Romanian complex data center for dense seismic network

Abstract

In 2002, the National Institute for Earth Physics started the development of its own real-time digital seismic network. This now consists of 86 seismic stations, of which 32 are broad-band sensors, 52 stations are equipped with short-period sensors, and two seismic arrays, all of which transmit data in real time to the National Data Center (NDC) and the Eforie Nord (EFOR) seismic observatory. EFOR is the back-up for the NDC, and it is also a monitoring center for Black Sea tsunamis. The seismic stations are equipped with Quanterra Q330 and K2 digitizers, broad-band seismometers (STS2, CMG40T, CMG 3ESP, CMG3T) and Episensor Kinemetrics acceleration sensors (±2g). SeedLink is a part of Seiscomp2.5 and Antelope, which are the software packages used for data acquisition in real time and data exchange. Communication from the digital seismic stations to the NDC in Bucharest and EFOR is assured by five providers (GPRS, VPN, satellite, radio and internet). AntelopeTM 4.11 is used for acquisition and data processing at these two data centers for the reception and processing of the data, which runs on two workstations: one for real-time processing and the other for off-line processing. A Seiscomp 3 server works as the back-up for the Antelope 4.11. This acquisition and analysis systems for the seismic data produce information about the local and global parameters of earthquakes. In addition, Antelope is used for manual processing (e.g. association events, creation of a database, sending seismic bulletins, and calculation of magnitude and peak ground acceleration and velocity), generation of ShakeMap products, and interactions with global data centers. The NDC has developed tools to make all of this information easily available across the internet, and also to lay the grounds for a more modular and flexible development environment. This will enable centralizing of the data from software such as Antelope, which is using a dedicated database system (Datascope; a database system based on text files), to the more general-purpose database, MySQL. This acts like a hub between the different acquisition and analysis systems used at the NDC, while also providing better connectivity at no expense to security. Mirroring certain data to MySQL also allows the NDC to easily share information with the public, via the new application that is being developed, and also to mix in data collected from the public (e.g. information about the damage after an earthquake, which can be used to produce macroseismic intensity indices that are then stored in the database and also made available via the web application). For internal use, there is also a web application that uses the data stored in the database to display earthquake information, like location, magnitude and depth, in semi real time, thus aiding the personnel on duty. Another use for the data collected is to create and maintain contact lists to which the datacenter sends notifications (SMS and email), based on the parameters of an earthquake. For the future development, one of the NDC plans is to develop the means to cross-check the data generated between the different acquisition and analysis systems (e.g. comparing data generated by Antelope with data generated by Seiscomp).