Lesson of the Japan Earthquake

1995/05/01 Nuñez-Betelu, Koldo Iturria: Elhuyar aldizkaria

• Geologia

Six-fold movements and tectonic activity are closely related and tectonic activity, although at different levels, occurs all over the world. Most earthquakes and more violent earthquakes occur in areas where the tectonic plates face each other. In the active volcanic regions, earthquakes are also frequent, being in most cases their local extension.

Currently, the largest seismic activity occurs in the vicinity of the Pacific Ocean, where the plate is moving rapidly, pushing the surrounding plates. That is why in many regions of East Asia and the American West there are frequent violent earthquakes. Faced with these earthquakes, in rich countries such as the US and Japan have costly programs to prevent earthquakes and to protect against earthquakes. In poor countries, however, little is done to prevent earthquakes.

Despite the measures taken, this year again an earthquake has caused terrible damage to Japan. The January earthquake has caused more than 5,000 people to lose their lives and more than 300,000 have lost their homes. Despite the fact that Japan is in a region of high seismic risk, the January earthquake surprised the inhabitants of the Kobe area for many reasons. On the one hand, in Kobe many years ago there were no major earthquakes and, on the other, other Japanese regions, such as the Tokyo area, are considered more dangerous. There are only secondary failures of the caves and in one of them arose the January earthquake, reaching a value of 6.9 on the Richter scale. It was very similar, both geologically and on a scale, the earthquake that occurred a year earlier in the California area of Los Angeles, but there were very few dead, despite the serious economic damage.

To reduce the consequences of earthquakes in Japan about 30 years ago, an early swimming programme of earthquakes was launched. This program focuses mainly on the seismology, but so far has given very few results. However, thanks to the research carried out in the framework of this program, interesting geological findings, such as that of the double seismic region of the Japanese coastal subduction zone, have also been carried out.

On the other hand, the government issued in 1980 measures to protect against earthquakes. Thus, it established special rules for new constructions and articulated training programs to the public. Thanks to these rules, some of Kobe's new constructions did not fall to the ground in the January earthquake, saving lives. But unfortunately not all these measures have been sufficient.

Looking ahead, both in Japan and in the rest of the countries, geologists and engineers will continue to investigate to minimize earthquake damage. However, due to unpredictable factors in any measure, earthquakes will always cause damage. And let us not forget that earthquakes can occur anywhere in the world, also in Euskal Herria. Therefore, both in construction and in our daily activities, we should take into account that our Earth is geologically alive.

In short, the price to be paid for living on a technically active planet, both by earthquakes and other geological phenomena. Another remedy would be to go live to the Moon, where we would surely be free from the earthquakes, but not from the bombardment of meteorites of all sizes, for which a umbrella has not yet been invented. However, to any extent, human beings will never be able, nor dominate the Nature of our Earth or of another planet, and we will always have to try to live with it in the greatest possible harmony.