| Title | Performance evaluation of the regional seismograph network in northeast British Columbia, Canada, for monitoring of induced seismicity |
| |
| Author | Mahani, A B; Kao, H ; Walker, D; Johnson, J; Salas, C |
| Source | Seismological Research Letters vol. 87, no. 3, 2016 p. 648-660, https://doi.org/10.1785/0220150241 |
| Image |  |
| Year | 2016 |
| Alt Series | Earth Sciences Sector, Contribution Series 20150350 |
| Publisher | Seismological Society of America (SSA) |
| Document | serial |
| Lang. | English |
| Media | paper; on-line; digital |
| File format | pdf |
| Province | British Columbia |
| NTS | 93N/01; 93N/02; 93N/07; 93N/08; 93N/09; 93N/10; 93N/15; 93N/16; 93O; 93P; 94A; 94B; 94C/01; 94C/02; 94C/07; 94C/08; 94C/09; 94C/10; 94C/15; 94C/16; 94F/01; 94F/02; 94F/07; 94F/08; 94F/09; 94F/10; 94F/15;
94F/16; 94G; 94H; 94I; 94J; 94K/01; 94K/02; 94K/07; 94K/08; 94K/09; 94K/10; 94K/15; 94K/16; 94N/01; 94N/02; 94N/07; 94N/08; 94N/09; 94N/10; 94N/15; 94N/16; 94O; 94P |
| Lat/Long WENS | -125.0000 -120.0000 60.0000 55.0000 |
| Subjects | environmental geology; geophysics; miscellaneous; environmental geology; hydraulic fracturing; seismic arrays; seismic interpretations; seismic risk; seismic surveys; seismic data; seismic methods;
earthquakes; earthquake studies; Impacts of Hydraulic Fracturing |
| Illustrations | bar graphs; linegraphs; seismic maps; location maps; equations |
| Program | Environmental
Geoscience Shale Gas - seismicity |
| Released | 2016 03 02 |
| Abstract | An important factor in mitigation of seismic hazard from induced seismicity is properly established seismic networks suitable for consistent identification of small-to-moderate events (magnitudes less
than four). Here, we evaluate the performance of the newly established regional broadband seismic network in northeast British Columbia, Canada. The seismic network was designed for monitoring of induced seismicity due to oil and gas operations
related to hydraulic fracturing and fluid injection in the region. We use regional and local earthquake catalogs for the period 1985-2015 to analyze magnitude of completeness and epicentral uncertainty. We also perform a theoretical assessment of
minimum detectable magnitude across the study region based on analysis of ambient noise and simulated ground motions. From the frequency-magnitude distribution of the reported events in the regional earthquake catalog, the magnitude of completeness
has decreased ?1 magnitude unit from ?3 in the periods 1985-2013 to ?2 in the period 2013-2015 as a result of the establishment of new stations. The minimum detectable magnitude in the region is 1.6-2.6 based on the signal-to-noise ratio (SNR) of 10
and higher at four or more stations. By comparing the regional and dense array catalogs, we determine that the error in epicentral location in well-constrained areas by seismic stations is below 3 km in both east-west and north-south directions.
However, location uncertainties can be up to 10 km in the east-west direction in areas where the current regional network is sparse. The magnitude detection threshold in the Montney Play, where most of the current oil and gas activities are taking
place, can be further reduced by up to 1 magnitude unit with the addition of four new stations. |
| Summary | (Plain Language Summary, not published)
New seismograph stations have been established in northeast British Columbia since 2013 to study possible induced seismicity related to local oil and gas
operations. Based on the quantitative analysis presented in this paper, we report that the increase station density has lowered the detection threshold of local earthquakes in the northeast BC region by one magnitude unit from ~3 in the period of
1985-2013 to ~2 after 2013. The location error is estimated to be less than 3 km in both north-south and east-west directions. |
| GEOSCAN ID | 297430 |
|
|