Avoiding Disasters by Interpreting Natural Landscapes

Hiroshi Yagi
Professor
Department of Education, Art and Science

▲Field devices for disaster study (range finder, GPS and clinometer)

Living in a Disaster Era

The 21st century is a disaster era. Large-scale earthquakes have occurred around the world, including Japan and some areas in Asia, since the Mid Niigata Prefecture Earthquake in 2004. People are prone to be conscious of building breakage from strong earthquakes, but an inland epicentral earthquake can cause a terrestrial disaster such as a landslide and an avalanche of earth and rocks ending with tragic results.

▲We contribute to "Active faults in urban areas," which is published by the Geospatial Information Authority of Japan.

Past Disasters Hidden in Landscapes Around Us

Active faults are distributed along the borders between mountains and basins, which have caused earthquakes at recurrent intervals of a few thousand years. As faulting repeatedly occurs along the same trace, an earthquake displacing the surface of the earth by only one to two meters is a small step, but the accumulated displacement forms a small hill or an incline after several tens of thousands of years. A large-scale landslide may occur along with an earthquake or localized downpour, creating a cliff, depression or pond on a mountain slope. We may unconsciously live, never thinking of the history of such familiar landscapes.