The past, present, future and applications of Canada’s analog seismic data

Canada has been seismologically instrumented for more than one hundred twenty-five years. Analog instruments were first deployed in Canada in 1897 and dominated seismic monitoring for almost a century until they were replaced by digital instruments, first deployed in the late 1970s in Canada. Although many analog seismograms have been lost, approximately one million remain. These records contain a wealth of data about earthquakes, explosions and many other phenomena. The analog seismogram collection is currently stored in a secure location and has legal protection. However, access is difficult and a path to scanning and digitizing the records remains elusive. Scanning and digitizing are necessary for modern analysis techniques to be used to unlock their secrets. Some of Canada’s largest, historical earthquakes have been analyzed using techniques of the 1980s and 1990s but science has progressed considerably in recent decades and all events would benefit from the application of newer analysis methods. There has been more success in converting textual records, such as station bulletins, to accessible, digital formats. This paper discusses the history of Canada’s legacy seismic data as well as challenges, successes and thoughts on moving forward.