California Project Seismicity in the oil and gas fields Tayeb A. Tafti University of Southern California July 2, 2013

 Research Team Structure  Problem Statement  Extracting Data from public entities websites  Preliminary observation  Seismicity Statistics and Prediction Studies  Correlating seismicity with field operation parameters Outline

 Find seismicity that related to oil field operations?  What will be future forecast for seismicity in the area?  What are the field operation parameters that correlates with seismicity? Problems…

Goal 1: Extracting Data from public entities websites GoalStarting dateEnd datepurpose 1-1 Preliminary observation April 4,2013April 15, Identify the types of available data through public entities websites 1-2 Extracting and Organizing Required Data for Evaluation April 15,2013June 15, Generating catalogue for each field and each basin - Generating information Queries for Wells near observed seismicity Extracting Data from public entities websites

Preliminary observation  Faults map from USGS

Preliminary observation  Hydraulic fracturing jobs from fracfocus  Data only from January 2011  Zoom-in is Limited in some areas with high density wells  Limited reported data Job date Injected Volume Lat, Lon, Depth Chemical composition of injectate  About 923 reported jobs in this area after Jan 2011, Pdf files should be extracted for each and digitally stored  Out of them 533 information for wells digitally stored in USC database

Preliminary observation  Seismic Stations

Preliminary observation  Seismicity in the area  recorded events in this area from 1980 to June 2013  3 Events more than 5; 1988,1993,2005: Largest 5.7

Earthquake Facts Magnitude Change Ground Motion Change (Displacement) Energy Change timesabout 32 times timesabout 5.5 times timesabout 3 times timesabout 1.4 times M < 2.0Micro Microearthquakes, not felt, or felt rarely by sensitive people. Recorded by seismographs. Continual/several million per year 2.0–2.9 Minor Felt slightly by some people. No damage to buildings.Over one million per year 3.0–3.9 Often felt by people, but very rarely causes damage. Shaking of indoor objects can be noticeable. Over 100,000 per year 4.0–4.9Light Noticeable shaking of indoor objects and rattling noises. Felt by most people in the affected area. Slightly felt outside. Generally causes none to minimal damage. Moderate to significant damage very unlikely. 10,000 to 15,000 per year 5.0–5.9Moderate Can cause damage of varying severity to poorly constructed buildings. At most, none to slight damage to all other buildings. Felt by everyone. Casualties range from none to a few. 1,000 to 1,500 per year

Magnitude Average Annually 8 and higher ~13, ~130, ~1,300,000 Based on observations since 1900., USGS website Worldwide Frequency of Occurrence of Earthquakes Earthquake Facts California Seismicity From : Number of Earthquakes

Preliminary observation  Seismicity in the area  939 recorded events in this area from 1980 to June 2013  3 Events more than 4:  1980(24.4 km);1985(9.9);1988(unknown depth in catalogue, relocated in USC); Two of them relates to Faults network in Elk Reserves.

Preliminary observation Events less than 6.0 km events outside area; 179 greater than events inside area; 33 greater than events;15 events greater than 3 No events with Magnitude 4 or above All Events

Seismicity Statistics and Prediction Studies Goal 2: Seismicity Statistics and Prediction Studies GoalStarting dateEnd datepurpose 2-1 Describing the distribution of seismicity in space, time and magnitude June 15,2013July 15, Using Gutenberg Richter to delineate difference between the induced seismicity and Earthquakes 2-2 probabilistic hazard forecast June 15,2013July 15, Providing the annual probability and recurrence time of seismicity with different magnitude related to oil field operations. The preliminary historic catalogs will be compiled for this study.

Preliminary observation All Events Events less than 6.0 km & Outside of fault zone

b-value Analysis current state of art Many authors reported b = 1 as a universal constant for earthquakes in general (Frohlich, 1993; Kagan, 1999) Higher b-values may occur in lower stress regimes with smaller magnitude (Zoback, 2007, Goebel 2012, Spada 2013, Tafti 2013) Gutenberg and Richter, 1944 Southern California field data Schorlemmer et al. (2005) Zoback, 2007

b- value analysis Number of Eventsb- value All Events Out of major fault zone Shallow events out of major fault zone ( ) Shallow events out of major fault zone ( )

b-value Analysis of induced seismicity (23 years) Mag>3>4 Number5none b=1.25 b=1 Not Probable

Correlating seismicity with field operation parameters Goal 3: Correlating seismicity with field operation parameters Goal 3-1 Developing correlations between field operations parameters and resultant seismicity July 15,2013August 15, Using preexisting models for further study of correlations - Drawing local examples using analyzed correlations

Initial Steps

Seismicity clustering for each field DateTimeMAGLATLONDEPTHEVIDNP 11/18/201133: Magnitude 1 2 3

DateTimeMAGLATLONDEPTHEVIDNP 9/5/201231: Seismicity clustering for each field Magnitude 1 2 3

Seismicity clustering for each field No events after 2011, except one in 1992 all occurred in 1988

Seismicity clustering for each field No reported events after 2011 from Hydraulic Fracturing Magnitude 1 2 3

Seismicity clustering for each field No reported events after 2011 from Hydraulic Fracturing, seismicity may related to Hydraulic fracturing Magnitude 1 2 3

Seismicity clustering for each field No reported events after 2011 from Hydraulic Fracturing Magnitude 1 2 3

Seismicity clustering for each field No reported events after 2011 from Hydraulic Fracturing, all occurred in 1988 Magnitude 1 2 3

Seismicity clustering for each field No reported events after 2011 from Hydraulic Fracturing, occurred in 1988 Magnitude 1 2 3

Seismicity clustering for each field No events from any field activity such as cyclic steam, water inj., or Hydraulic fracturing

Thank you