Formative processes of conglomerates intercalated in interbedded siltstones and sandstones of the Upper Pliocene Shiramazu Formation in the southern Boso Peninsula were investigated. The study was based on detailed outcrop analyses of geometry, composition and shape of component clasts, and faunal features of the deposits. Conglomerates contain both articulated and fragmented Calyptogena shells in component siltstone clasts and scoriaceous muddy matrix, and were interpreted to be a debris flow deposit. However, the conglomerates show the following external and internal features : 1) the conglomerates show a locally developed anticlinal or dome-like structure compared with the associated interbedded siltstones and sandstones that exhibit monoclinal structure ; 2) most of component clasts show lithologies similar to those of interbedded siltstones and sandstones of the Shiramazu Formation ; 3) contacts between the conglomerates and the associate interbedded siltstones and sandstones are not sharp or erosional and are commonly transitional associated with brecciation of some parts of surrounding interbedded siltstones and sandstones due to injection of scoriaceous muddy matrix ; 4) locally, conglomerates show dyke-like and sill-like occurrence compared with the surrounding interbedded siltstones and sandstones ; 5) occurrence of Calyptogena shells shows a spectrum from articulated, through partly fragmented, to intensely fragmented condition due to the intensity of injection of scoriaceous muddy matrix ; 6) the geologic age of Calyptogenabearing siltstones (4.8-3.8 Ma) is older than that of the interbedded siltstones and sandstones of the Shiramazu Formation (3.4-2.55 Ma). These features of conglomerates are interpreted to indicate that they developed in response to hydraulic fracturing of some parts of the lower Shiramazu Formation with Calyptogena colony and intruded into interbedded siltstones and sandstones of the upper Shiramazu Formation as mud diapirs under overpressure in the landward slope of the paleo-Sagami Trough.

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Pliocene foraminifera and calcareous nannofossils from a borehole section "Kainosawa Onsen" in the eastern part of Akita City, Akita Prefecture, Japan Sea borderland of northern Japan were examined. The information on biostratigraphy and inferred paleoenvironment from the study section will furnish basis for further study on the Pliocene formations in the Sea of Japan region.The studied section is correlated to the uppermost part of the Onnagawa Formation or the lowermost part of the Funakawa Formation, Tentokuji Formation, and Sasaoka Formation, in ascending order.The Globorotalia ikebei/Orbulina universa Zone and the Globigerina pachyderma (dextral)/Globorotalia orientalis Zone were recognized as planktonic foraminiferal zones, the Miliammina echigoensis Zone and the Uvigerina akitaensis Zone were defined as benthic foraminiferal zones, and CN12a Subzone were recognized as calcareous nannofossil zone. From these fossil zones, a geologic age of Pliocene was elucidated for the Funakawa and the Tentokuji Formations.Assemblages of planktonic foraminifera in the Globorotalia ikebei/Orbulina universa Zone indicate a paleoenvironment with cold surface water whereas those in the G. orientalis/G. pachyderma (dextral) Zone indicate relatively warm surface water. Such assemblages suggestive of warm water are inferred to have been brought into the Sea of Japan by the influx of transitional surface water between the warm Kuroshio Current and the cold Oyashio Current.Upper Bathyal Zone or deeper paleobathymetric paleoenvironment is estimated for both the M. echigoensis Zone and the U. akitaensis Zone. Generally a paleoenvironment with cold water is assumed from the assemblages of these two zones. On the contrary, influx of relatively warm water is assumed from parts of the assemblages of the U. akitaensis Zone.Furthermore, fluctuations of primary productivity during the deposition of the studied interval were suggested by the analysis of microhabitat preferences of benthic foraminiferal assemblages.

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The Inumodorikyo Complex is a newly defined Jurassic accretionary complex within the Chichibu Terrane in the Ouchiyama area, eastern Kii Peninsula, Southwest Japan. The Inumodorikyo Complex consists of Toishi type siliceous claystone, chert, red muddy chert, red siliceous mudstone, dark green siliceous mudstone, and coarse clastic rocks. These rocks are bounded by series of faults striking ENE-WSW and dipping northward at various degrees. The Inumodorikyo Complex is tectonically characterized by imbricated structures which consist mostly of tectonic sheets bounded by faults. Chertclastics sequence is reconstructed by the lithofacies characteristics in combination with the radiolarian fossil content which indicates the Middle Triassic-late Middle Jurassic age.In the Kii Peninsula, the Chichibu Terrane is subdivided into the eastern and western parts. The Ouchiyama area is located at the central part of the eastern part of the Chichibu Terrane. The existence of the Kurosegawa Terrane mainly composed of Paleozoic complex in this area was a subject of debate. This study demonstrates that the Kurosegawa Terrane does not exist in the above-mentioned area, where the Chichibu Terrane composed of the Middle Jurassic accretionary complex is widely distributed.

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Biofilm was formed on the surface of culture solution using mining waste water, collected from Hirayu mine in Gifu Prefecture. Both optical and electron microscopy showed that numerous bacteria are involved in this biofilm. On the surface of the biofilm schwertmannite (Fe₈O₈(OH)₆SO₄) was identified using electron diffraction pattern (2.5 Å and 1.5 Å). The experimental observations revealed that the Fe-sulfate mineral was microbiologically formed for only 2 weeks. Atomic-force microscopy showed that the formation processes of the biofilm with submicron rugged structure on the primitive stage. Fe-sulfate biomineralization in mining waste water carries an important role in not only anaerobic condition but also oxydizing condition.

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Cathaya (Pinaceae) pollen was discovered from the Pliocene Koka Formation of the Kobiwako Group, Shiga Prefecture, Japan. The pollen morphology was examined with the light and scanning electron microscopes. The characteristics indicate that the bisaccate pollen is Cathaya. This discovery suggests that further study on the pollen flora of the Plio-Pleistocene Kobiwako Group will clarifythe disappearance process and horizon of Cathaya in the area with relation to the climate change.

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