Jump to Main content area

 

Observation network


Broadband seismic observation network

Since the establishment of the first broadband seismograph by the Institute of Earth Sciences, Academia Sinica in 1992, CWB started in to set up broadband seismic monitoring stations to work with the broadband stations already established by Academia Sinica and the National Central University after joining in the “Research on Earthquake and Active Fault Program” of the National Science Committee in 2000. At present, there is a total of 35 stations with 10 broadband ones of them being installed with accelerometer to compensate for the record loss in case of nearby earthquake and relatively strong earthquake. The broadband permanent stations have been gradually set up to enable the broadband monitoring stations in Taiwan to improve both in density and evenness to achieve the expected goals of quick prediction as well as meet the double requirements of “Minor Quake Monitored, Major Quake Measured”. In addition, the records of seismic wave of long distance large scale earthquake across the world can be covered to effectively improve the seismic monitoring of the adjacent regions of Taiwan and the world. Starting from 2007, broadband seismographs have been placed in well in Hsinchu, Chenggung, and Yungkang, improving the quality of seismic signals by placing the broadband seismic monitoring instruments in deep wells. The broadband seismographs placed in deep wells can effectively prevent the noisy of the ground surface and improve the visibility of the natural seismic information. Thus, deep well seismographs are expected to increase year by year to make signals clear in each station.

Broadband seismic observation network

The broadband seismic observation network established by CWB, the broadband seismic observation network of Institute of Earth Sciences, Academia Sinica and the National Central University Broadband Station are integrated as 'Broadband Array in Taiwan for Seismology (BATS)' (including 32 CWB broadband ground stations, 3 deep-well stations, and 21 broadband stations of IESAS in a total of 56 stations at present). The data collected by such stations are transmitted by digital network cable of Chunghwa Telecom back to CWB broadband data processing center. The collected seismic data are exchanged and processed in real time for information sharing. The management of the National Central University Broadband Stations (6) has been transferred to CWB by the end of 2003.

As the recording band of the broadband seismograph is relatively broad and the sensors are relatively sensitive, it can fully record the seismic wave pattern and it is more accurate in earthquake locating and scope calculation as well as make up the inadequacy and insufficiency of the seismic wave recorded by the traditional velocity and acceleration types of seismographs. The seismic wave records of the cracking process of the complete fault can better help understand the relativity between the plate tectonics of Taiwan as well as its neighboring regions and seismic activities.