A reformed calculation method of paleotidal current velocity is proposed. Paleotidal current velocities can be estimated using critical shear velocities for the threshold of sediment movement, the ripple-dune transition and the dune-plane bed transition. Depth-mean velocities were calculated by means of constituent grain size and bedform type for a cross-stratifications in the Upper Pleistocene tidal channel deposits exposed at Uchijuku, Ibarkai. The cross-stratification whose bedform type was dunes with ripples and reactivation surfaces contains features recognized as due to individual flood, ebb and slack-water events. The paleotidal speeds were between 44 to 50cm/sec for dominant flood currents, and 24 to 44cm/sec for subordinate ebb currents during neap tide. The velocity of spring flood tide was approximately 53cm/sec.

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Heavy mineral analyses were made for 18 samples of marine surface sediments in the Osumi Strait, south of Kyushu, Japan. Hypersthene is the most abundant, common hornblende, augite and olivine are next among the non-opaque minerals. The amount of heavy minerals is rich in the southwestern part of the Strait. There is a tendency to decrease in the total amount of heavy minerals and in specific gravity of bulk sediments northeastward. Surface sediments tend to become finer in the same direction. The current velocity necessary to move the sediment grain is changed with the specific gravity at the same grain size, because the grains with higher specific gravity are less mobile than the grains with lower specific gravity. It is considered that the grains are transported to the direction toward which the sediments become lighter in specific gravity and finer in grain size. Therefore, surface sediments distributed in the Osumi Strait are moved from southwest to northeast. This direction is concordant with the dominant current direction in the Strait. This means that the sediments are transported by the ocean current, the Osumi Branch Current, one of the branches of the Kuroshio flowing through the Strait and that the sediment distribution is highly influenced by the current.

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This paper is written about the sedimentological aspect of the seaside reclaimed land. The reclaimed land can be defined geologically as follows:
1) The reclaimed soil layers are a kind of sediments which belong to the newest geological age.
2) The reclaimed land consists of soil layers which human beings made consciously.
And the sedimentological definition of the reclaimed land can be given as follows:
1) The reclaimed area offers a space in which geological formations or layers are depositted.
2) The area is a kind of sedimentological testing field.
3) The reclaimed soil layers are filled with the heights of more than five meters above sealevel.
4) Those reclaimed deposits have been formed in the extremely short time.
Many reclaimed-lands have some geotechnical problems, which derive from four typical characteristics of the reclaimed land. Those characteristics are as follows:
1) Most reclaimed lands are formed as weak ground.
2) Most reclaimed layers consist of various kind of materials.
3) Most reclaimed deposits are usually very loose.
4) Groundwater level in the seaside reclaimed ground makes it a rule to be very high.
Considering above-mentioned difinitions and problems, the reclaimed land or ground should be studied hereafter from the viewpoint of sedimentology and geology.

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