Geohazards

The result indicates that the radon-related radiation exposure is insignificant for short-term visitors but may reach ~1.8 mSv a-1 for tour guides and ~25 mSv a-1 for cave utility workers. The latter values exceed the IAEA-recommended safety threshold of 1 mSv a-1 (IAEA, 1996). We recommend radiation monitoring for cave utility workers and tour guides. Prolonged human presence in Rong Cave should be avoided during periods of seasonally elevated radon concentrations.

11p meolep1 28-11-2018 19 0   Download

In recent years, after renovation policy launched by the Vietnamese government, the economy of Kien An - Do Son, Hai Phong coastal zone in the Northern Vietnam has quickly changed with high income and fast economical grow rate. With the economical development, the environment in many areas has been severely damaged. In addition, the so called "global change" has also strengthened the natural hazards especially torpedo, storms surges, salt intrusion due to the sea level change... increasing of the losses caused by natural hazards in this very sensitive zone.

12p dem_thanh 22-12-2012 41 2   Download

The NW of Vietnam is currently affected by a stress field characterizing by approximatc1y NS and EW sub-horizontal maximum and minimum principal stress axis respective1y. The results obtained from field investigations and numeric modelisation reveal that the present stress field varies not only in relative magnitude but also in orientation of principal stress axes from point to point and in depth. The tectonic stress variation strong1y depends on the geometry and active kinematics of faults as well as on their earthquake history. ...

8p dem_thanh 22-12-2012 40 3   Download