The Priddis multicomponent seismograph station, local seismicity, and oilfield earthquakes
R. James Brown, Carl J. Gunhold, Malcolm B. Bertram, Eric V. Gallant
An earthquake seismograph station is in provisional operation near Priddis, Alberta, telemetering data from a short-period vertical-component seismometer to The University of Calgary. There the data are recorded and displayed on a visual drum recorder. Three broadband seismometers have recently been acquired and will be installed in an orthogonal three-component configuration to upgrade the station to the capability of a so-called standard Canadian seismograph station. This final installation phase will include the construction of a small subsurface vault to house the four seismometers, and the acquisition of a microcomputer system for data steering and storage.
There are several good reasons for an earthquake station in the Calgary area, where, at present, there is no other station within 200 km. The regional seismicity is not very high but Calgary has been shaken twice in the last 11 years by earthquakes in Idaho and southern Alberta. There is low-level seismicity associated with some nearby areas where there has been significant hydrocarbon production, for example, near Turner Valley and Rocky Mountain House. There is also low-to-moderate seismicity in parts of the Rocky Mountain Trench; and in the Blairmore-Fernie-Waterton region there are geologically well documented instabilities. In general, there is a need for a more complete catalogue of earthquake activity for the southern Alberta region that could be part of environmental-impact studies (including seismicity) associated with construction of sensitive installations such as dams, power plants, etc.