group, which is a well-known widespread tephra of the Middle Pleistocene in central part of Honshyu, Japan. Based on geological studies of tephras and lithofacies in the adjacent Iwanoya-Hill region, it is reasonable to think that the deposits of 13.5-104.9m depth of the GS-TK1 boring core are correlated with the Agatsuma-Loam and the Nodono Formation that are the Middle Pleistocene deposits.

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Reddish brown clastic beds associated with chert beds and greenstones were newly found in the Sumaizuku Unit of the Northern Chichibu Belt in the Kanto Mountains. These beds consist mainly of thick sandy mudstone beds containing thin conglomerate layers. Sandy mudstone beds are massive and structureless, while conglomerate layers are normally sorted. Mudstone and matrix of conglomerates are composed of microcrystalline quartz, finer grain of hematite, opaque minerals and radiolarian tests. Conglomerates consist mainly of subrounded granule of chert, siliceous mudstones, limestone and volcanic rocks accompanied with clasts of volcanic glass and sponge spicules. Therefore, sandy mudstone and conglomerate are lacking in terrigenous clastic particles. The modal composition of the clastic beds is quite similar to that of interbedded clastic beds in bedded cherts of the Mino Terrane that were redeposited in the open oceanic basin. However, reddish brown clastic beds are much thicker than clastic beds of the Mino Terrane, which suggests that they were deposited in hemipelagic area around a seamount situating near trench in the Early Jurassic.

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Living (stained) benthic foraminifers were found on the surface of paddy field in Minamisoma City, Fukushima Prefecture, Northeast Japan, in September 2012. Because those foraminifers were sampled about 18 months later since the 2011 off the Pacific coast of Tohoku Earthquake (the Tohoku earthquake), those were not individuals transported by tsunami. They should be reproduced and grew in that paddy field. Foraminiferal tests in tsunami sediments have been used for estimating origin of those sediments, because it have been interpreted that those tests were transported by tsunami. Present finding, however, suggests that tsunami sediments sometimes contain foraminifers grown in new environment occurred by tsunami.

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