Annual and monthly water discharges and sediment discharges of the Huanghe River for 40 years from 1950 to 1989, and sediment budget of the Huanghe River are reviewed in this paper.
Average annual water dischage and sediment discharge of the Huanghe River for 40 years are 4×10¹⁰m³ and 1×10⁹ tons, respectively, at Lijin station. Both discharges come mainly during the period from August to November.. About 85% of sediment discharge comes in this period. For the great variability of the rainfall of the drainage basin of the river, the variability of the sediment discharge is great. The highest annual sediment discharge is about 20 times than the lowest one.
About 20-30% of the sediments passing the Lijin station is deposited on the subaerial delta plain of the Huanghe River, and 40-50% in the nearshore areas of the delta within about 30km from the coastline. A total of 70-80% of the sediments is deposited in the delta area and 20-30% of the rest is transported to offshore areas. In the Bohai Sea and the Yellow Sea, 10-15% and 15-20% of the sediments are deposited respectively, and less than 1% on the East China Sea shelf.

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The Otari-Sasagamine area is located in the westernmost part of the northern Fossa Magna, central Japan. The Neogene system in the area is mainly composed of turbidites and their associated deposits. The Neogene system in this area has been sedimentologically divided into two isolated depositional systems, that is, into the Otari system of the southwestern part and the Sasagamine system of the northeastern part. In this report, an attempt was made to clarifiy the petro-provenance of the Miocene formations, based on sandstone petrography, especially on the chemical composition of heavy minerals.
Petrographic studies of clastics were made mainly by examining chemical compositor of clino-pyroxene and garnet grains included in these sandstones. The reasonable difference for framework mode of sandstones between these two systems is not recognized. The heavy mineral composition and chemical composition of heavy minerals, however, show that they have been derived from different provenances. As a result, the petro-provenance of the sediments in the Otari area was found to be the Hida, Hida Marginal and Mino Belts to the west and southwest, and one of the Sasagamine area to be the Mino, Ryoke, and Sanbagawa Belts to the south. The gabbroic massif in the Hida Marginal Belt was appeared on the ground and supplied the detritus only to the Otari system at the depositional stage of the late Upper Miocene sequence.

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Four sequences of bedded red cherts of the Permian to the Jurassic ages from Ie and Izena Islands were chosen and studied to investigate whether these sequences were formed in deep waters of pelagic environments. Among the four sequences, the bedded red chert sequence in Mt. Gusuku (Tacchu) shows true pelagic features where unicolored and thinly bedded red cherts of the Late Triassic to the Late Jurassic ages are exposed as thickly as about 70m. The other three sequences are slightly mixed with bedded gray cherts and do not show true pelagic facies. Two sequences were identified as turbidites. 64 rock samples were systematically sampled from these four sequences and geochemically analyzed for their major and trace element concentrations in the bulk fraction as well as in the carbonate fraction. Chemical stratigraphy of the red cherts in Tacchu indicated systematic downward increases of major and trace metallic elements, suggesting plate drifting toward the equator from the southern hemisphere during the Late Triassic through the Late Jurassic. The degree of correlation between Fe and Mg in the noncalcareous fraction or among other major elements indicates that the bedded red cherts in Tacchu were truely deposited in the pelagic deep-sea environments, whereas other three sequences studied in Ie and Izena Islands were deposited in hemipelagic environments.

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Gammer-ray method for measuring wet bulk density of sediments is very useful for determining a thin turbidite layer. Although the value itself is not a true value, it is very useful for determining the relative change of the density. Because the density is controlled by sedimentary processes such as grain-size, specific gravity of grains, grain fabric and sedimentation rate, it recorded the physical processes of the sediment formation. Using the measurements, it is very useful to get many data for sedimentological analysis of sediments.

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