Accretion of the Aravalli volcaniclastic and chemogenic sediments and the igneous suite along the northwestern margin of the Indian Peninsular Shield, represents an excellent example of Lower Proterozoic rift tectonics and sedimentation. The entire sequence of Aravalli sedimentary rocks in both the deep sea and the shelf environments accumulated in several stages evolved through tectonic movements associated with the rifting in this part of the globe. The basement got cracked as a result of tensional tectonic setting and a number of curvilinear faults, pouring basic lava from the mantle plumes, were produced. In the type locality of the Aravalli Supergroup around Udaipur City, a fault-controlled trough acquired the shape of an epicontinental sea in which shelf sediments deposited. The interplay of tectonism and sedimentation continued till the entire basin was completely filled up by sediments and fluvial conditions evolved in its place.

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The study area is situated at the southern part of the Northern Fossa Magna region and is underlain by Miocene to Early Pliocene sedimentary rocks. The Miocene rocks are divided into the Aoki and Ogawa Formations. Lower Pliocene is newly named the Ashinojiri Formation. Aoki Formation is mainly composed of mudstone and sandstone. Ogawa and Ashinojiri Formations are mainly composed of sandstone and conglomerate. Ogawa Formation interbedded with acidic tuff layer (Koso Tuff) which can make a useful key bed of this area.
These formations are divided into ten sedimentary facies. On the basis of the facies analysis, they were deposited at the slope, shelf and nearshore environments, and also they formed a fan delta system. The fan delta system consists of the progradational stage and aggradational stage. The fan delta prograded to the basin and coarse materials were deposited on the slope in the progradational stage. While in the aggradational stage, the coarse materials were deposited on the shelf. The slope prograded during the progradational stage, and the shelf was filled up by aggradation of sediments.

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HCS (hummocky cross-stratification) mimics were discovered from Pleistocene tidal deposits (Shimosa Group) and fluvial flood deposits (Osaka Group). They closely resemble to HCS, except their small scale. These deposits indicate that waves are not likely mechanisms for the formation. Based on the facies and environmental setting, the HCS mimics were formed as three-dimensional antidunes with high suspended load. The discover of HCS mimics gave a new interpretation to the mechanisms of HCS formation.

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Several processes involved in dispersion and sedimentation of land-derived reddish soils were studied in the Okkubi River estuary on the Okinawa Island, Japan. The objective of this study was to investigate methods to prevent soil pollution of coral reefs. A mooring system equipped with two turbidity meters, two sediment traps, a current meter, and a depth recorder was maintained off coral reefs in 25m of water. Measurements were made during two different seasons: dry season (June 25 through July 17, 1991) and wet season (October 16 through November 3, 1991). Time-series data indicate inflows of terrigenous mud after precipitation; inflowing mulls flux from surface to bottom layers. The data also suggest resuspension of bottom sediments from the bottom to the surface layers more than 15m high. Resuspended sediments were silty clay, judged from the trapped sediment samples; muddy fractions contained in bottom calcareous sands may be mainly resuspended in a higher distance. Resuspension of bottom sediments is found to occur at the ebbing tide, when bottom tidal currents are stronger. Comparing mean turbidity (ppm) during the mooring observations with the flux rate of trapped sediments, the bottom layer show very higher mean turbidity than the surface layer, with respect to flux rates between the two layers. This may indicate difference in modes of sedimentation between bottom and surface layers; bottom layer turbidity represents many upward resuspensions, although these resuspended sediments cannot be effectively trapped by the sediment traps. Similarly organic matter rich samples indicate higher turbidity with respect to their flux rates by sediment traps. Sedimentation of fine-grained soils in the estuary should be studied more precisely using this mooring system to prevent the adjacent coral reefs from the outflowing pollution of reddish soils.

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The Daedong Group distributed in eastern part of Chungnam Coalfield consists of Hajo, Amisan, Jogyeri, Baegunsa, Seongjuri Formation in ascending order. By the paleontological study focused on plant fossils, the floral assemblages is undoubtedly a member of Dictyophyllum-Clathropteris Floristic Province in East Asia and belongs to its Southeasthern Subprovince. The geological age of the Amisan Formation, is obviously Late Triassic. This kind of view is also supported by the co-existing conchostracans indicating Late Triassic age (Norian). And other formations can be extended to the Early Jurassic by the composition of the flora.
Sedimentary petrological study focused on the sandstones by using the method of mineral assemblage, heavy mineral and quantitative analysis of tourmaline and garnet. The clasts of conglomerates of the Hajo Formation comprise 55% of schist which supposed to be derived from the preexisted Precambrian metamorphic rocks. Major mineral constituent of sandstones is quartz, occupying 61.5% of the total mineral assemblage. Average content of feldspar is 15% which is noticeably high amount than that of the Daedong Group in other areas. Sandstones of the Hajo Formation. and the part of Amisan Formation are classified as quartzose arenite and sandstones from the other formations are classified as feldspathic arenite/wacke. Heavy mineral constituents of sandstones are zircon, tourmaline, rutile, monazite, allanite, garnet, sphene, amphibole, chlorite, biotite and muscovite, and opaque minerals are composed of hematite, magnetite, calcopyrite, ilmenite and chromite. Quantitative analysis of the tourmaline by EPMA indicates that source rock of the tourmaline is Li-poor granitoid, aplite and Ca-poor metapellite or metapsammite. Garnets indicate the source rock as medium to high grade Ca-poor metamorphic rocks. The results of conglomerates, mineral assemblage and heavy mineral of sandstones suggested that the provenance of the Daedong Group comprised mainly quartzose rocks, and additional igneous and metamorphic rocks.

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Mineral assemblages pelites of sandstones support the stratigraphic division of the Pyeongan Group. In the Upper Member of Gobangsan Formation, sandstones are characterized by acidic volcanic rock fragments (17% on average of total constituents). The Nogam Formation contains abundant potash feldspar ranging from 2 to 22% (11% on average). The Hongjeom, and Sadong Formations and the Lower and Middle Members of the Gobangsan Formation comprise quartzose arenite/wacke. The result of heavy mineral constituents are coincident with the results of mineral assemblages of the sandstones of Pyeongan Group in differentiating the stratigraphic division. Tourmalines in the Pyeongan Group were derived from Li-poor granitoids, pegmatites and aplites, or Ca-poor metapelite and metapsammites. The garnets in the Nogam Formation were derived from medium- to high-grade metamorphic rocks.
The provenance of sandstones in the Hongjeom Formation, Sadong Formation, and in the Lower and Middle Members of Gobangsan Formation is supposed to be mainly quartzite and quartzose sandstone. The provenance of sandstones in the Upper Member of Gobangsan Formation was probably andesite and granodiorite which could supply plagioclase and acidic volcanic rocks as well as quartzite and quartzose sandstone. The provenance of sandstones in the Nogam Formation was granite, granitic gneiss, pegmatite and amphibolite which supplied potash feldspar as well as quartzite and quartzose sandstone.

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