On the Scientific Research for the Improvement of the Environment of Cities on the Deltaic Areas

Abstract

Big cities in the world as follows, New York, Helsinki, San Paulo, Rio de Janeiro, Chicago etc., stand on the hard rocks, such as pre-Cambrian gneiss or Paleozoic formations.
On the contrary, many cities in Japan are situated on the deltaic areas with marine silt or silty clay. The land-sinking and the earthquake are their suffering subjects. Besides this, the soft ground constituting of volcanic clay also suffers many cities in our country.
The politicians in Japan should understand that it is the most efficient and appropriate investments for the future to pursue investigations in natural conditions on the deltaic areas.