Monitoring seismic activity in Canada’s North
Canada’s southwestern Arctic is of special interest to scientists exploring the interrelated roles of seismic activity, climate change and coastal erosion. Natural Resources research scientist Andrew Schaeffer recently travelled to the Northwest Territories to perform maintenance on four seismic stations and install a new one; click on any image to view a larger size. For more details about Andrew’s work, see this
Simply Science story.
Click on an image to view a larger size.
Sachs Harbour Airport, Banks Island. Andrew is en route from Inuvik to Bar Harbour at the northwest corner of Banks Island, Canada’s fifth-largest island, a trip of 900 kilometres. The pilot has to refuel the Aklak Air Twin Otter before continuing to the seismometer site, another 260 km away.
Along the way, they stop to swap batteries. Site locations are selected in part by how easy it is to land and take off. Most stations are close to the coast, with the farthest standing 20 km away. The Nelson Head location is 500 metres from the coast at an elevation of 100 metres.
The hills of southern Banks Island appear in the distance. Part of doing maintenance involves checking data from the stations and then integrating it into existing seismic information. For a typical analysis, accurate modelling requires a minimum of two years of information, though more is better.
It’s right on the beach, but Johnson Point is like the edge of the world. This maintenance visit included replacing a solar panel that had been broken before by wildlife, likely wolves or a polar bear.
Andrew and Clement install a new instrument in Tuktoyaktuk a few weeks before Tuktoyaktuk Science Day on August 1.
They had to dig down a metre and install an outer black pipe, which stands around the inner pipe that holds the instrument; they then fill the gaps with sand. This site is co-located with the Canadian Hydrographic Service Tide Gauge station and therefore runs on AC power. Next year, an internet connection will let it stream data in real time.
The repaired seismic station at Johnson Point. This probably won’t be Andrew’s last stop in Canada’s Arctic, return trips will be made to download data, replace batteries and conduct repairs as needed.
Flying north, up the west coast of Banks Island, between Sachs Harbour and Bar Harbour. Andrew finds more surface water run-off in early July than he’s seen in the past five years: what are usually small isolated creeks are now swollen rivers. Ice on the Beaufort Sea can be seen in the distance.
Northwest corner of Banks Island, Bar Harbour Andrew Schaeffer and University of Ottawa Ph.D. student Clement Esteve perform maintenance on a seismometer. A visit usually includes replacing batteries and downloading data. This job took about three hours because some of the snow was waist-high – in July! It’s the first time Andrew has seen snow at this location in five years.
Since the seismometer is positioned about a metre below the surface, someone has to dive in head first to level the unit!
Victoria Island, a short distance north of the Hamlet of Ulukhaktok, where another seismometer is installed.
Johnson Point site flowers.
Purple saxifrage (Saxifraga oppositifolia), Nunavut’s official flower, one of the few pops of bright of colour in the Arctic spring.