This layer is part of the Geological Survey of Canada's earthquake monitoring network. There are some blank fields toward the beginning of the listing, from the time the network was being installed and hence parameters were often unknown. Also, all depths in the table are "fixed" to a depth which is an integer multiple of 5km, according to lowest obtainable residuals and known crustal structure. The number and magnitude of located events are also dependent on the time recorded, as the magnitude threshold lowered as more stations were installed. The larger, potentially damaging earthquakes, however, were likely recorded from the inception of the network as these events produce waves which reach the entire western network.
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