The BC Energy Regulator has adopted the local magnitude determination methodology as the magnitude standard for northeast B.C. and for regulatory decisions.
DATE ISSUED: Feb. 10, 2021
EFFECTIVE DATE: Immediately
The BC Energy Regulator (Regulator) has adopted the local magnitude determination methodology outlined by Babaie Mahani and Kao, 2020 as the magnitude standard for northeast B.C. and for regulatory decisions.
The adoption of a local magnitude standard and the recent deployment of additional seismograph stations in northeast B.C., reflects the Regulator’s commitment to a continual focus on research and understanding of induced seismicity. Reliable magnitude information is crucial for monitoring and timely decisions with respect to induced seismicity.
This methodology replaces the Richter-based formula to better reflect the characteristics of northeast B.C.’s geology and meets a recommendation from the Scientific Hydraulic Fracturing Review Panel to develop a guideline for standardized magnitude calculation.
The updated local magnitude determination used a detailed earthquake dataset for the period 2014-2018 (inclusive). This dataset was used to revise the distance correction model and better characterize the attenuation effects in the local magnitude calculation of earthquakes in northeast B.C.
The update to local magnitude determination provides higher consistency between magnitude values calculated at individual stations and the final event magnitude over a wide hypocentral distance range from two to 600 km. An extended abstract on this subject has been published in the CSEG RECORDER.
If you have any questions regarding this Industry Bulletin, please contact:
Stuart Venables, P.Geo
Sr. Petroleum Geologist, Operations Division
BC Energy Regulator
stuart.venables@bcogc.ca
250-419-4472
References
Babaie Mahani, A. and H. Kao (2020). Determination of Local Magnitude for Induced Earthquakes in the Western Canada Sedimentary Basin: An Update, RECORDER, V. 45, No. 02, 12 pages, https://csegrecorder.com/articles/view/determination-of-local-magnitude-for-induced-earthquakes-in-the-wcsb