The topography around the trench-trench-trench triple junction off the Kanto Plain and Neogene tectonic evolution of the Japanese Island Arcs have been examined. The most important factors for the tectonics are the deformations of the subductive boundary around the triple junction for retention of the minimum curvature of subduction of the thick Pacific Plate along an irregular boundary with an uncinate process, created by the retreat of the Izu Trench on the Philippine Sea Plate. The Great Bend of the zonal structure in central Japan, the east-west compressional stress field in the Southwest Japan, and the tectonic evolution of northeast Honshu can be systematically explained with the deformations.

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Laser ranging has been carried out from the Crustal Activity Observatory of Shizuoka University in the Udo Hills (105.83 m in altitude) to the Advertising Tower of Tokai University on Yatsuyama Hill (108 m in altitude and 3708.568 m from the Crustal Activity Observatory) and the Microwave Relay Antenna of NTT on Yambara Hill (448 m in altitude and 10552.989 m from the Crustal Activity Observatory). The ranging was done 4 times for intervals of 24 hours of continuous manual measurements in April and May 1995,and automatic measurements at 10 minute intervals from January to March 1996. Autoranger JX, manufactured by Rokuoh Precision, Inc., was used for the laser ranging.
The average distance and standard deviation was obtained for the set of 10 measurements. The confidence limits of 67% for the average distance, Ds, are 1 ± 0.8 mm. The meteorologic correction to obtain the real distance, D, from the measured distance, Ds, is formulated as follows.
D = DS + DS × (310.0 − (106.339 × P − 15.026 × E)/(273.15 + T)) × 10⁻⁶
where, P, E and T are air pressure in mmHg, vapor pressure of air in mmHg, and air temperature in ℃, respectively. The corrections for temperature, pressure and humidity are 4 mm/℃, 1.4 mm/10 mmHg and 0.3 mm/10%, respectively. The meterologic correction should be done on the laser path in the sky. The correction for vapor pressure is not significant compared with the confidence limits of ranging, and the pressure on the laser path can be estimated with sufficient accuracy from the pressure measured on the surface. However, it is difficult to estimate the temperature on the laser path with an accuracy better than 0.2℃.
If the real distance D does not change, the temperature on the laser path Tc can be calculate from the laser ranging distance, Ds, and the air pressure and vapor pressure measured on the surface using following equation:
Tc = (106.339 × P-15.026 × E)/(310.0 + (Ds-D) × 10⁶/Ds) − 273.15
The calculated temperatures Tc from laser ranging, air pressure and vapor pressure measured at the Shizuoka Meteorological Observatory of the Japan Meteorological Agency were compared with the air temperature measured at the Shizuoka Meteological Observatory. Stratification of the air column by solar radiation during day time and surficial cooling by radiation at night time were observed. Heat haze by surface heating from solar radiation was detected by the apparent cooler temperature of the laser path corresponding to a longer laser path and large standard deviation of the calculated temperature.
Laser ranging is thus a useful tool not only to detect crustal movement but also to measure air temperature on the laser path with an accuracy better than 0.2℃.

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The relationships among sedimentary texture, suspended sediment concentration, and benthic community were analyzed from shallow subtidal environments at Hamana Bay, Japan. Meiofaunal communities of the upper centimeter of the bottom sediment are dominated by nematodes and harpactacoid copepods; iuvenile gastropods and bivalves, ostracodes, and tardigrads are locally abundant. Sessile and slow-moving mobile macrofauna of the top few centimeters of bottom sediment are dominated by polychaetes and the gastropod Umbonium moniliferum, all of which are quite variable in distribution. Both macrofaunal and meiofaunal community composition are moderately correlated with sedimentary texture and depth. Sediment in all locations analyzed was fine to medium sand, with mud concentrations less than 3% of the sample by weight.
Suspended sediment concentrations (SSC) varied over two orders of magnitude, from 3.7 to 152.5 mg/l. SSC does not correlate statistically significantly with any individual variablc, but is best related to biotic components such as nematode abundance and mobile macrofaunal abundance. There is a relatively strong relationship between SSC and the first axes of principal components analyses of the biotic assemblages and the sedimentary textural properties, even independent of current conditions at the time of collection. That is, a linear combination of the biotic and sedimentary variables representing a high percentage of variability in the data provides the best predictor of SSC. Generally, samples with few mobile epifauna, large numbers of polychaete tubes, and large numbers of nematodes (which may produce large quantities of organic exudates) are associated with lower SSC, while the highest SSC values are found in areas with relatively large numbers of mobile macrobenthos.

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The concentrations of copper organic compounds dissolved in sea water in the westcrn North Pacific, Indian and Southern Ocean were determined from the collection of XAD-2 resin followed by atomic absorption spectrophotometry. The average concentration of total copper dissolved in surface water is 0.5 µgl⁻¹ for the western North Pacific, 0.7 µgl⁻¹ for the Indian Ocean and 1.3 µgl⁻¹ for the Southern Ocean, respectivly; 60 to 90 % of this copper is organically bound. Most of the copper organic compounds are involved in neutral or basic organic compounds with a molecular size ranging from 2 × 10³ to 2 × 10⁴. The intimate correlation between the organically bound copper and the combined amino acids adsorbed on the XAD-2 resin indicate that the organic ligand to the copper organic compounds might be polymer organic matter. The composition of the amino of the metal organic compounds suggests that few species of amino acids are concerned with metal complexation. These amino acids are not free but in a combined states, in polypeptides or polynucleotides accompanied with carbohydrates.

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Metamorphic rocks (consisting of anorthositic rocks and pelitic, basic and quartzfeldspathic gneisses) and igneous rock reference samples of the Geological Survey of Japan (GSJ) were decomposed with mixed acids by the method of Crock and Severson. The basic and quartz-feldspathic gneisses and the GSJ igneous rock reference samples totally dissolved, but the anorthositic rocks and pelitic gneisses commonly left residues.
To get a clear solution of these rocks, Crock and Severson’s method was modified : better results were obtained by repeated drying of the residues by adding a mixed solution of HCI and HCIO₄,with a little more water in the process of the expulsion of residual fluorine, instead of HCIO₄ and water.
The contents of Al, Fe, Mg, Ca, Ti, Mn and P in the metamorphic rocks and the GSJ igncous rock reference samples were determined by means of an inductively coupled argon plasma/optical emission spectrophotometer, and the Na and K contents by atomic absorption spectrometry.
The results of chemical analyses for the metamorphic rocks and JGS igneous rock reference samples decomposed by the modified method show the following things : the anorthositic rocks and pelitic gneisses show an increase of about 1–4 percent in the total amount of element oxides and about 4–9 percent in its increased total yield; the other rocks, especially the basic gneisses and basalts, tend to show a small increase in their total amount of elemental material, compared with those decomposed by Crock and Severson’s method.

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A new inlet system which will be able to be automatically controlled by a computer was developed for the MAT 250 mass spectrometer at Shizuoka University. The new vacuum line was basically combined by air-actuated vacuum valves with stainless steel tube connection attached to a glass diffusion pump, new desiccation traps including the Horibe Trap, a sample reservoir pumped up by mercury, and a carbonate reaction vessel. All the stop valves can be operated by compressed air of about 3.75 atm. Air supply to the valves is controlled by computer programming.

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