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étiquettes: physical sciences, geology, earthquake, seismology, Canadian Shield

Objectif(s): To provide information on crustal and mantle structures to determine whether Banks Island forms a rifted margin, or forms the northern extension of the Canadian Shield.

Description du projet: This project is aimed at understanding the structure and evolution of the crust and mantle beneath Banks Island in the western Arctic by analyzing new seismic data collected from an array of broadband seismic stations. The objective is to provide information on crustal and mantle structures to determine whether Banks Island forms a rifted margin, or forms the northern extension of the Canadian Shield. This project requires the installation of a small network of seismograph stations across Banks Island that record distant earthquakes. Each station consists of a sensor buried <1 m in gravel, a data recorder or satellite dish, solar panels and battery/electronics boxes. Each site is autonomous and no chemical product is used around the site. Seismic waves travel from distant earthquakes occurring around the globe to be recorded by the sensor. The data are then either transmitted in near-real time via satellite telemetry or downloaded onto a disk taken to Ottawa where they can be processed, analyzed, archived and made publicly accessible via the Internet. Currently, two seismic stations are located at Sachs Harbour and Paulatuk. These stations were installed in August of 2013 as part of the Transportable Array of USArray. One additional seismic station was installed at Johnson Point on Banks Island on 13 August 2014. In this project we propose to deploy an array of 4 seismograph stations along an approximate west-to-east corridor that complements the existing stations and forms a small array. The seismic equipment first needs to be shipped to Inuvik for pre-assembly. The stations would remain operational for the duration of the project (2 years). The W-E shape of the linear array forms an ideal geometry to test the hypotheses outlined above. The project results will be presented at the Geoscience Forum in Yellowknife. The results will be communicated to the communities and band councils in plain language summaries. The fieldwork for this study will be conducted from July 22, 2015 to July 26, 2015.