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

Goal Starting date End date purpose

1-1 Preliminary observation

April 4,2013 April 15,2013- Identify the types of available data

through public entities websites

1-2 Extracting and Organizing Required Data for Evaluation

April 15,2013 June 15,2013

- 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 2011Zoom-in is Limited in some

areas with high density wellsLimited reported data

•Job date•Injected Volume•Lat, Lon, Depth•Chemical composition

of injectateAbout 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

10180 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

1.0 10.0 times about 32 times

0.5 3.2 times about 5.5 times

0.3 2.0 times about 3 times

0.1 1.3 times about 1.4 times

M < 2.0 Micro Microearthquakes, not felt, or felt rarely by sensitive people. Recorded by seismographs.

Continual/several million per year

2.0–2.9Minor

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

4.0–4.9 LightNoticeable 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

5.0–5.9 ModerateCan 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

32

101

Magnitude Average Annually

8 and higher 1

7 - 7.9 15

6 - 6.9 134

5 - 5.9 1319

4 - 4.9 ~13,000

3 - 3.9 ~130,000

2 - 2.9 ~1,300,000

Based on observations since 1900., USGS website

Worldwide Frequency of Occurrence of Earthquakes

Earthquake Facts

California SeismicityFrom 1980-2013 : 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

10180 events outside area; 179 greater than 3

939 events inside area; 33 greater than 3519 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

Goal Starting date End date purpose

2-1 Describing the distribution of seismicity in space, time and magnitude

June 15,2013 July 15,2013- Using Gutenberg Richter to delineate

difference between the induced seismicity and Earthquakes

2-2 probabilistic hazard forecast

June 15,2013 July 15,2013

- 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 EventsEvents 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 dataSchorlemmer et al. (2005) Zoback, 2007

b- value analysis  Number of Events b- valueAll Events 10180 0.98Out of major fault zone 939 1.02Shallow events out of major fault zone (1980-2013) 519 1.1Shallow events out of major fault zone (1990-2013) 271 1.34

b-value Analysis of induced seismicity

1990-2013 (23 years)

Mag >3 >4

Number 5 none

b=1.25

b=1

Not Probable

Correlating seismicity with field operation parameters

Goal 3: Correlating seismicity with field operation parameters

Goal Goal Goal Goal

3-1 Developing correlations between field operations parameters and resultant seismicity

July 15,2013 August 15,2013

- Using preexisting models for further study of correlations

- Drawing local examples using analyzed correlations

Initial Steps

Seismicity clustering for each field

Date Time MAG LAT LON DEPTH EVID NP11/18/2011 33:20.7 2.98 35.175 -119.391 0 15076884 51

Magnitude 1 2 3

Date Time MAG LAT LON DEPTH EVID NP9/5/2012 31:06.7 2.77 35.322 -119.487 0 15211169 41

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

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