International Data Centre records first event detection by three monitoring technologies
For the first time in the history of the Provisional Technical Secretariat, all three wave-energy monitoring technologies in the CTBT global verification regime have picked up signals from the same seismic event. A 7.3 magnitude earthquake in the Irian Jaya region of Indonesia, which happened at 10:50:20.59 (GMT) on 10 October 2002, was detected by over fifty stations, including numerous seismic stations, four hydroacoustic stations and one infrasound station. The International Data Centre of the CTBTO Preparatory Commission in Vienna, which receives data in near real time from the monitoring stations, was then able to locate the event. The Indonesian earthquake is the first instance where all three technologies have detected the same event and it highlights the significant advances which have been made in developing the capacities of the CTBT verification regime. Events generating a signal which can be recorded by all three technologies are very rare. The global verification regime is currently being established under the terms of the Comprehensive Nuclear-Test-Ban Treaty, and uses four complementary technologies to detect evidence of non-compliance with the Treaty. Three of the technologies - seismic, hydroacoustic and infrasound - can detect seismic events by identifying the shock wave energy as it travels through water, underground and in the atmosphere. The fourth technology seeks out specific radionuclide particles which point to a nuclear explosion. The verification regime must be operational before the Treaty enters into force. At present, approximately one third of the network has been established, and the detection capabilities of the system are improving all the time. While the primary purpose of the verification regime and the data it collects is to monitor compliance with the CTBT, the data has a host of potential civic and scientific applications, one of which could be to support research into earthquakes.