The Namba Formation in Osaka Plain is defined as the deposits after the Last Glacial Maximum stage. The gravel bed below the Namba Formation is called the Tenma Formation, deposited during the Last Glacial stage. But the stratigraphy on this gravel bed has not been demonstrated sufficiently with stratigraphic data. In this paper, the distribution of this gravel bed is investigated using many drilling data integrated in the Database for Information of Ground (DIG) constructed by the Geo-database Information Committee in Kansai. As a result of this study, the gravel bed 4-7 meters thick filling the buried valley along the Yodo, Ina, and Daini-Neya (Yamato) Rivers is correlated with the lowermost part of the Namba Formation deposited from 2ka to 1ka. The buried valley eroded from the alternate sand and gravel intercalating peat layer deposited during the Last Glacial stage to the Ma12 marine clay bed deposited during the Last Inter-glacial stage. The lower and middle parts of the Namba Formation conformably overlie the gravely lowermost part at the river mouth area of the Yodo River, while overlapping at the upstream area in the margin of the Osaka Plain. Additionally, the paleomorphologic feature of the Osaka Plain at 2ka is presented with the basal plane on the Namba Formation, including the lowermost part.

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To clarify the temporal and spatial distribution of industrial atmospheric pollutants, spheroidal carbonaceous particles (SCPs) produced by high-temperature combustion of fossil fuel in sediments have been examined. We examined two core sediment samples in Osaka City (the inner moat sediments around Osaka Castle and Nagaike Reservoir sediments), conducted concentration analysis and electron microscopic observations, and compared them with outer moat sediment results. The results of the analysis indicate that SCPs are detected in both of the core samples, and vertical variations of the SCPs concentrations are similar. The SCPs concentration increases upward gradually above the layer which has been dated to the 1950s, and the highest level is detected in the layer which has been identified to be the 1960s. In the uppermost sediments, SCPs exhibit convoluted and layered surface structure, indicating that their origin is oil combustion. It is considered that these vertical temporal trends correspond to the historical changes of SCPs emissions from fossil fuel combusted in power plants and other facilities around Osaka Bay.

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Concentrations of heavy metals (Pb, Cu, Zn, Ni and Cr) were measured from 131 samples in two sediment cores excavated from the outer and inner moats of Osaka Castle in Osaka, Japan. Temporal changes in the contaminations of heavy metals over 100 years provide valuable information about the history of heavy metal pollution in Osaka.
Concentrations of heavy metals (Pb, Cu and Zn) increased gradually from about 1900 and reached their maximum at about 1960, and after which they decreased to the present levels. This trend of heavy metal concentrations is similar to that in ponds near Osaka. The decrease of heavy metal concentrations from the 1960s was caused by the regulation of pollutants. The outer moat of Osaka Castle had adjoined the weapons factory known as the Osaka Artilleryman Factory from 1870 to 1945. This factory was one source of heavy metals in Osaka Castle's outer moat during this period. The outer moat is strongly influenced by anthropogenic discharges from the Osaka Artilleryman Factory.

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The Nobi Plain is located on the Pacific side of central Honshu Island, extending about 50km from north to south and 35km from east to west. The landforms of the plain can be divided into three units: alluvial fans, flood plain, and delta.
This paper aims to clarify the late Holocene depositional change and evolution of landforms in the Nobi Plain based on the development and distribution of archaeological sites, combined with the stratigraphy observed at their sites. The locations of archaeological sites can be grouped into three regions according to their ages. Changes in the distribution of the regions are summarized as follows; a) During 4, 300-3, 000yrs BP, archaeological sites were unevenly distributed in the northeast region, and no archaeological sites were found in the central and western part of the plain. b) After 3, 000yrs BP, locations of archaeological sites spread gradually to the west and central region. It can be concluded, therefore, that sedimentation area moved to the western and southern part of the plain. c) After 2, 200yrs BP, many archaeological sites were located in the central and south parts of the plain. The depositional area moved further west and south after that period.
These changes of sedimentary region correspond with a conspicuous increase in subsidence, according to the Nobi tilting tectonic movements.

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The author carried out research on the variations in the sedimentary environment of the late Pleistocene-Holocene deposits at Tokyo Port and the surroundings area in the Tokyo Bay, based on geological and geotechnical data. Changes in the sedimentary environment were clarified using facies analysis, engineering properties, diatom analysis, and age determination by radiocarbon dating for the latest Pleistocene-Holocene valley-fill deposits in the Paleo-Tokyo Valley, the Paleo-Kandagawa Valley, and the Paleo-Urayasu Valley. The three buried valleys were filled with the Nanagochi Formation, which is overlain by the Yurakucho Formation, although the sizes of the basins, river bed gradient, geology of the hinterland, and the thickness of the deposits are different.
The Nanagochi Formation and the Yurakucho Formation can be distinguished in the light of diatom analysis and engineering properties of the soil. The basal part of the Nanagochi Formation in the Paleo-Tokyo Valley is river gravel, and the middle to upper parts are sandy to muddy layers showing the facies of a river delta to brackish water environment. This formation was deposited rapidly between 15, 000 and 12, 000cal yrs BP. In the Paleo-Kandagawa Valley and the Paleo-Urayasu Valley, however, the basal horizon consists of sand and mud layers, and the upper horizon of the Nanagochi Formation consists of mud layers in the facies of brackish and marine water. The boundary between the Nanagochi Formation and the Yurakucho Formation is -45 to -50m A. S. L., corresponding to 12, 000 and 10, 000cal yrs BP. Changes in sedimentation rate and sedimentary facies around the boundary suggest temporal stagnation and minor lowering of sea level.
The Yurakucho Formation is composed of two zones, a lower zone characterized by sandy clay layers and an upper zone (a lower subzone of mud layers and an upper subzone of sand layers). On the basis of diatom analyses, the lower sandy clay layer of the Yurakucho Formation indicates environments of estuary to inner-bay in the stage of rapid transgression and enlargement of the bay between 10, 000 and 7, 000cal yrs BP. The dominant diatom species changes from Paralia sulcata of the lower to Thalassionema nitzschioides of the upper zones in a marine water environment. The ages of the boundary between the two zones may be about 6, 000 to 5, 000cal yrs BP. The mud layer (the lower subzone) of the Yurakucho Formation, showing the marine water facies, was deposited rapidly after the maximum transgression, between 5, 000 and 3, 000cal yrs BP. Since about 2, 000cal yrs BP, the upper sand layers (upper subzone) has shown advancement of a delta front in the east part of the Paleo-Urayasu Valley, where the deposits are characterized by the diatom assemblage of brackish to river water.

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