| 摘要 |
PURPOSE:To reduce the shock in laying the apparatus on the seabed and to improve the precision of the laying location by combining plural ballasts the underwater weights and shapes of which are different from each other and by controlling the speed of submergence according to the depth of water. CONSTITUTION:The spherical container 2 for the seismometer is attached to the fixed bed 3, plural ballasts A-D the underwater weights and shapes of which are different from each other are fit on the lower side of the bed 3. When the submergence speed of the apparatus, weight of the ballast and shape factor of the ballast are v, w and f respectively, the formula vproportional w.f holds. When the ballasts are arranged to be broken in the order of A-D every time a ballast reaches a fixed depth of water, the submergence speed can be reduced as the water becomes deep. In this way, the observation apparatus can be reached the seabed without a shock to the apparatus, and it can be submerged at higher speed in the upper layer of the sea wherein the affection of the waves and tidal current can be disregarded in order to improve the precision of the laying location. |
