00000nam 2200000za 4500 9.819694 CaOODSP 20251031142446 cr ||||||||||| 160620s2014 onc|||||o f|0| 0 eng d CaOODSP eng n-cn--- M183-2/7632E-PDF 2012 Haida Gwaii Mw 7.7 earthquake response - ocean bottom seismometer relocation and geophone orientation analysis and quality control of wide-angle P-wave refraction data [electronic resource] / [by] M. Riedel ... [et al.]. Ottawa : Natural Resources Canada, 2014. 77 p. : figures, graphs, tables. Open file (Geological Survey of Canada) ; 7632 Includes bibliographical references. Canada's second largest instrumentally recorded earthquake occurred on October 27th, 2012, off the west coast of Haida Gwaii. Analysis of seismic waveform data indicates that it was a thrust earthquake with a magnitude of 7.7. A set of 14 ocean bottom seismometers (OBS) were deployed for the duration of 1 month between December 2012 and January 2013 to record a portion of the aftershock sequence. An active source (airgun) seismic program was conducted in January 2013 using six OBS to aid in the earthquake location analyses. Using the airgun source data, each OBS position was first re-located. The OBS instruments drifted on average 200m to the NW of the ship¿s deployment position. The OBS geophone orientation was also determined using the airgun data. Long-range refraction seismic arrivals from the active-source experiment were identified on six Haida Gwaii land-stations with offset ranges of up to 70 km to be used in a crustal tomographic study. gccst Earthquakes gccst Seismology gccst Geophysics Riedel, Michael. Canada. Natural Resources Canada. Geological Survey of Canada. Open file (Geological Survey of Canada) 7632 (CaOODSP)9.506878 PDF 2.77 MB https://publications.gc.ca/collections/collection_2016/rncan-nrcan/M183-2-7632-eng.pdf