History

Objective Geological Properties Propagation Range Results
Place
1991 Foundation Survey Reclaimed ground. Silt-Clay layers on the sand foundation 50 - 200m Identification of the sand (1.7km/s)  and the clay (1.5km/s) layers by the elastic velocity speed difference.
Chiba, Japan
1991 Foundation Survey Mainly silt layer. Clay and Gas layers also exist.  50 - 150m An organic-gas layer which is accumulated in the lower part of the clay layer was confirmed.
Saitama, Japan
1993 Aquifer characterization Limestone and weathering mud, sandstone layer. The permeability of the limestone is approximately 0.1 cm/s.  50m

Identification of the limestone layer and weathering mudstone layer. The Biot velocity dispersion is confirmed in the limestone. Permeability of the limestone layer is computed.

Florida, USA
1994 Long-range propagation Experiment Limestone and weathering mud, sandstone layer. The permeability of the lime stone is approximately 0.1 cm/s.  400m The limestone layer and weathering mudstone layer are identified clearly.
Florida, USA
1994 Slag layer imaging survey Slag screen bank for reclaiming is built in the shallow water sea bottom where dredged sand and soft cohesive soil deposit over the diluvia hard clay layer. The clay layer is replaced by slag layer.  50m Identification of the hard clay, sand, soft clay and slag layers. The slag layer especially  was shown that the velocity speed indicates small value because of the air involving in the slag layer. 
Okayama, Japan
1995 Oil exploration Weathering mudstone. Oil and permanent gas exist in the sand layer. It is hard environment for elastic wave  propagation in this medium. 250m A propagation experiment was conducted.
Niigata, Japan
1996 Foundation Survey Soft clay layer with 30 to 50 m thickness deposits on the gravel bed. 50m The boundary position of the gravel bed was obtained.
Philippine
1997 Exploration of bypassed oil  In the thick shale,  sandstone exists. In the sandstone, oil and permanent gas exist. The dislocation and crack exist mostly. 100-150m Identification of the sandstone and shale. Also Gas layer location was obtained  by using attenuation imaging. Measurement within steel casing.
Trinidad and Tobago
1998 Soil Survey Fresh andesite, weathering andesite and gravel layer are alternate. A lot of crack exists in the weathering andesite layer.  40m Identification of the fresh andesite and gravel layer.
Kumamoto, Japan
1999 Aquifer characterization Limestone, weathering mudstone and sandstone layer are alternate. The Sand layer exists partly. Permeability of limestone is approximately 0.1 cm/s. 50m Limestone and weathering mudstone was identified. The obtained permeability is good agreement with the results depended on a pump test.
Florida, USA
1999 Soil Survey Sand layer with slant exists  partly deposit in the thick shale stone. There are many crack with directivity and high water permeability partly. 10-50m The velocity speed and attenuation images indicated a good correlation with situations such as a crack, weathering, etc. of foundations .
Gifu, Japan
1999 Soil Survey Sedimentary rock containing tuff, sandstone and gravel rock. 40m Identification of the gravel rock layer by attenuation imaging.
Aomori, Japan
2000 Soil Survey Weathering part of tuff-gravel rock and fresh part of tuff-gravel rock by 2 layers structure. Crack in the weathering part is not significant while crack in the fresh part induces high-permeability. 20-50m Attenuation distribution well indicated the weathering part and fresh part. Moreover, high permeability zone indicated an appropriate relation with a historical data.
Tochigi, Japan