RTQUAKE, A Real-Time Earthquake Detection System Integrated with SEISAN

Seismic networks have over the last 10–15 years become nearly exclusively real‐time networks. The software used for data collection is both commercial and largely public domain. The two main public domain real‐time detection systems are Earth Worm (EW; Johnson et al. , 1995; http://www.earthwormcentral.org; last accessed March 2014) and SeisComP3 (SC3; www.seiscomp3.org). Both systems receive data in real time, perform triggering, store data in a continuous manner, and automatically determine location and magnitude. For a comparison and evaluation of the two systems, see Olivieri and Clinton (2012). EW and SC3 read data sources using different communication protocols. However, the SeedLink protocol for data exchange, used with SC3, has more or less become the public domain standard for real‐time data transmission due to its simplicity and reliability, and many instrument manufacturers now offer SeedLink as a standard for their seismic field stations. Although both systems provide some degree of automatic processing (SC3 has rather sophisticated automatic location and magnitude ability), most seismic networks would want to do manual processing of some or all of the detected events. Many users transfer the data to the SEISAN processing system (Havskov and Ottemoller, 1999). SEISAN is probably one of the most complete and widely used public domain processing systems available. In 2011, 27% of the agencies reporting to the ISC used SEISAN and reported in SEISAN format (Dmitry Storchak, personal comm., 2011). SEISAN can also work directly with the SC3 archive making this a simple way to inspect, process, and extract data from SC3. We have developed a simple data acquisition system, RTQUAKE, which fully integrates with SEISAN. Its main function is to read real‐time data from SeedLink servers, do triggering of events, and store data in the SEISAN database. Some optional automatic processing can also be done. RTQUAKE works with the …