What is seismicity? 2

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2 What is seismicity? 2

3 How is Seismicity measured? Modified Mercalli Intensity (MMI) Effect Richter Scale (local magnitude) I II III IV V VI VII VIII IX X XI XII Not Felt by People Weak Light. Moderate Strong. Shaking. small objects move Very Strong. Felt by everyone. Light damage. Considerable damage Violent. Landslides. Few Structures Remain standing Total damage

4 Causes of Induced Seismicity? 4

5 Why Study Earthquakes Surface Effects and Ground Motion Public safety Property damage (buildings, roads, bridges, pipelines, water reservoirs) Wellbore integrity Reservoir seal / Aquifer containment Casing deformation Environmental impacts Flooding Tsunami Landslides Social License Regulatory directives Stakeholder perspective 5

6 How often do seismic events occur? 6

7 How often do seismic events occur? 7

8 USGS 2014 Seismic Hazard Model Including Natural Earthquakes 8

9 USGS 2016 Seismic Hazard Model Including Natural and Induced Earthquakes 9

10 US Mitigation Measures 1. Increased monitoring and reporting 2. Traffic Light System for disposal wells 3. Seismicity review for new wells 4. Mechanical Integrity Tests 5. Public reporting 10

11 Earthquakes in Canada 11

12 NRCAN 2015 Seismic Hazard 12

13 Alberta Earthquakes 88 years 9 years 13

14 Seismicity Mapping in the WCSB Canadian National Seismic Network (CNSN) Geoscience BC The Canadian Rockies and Alberta Network (CRANE) Regional Alberta Observatory for Earthquake Studies Network (RAVEN) Alberta Telemetered Seismic Network (ATSN) TransAlta Dam Network (TD) Montana Regional Seismic Network (MRSN) 14

15 Seismicity Mapping in the WCSB Major Bedrock Faults of Alberta

16 Seismicity Mapping in the WCSB

17 Seismicity in WCSB Fort St. John Cluster Extraction and disposal (since 2000) Snipe Lake 1970 Potentially enhanced recovery injection Crooked Lake (2015) Hydraulic Fracturing Brazeau River (since 1960) Disposal Injection Turner Valley (1970 s) Hydrocarbon extraction Rocky Mountain House (1970 s) Hydrocarbon extraction Baranova V. et. al Shultz et. al. 2014;

18 Northeast British Columbia 2012 Investigation of 231 seismic events: 38 induced by wastewater disposal (from 2 wells) 193 induced by hydraulic fracturing events (2.6% of wells) Mitigation Actions Increased seismic monitoring (new seismograph stations and dense array stations) Fault mapping and identification of stressed faults Data collection and evaluation of linkage between rate and pressure. Important for disposal Less important for hydraulic fracturing BC Oil and Gas Commission

19 Rocky Mountain House Seismic events and gas production AER OFR Stern et. al (2013) Eaton Babaie (2015) 19

20 Canadian Induced Seismicity Collaboration AGS, U of A, AER 20

21 What are we doing? High density arrays Increased monitoring Disposal well licenses require seismicity review Traffic light approach 21

22 Concerns and Mitigation Moving Forward 1. Impact on Social License Operator transparency builds trust in the community 2. Lack of understanding of where/why Update major fault mapping Mapping of geomechnical parameters 22

23 Concerns and Mitigation Moving Forward 3. Understand area specific tolerance or acceptable risk Hazard mapping that includes induced seismicity 4. Continued seismic monitoring Before-during-after Collaboration on dense array monitoring 5. Impact on Disposal Most likely to face regulatory reductions Schultz et. al

24 Thanks! Ian Grant, P.Geo., M.Sc. Senior Hydrogeologist Integrated Sustainability Consultants Ltd. 600, 540 5th Avenue SW, Calgary, Alberta T2P 0M2 24

25 Bibliography Adams, J., and Halchuk S Fourth generation seismic hazard maps of Canada: Values for over 650 Canadian localities intended for the 2005 National Building Code of Canada, Geol. Surv. Canad. OpenFile Rept. 4459, 150 pp. Alberta Energy Regulator Alberta's Earthquakes. Accessed Online at Alberta Energy Regulator Induced Seismicity. Accessed Online at Atkinson G.M., Eaton D.W., Ghofrani H., Walker D., Cheadle B, Schultz R., Shcherbakov R., Tiampo K, Gu J, Harrington R.M., Liu Y., van der Baan M., and Kao H Hydraulic Fracturing and Seismicity in the Western Canada Sedimentary Basin. Seismological Research Letters, Volume 87(3), May/June Atkinson, G., H. Ghofrani, and K. Assatourians Impact of induced seismicity on the evaluation of seismic hazard: Some preliminary considerations, Seismol. Res. Lett. 86, Baranova, V., A. Mustaqeem, and S. Bell A model for induced seismicity caused by hydrocarbon production in the Western Canada Sedimentary Basin. Canadian Journal of Earth Sciences 36: DOI: /cjes Boroumand N. and Maghsoudi S A Cheat Sheet on Induced Seismicity. CSEG (Canadian Society of Exploration Geophysicists.) Recorder April BC Oil and Gas Commission Investigation of Observed Seismicity in the Horn River Basin. Aug 2012 BC Oil and Gas Commission Investigation of Observed Seismicity in the Montney Trend., Dec 2014 Milne, W. G The Snipe Lake, Alberta earthquake of March 8, Canadian Journal of Earth Sciences, 7(6), doi: /e Petersen, M.D., Moschetti, M.P., Powers, P.M., Mueller, C.S., Haller, K.M., Frankel, A.D., Zeng, Yuehua, Rezaeian, Sanaz, Harmsen, S.C., Boyd, O.S., Field, Ned, Chen, Rui, Rukstales, K.S., Luco, Nico, Wheeler, R.L., Williams, R.A., and Olsen, A.H., Documentation for the 2014 update of the United States national seismic hazard maps: U.S. Geological Survey Open-File Report , 243 p., Petersen, M.D., Mueller, C.S., Moschetti, M.P., Hoover, S.M., Llenos, A.L., Ellsworth, W.L., Michael, A.J., Rubinstein, J.L., McGarr, A.F., and Rukstales, K.S., One-year seismic hazard forecast for the Central and Eastern United States from induced and natural earthquakes (ver. 1.1, June 2016): U.S. Geological Survey Open-File Report , 52 p., Schultz, R., V. Stern, and Y. J. Gu An investigation of seismicity clustered near the Cordel Field, west central Alberta, and its relation to a nearby disposal well, J. Geophys. Res. Solid Earth, 119, , doi: /2013jb Schultz, R., V. Stern, M. Novakovic, G. Atkinson, and Y. J. Gu Hydraulic fracturing and the Crooked Lake Sequences: Insights gleaned from regional seismic networks, Geophys. Res. Lett., 42, , doi: /2015gl Schultz R., Corlett H., Haug K., Kocon K., MacCormack K., Stern V., and Shipman T Linking fossil reefs with earthquakes: Geologic insight to where induced seismicity occurs in Alberta, Geophysical Research Letters 43, , doi: /2015gl Stern, V.H., Schultz, R.J., Shen, L., Gu, Y.J. and Eaton, D.W Alberta earthquake catalogue, version 1.0: September 2006 through December 2010; Alberta Energy Regulator, AER/AGS Open File Report , 29 p. Wetmiller, R. J Earthquakes near Rocky Mountain House, Alberta, and their relationship to gas production facilities. Canadian Journal of Earth Sciences, 23(2), doi: /e