Installation of new stations in the hydroacoustic monitoring network for the Comprehensive Nuclear-Test Ban Treaty

The International Monitoring System (IMS) is a global network of hydroacoustic, infrasonic, seismic and radionuclide sensors to detect, identify, and locate the signals generated by a nuclear explosion to verify compliance with the Comprehensive Nuclear-Test-Ban Treaty. The IMS hydroacoustic network, which monitors the major world oceans, contains eleven stations located with an emphasis on the vast ocean areas of the Southern Hemisphere. The two sensing techniques employed in the hydroacoustic network are hydrophone sensors, which effectively cover large ocean areas, but are quite complex and expensive, and seismic detectors on small islands which are less effective, but considerably simpler and cheaper. The establishment of the IMS network commenced in 1997. During the first two years, surveys were conducted at several station sites and contracts for the design and installation of the first stations were negotiated. The year 2000 has been a major milestone in the implementation of the hydroacoustic network. One new T-Phase station and two new hydrophone stations have recently commenced the transmission of real time data to the International Data Centre in Vienna, Austria. Both hydrophone stations were installed during February and March 2000 in the Indian Ocean; one at Crozet Islands, and the other one in the Chagos Archipelago, British Indian Ocean Territories. Although both stations were built to the same internationally agreed specifications, the design and installation techniques differed significantly. A careful assessment of the acoustic performance of these stations is in progress
Galindo M , Newton J .
International Monitoring System, hydroacoustic monitoring network