Global Marine helps install landmark seismic activity monitoring ‘Ocean Bottom Unit’
Asia is one of the world’s most active regions for natural disasters in the world. It experienced one of the devastating Tsunami in 2004 and on Boxing Day 2006 an offshore earthquake, measuring 7.2 on the Richter scale occurred in South East Asia. Two people lost their lives, 40 others were injured and the largest outage of telephone and Internet services in years. The quake damaged the fibre-optic cables which lay on the ocean floor south of Taiwan and facilitate communications between the mainland, Taiwan, Hong Kong, the US, Southeast Asia and Europe. Millions of people experienced severe disruption in accessing websites and international dialling facilities were also affected. Global Marine Systems immediately galvanised three of its cable ships to the affected region and it is working hard to prepare the cables and get Asia back online. To understand tsunamis, and their causes, seismic variances needs to be closely monitored and evaluated and this is another key area in which Global Marine Systems plays a role.
by GABRIEL RUHAN
In November 2006, the Korean Meteorological Association (KMA) commissioned the installation of a pioneering ‘Ocean Bottom Unit’ (OBU) 20km off the coast of Ulleungdo
(an island 135km east of the Korean peninsula) which acts as a “listening device” to detect and monitor high levels of seismic activity. Whilst not designed primarily as a tsunami early warning device the measuring of seismic activity will enable the KMA to better understand how this activity can lead to tsunamis, and how tsunamis work. Global marine experts KMA enlisted the help of KIT valley, providers of seismic monitoring systems, and SpaceTech, project managers of space and terrestrial systems. In turn, it contracted world leader in subsea cable technology Global Marine Systems Limited to install the OBU 2,000m below sea level along with the essential seismic cable connecting the OBU to the island. The fibre optic cable not only provides power to the OBU, but also transfers the crucial activity measurements back to the island. KIT Valley chose Global Marine Systems Limited as it is a leading provider of submarine cable installation and maintenance services and world-renowned for its specialisation in this area. KIT Valley was confident that its experience and expertise could ensure that the careful deployment of the cables would ensure optimal performance from the OBU. If successful, the project will pave the way towards the installation of up to five similar 33