Two piston cores collected from the Shichitou-Iwojima ridge area have been studied from mineralogical and geochemical points of view by means of X-ray diffraction (XRD), analytical transmission electron microscopy (ATEM), and X-ray fluorescence (XRF). XRD analysis shows that illite and chlorite are the major clay minerals, whereas smectite and kaolinite are small amount of the clay mineral assemblage except some tuff layers. The vertical homogeneity in clay mineral composition and the morphology and chemistry of clay minerals suggest that clay minerals in the present cores are detrital origin. However, the saponite contained in core St. 16 tends to be more abundant than that in core St. 19. Most of the saponite contained in core St. 16 was transported from volcanic province on land but some may have been transported from the neighbouring ridge and formed in situ-submarine. In this case the saponite was transported by the currents or water masses except the Kuroshio ocean current. The composition of clay-sized minerals is 64% clay minerals versus 36% non-clay minerals in core St. 16 and 63% clay minerals versus 37% non-clay minerals in core St. 19, respectively. Geochemical parameters showed that the influences of clastic minerals and the biological carbonate calcium were strong in the lower part (deeper than 130cm from the top of the core, >25Ka), particularly in the lowest part of core St. 16, whereas the influence of clastic minerals tended to decrease toward the upper part and the biological carbonate calcium showed an opposite trend. Geochemical parameters of core St. 19 exhibited a positive relationship between the intensity of the organic material productivity and clastic minerals around 14 Ka and the intensity tended to decrease toward the younger age. The authors pointed out that the variability of wind activity and biological productivity during the past 25, 000 years was attributed to climatic change.

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Sequence stratigrafic analysis of the subsurface Pleistocene successons in the central Kanto Plain, which has been subsiding since the Neogene, reveals characteristics of depositional sequences in an intensely subsiding area.
Seven depositional sequences are recognized in the shallow subsurface Pleistocene successions in the central Kanto Plain by observation of three cores at Kawaguchi, Kasukabe, and Noda, 90-110 meters in length. Depositional sequences near the ground surface are composed mostly of non-marine facies, whereas depositional sequences below them consist mainly of marine facies formed by a barrier island system. Particularly, the latter depositional sequences are characterized by the presence of bay ravinement surfaces and thick lagoon facies overlain by ravinement surfaces. According to the elevations of ravinement surfaces and bay ravinement surfaces in each boring site, it is obvious that the study area has been subsiding and Kasukabe district is situated in the central part of the subsiding area. Moreover, thickness of the lagoon facies is maximum at Kasukabe. Therefore, the formation of the depositional sequences with a bay ravinement surface and a thick lagoon facies is considered to have been intensely influenced by tectonic subsidence.

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The sea-marginal transition zone of the Mahanadi delta is a significant geomorphic belt running parallel and adjacent to the present-day shoreline. The various geomorphic features of this zone are of marine, fluviomarine and eolian origin. Within this zone, three subregions are differentiated:(1) the southwestern part in which the vast stretch of land is characterized by extensive coastal sand bodies along with an eolian dune cover;(2) the middle part characterized by numerous, discontinuous and parallel to subparallel series of ancient beach ridges separated by tidal flats or swamps;(3) the northeastern part dominated by tidal flats and mangrove swamps.
Prevalent wind has played a significant role in the differential development of geomorphic features, which reflect principal agents at work. In the southwestern part, the shore stretches against the prevalent wind direction, and wave and eolian processes are dominated to form stacked beach ridges covered by extensive eolian dunes. The shoreline trend in the middle part is almost parallel to the wind direction, giving rise to strong longshore currents which, combined with waves, form linear sand bodies parallel to the shoreline. The northeastern part is shadowed from prevalent winds. Wave and longshore processes are minimal there, and the extensive tidal flats and swamps are developed.

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This study addresses the identification of reliable paleocurrent indices that can be used to complement clast fabric data. Downstream variation in particle size, roundness, lithology and form were examined together with clast orientation in the gravel deposits of the Mitoyo Group, southwest Japan. Although maximum particle size and roundness do not show systematic downstream variation in the braidplain deposit of the Saita Formation, these parameters do show subtle downfan variation in the alluvial fan deposit of the Yakeo Formation. Particle lithology and form show random downstream variation in both formations. These observations suggest that maximum particle size and roundness may be helpful parameters to complement clast fabric data, especially for a small-scale alluvial fan deposit. Particle lithology and form are considered unreliable parameters in paleocurrent interpretation.

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Sedimentary conditions in glacier-fed Lake Pukaki (20km long, 5km wide, and 98.0m deep at maximum), New Zealand were examined in the glacier-melt season of 1998. Spatial distributions of water temperature and suspended sediment concentration (SSC) obtained by a TTD (temperature-turbidity-depth) profiler indicate that sediment-laden underflow initiated near the river mouths is relatively weak because of their vertical low SSC on the gentle slope, and that the underflow is bifurcated into suspension interflow and other underflow at midlake ca. 1500m distant from the river mouths. The continuous measurement of water temperature at some depths revealed that at midlake, the suspension interflow and underflow continuously occur about one day at least.

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