shale gas...impact on water resources from water used in hydraulic fracturing inadequate transport...

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Shale Gas What is it, do we need it, how do we get it and

what are the implications?

Professor Peter Styles,

President International Commission on Hydrocarbon Related Seismicity

Applied and Environmental Geophysics Research Group

SDNPA Meeting 15 October 2013

Coal Fired Power Stations United Kingdom

Kingsnorth will close by 2015 Grain will close by 2015

Ironbridge will close by 2015 Didcot will close by 2013 Fawley will close by 2013

Cockenzie will close by 2013

World World Resources Institute

identifies 1,200 coal plants in planning across 59 countries, with about three-quarters in

China and India

Source: The Guardian, Tuesday 20 November 2012

BP: World Energy Outlook

Gas isn’t on this cartoon yet!

Technophobia

Where do hydrocarbons Live?

FRACK – A Geologist’s View of Hydraulic Fracturing

Sand Grain

Oil or Gas

Water Film

~1mm

Where Gas Lives

Conventional? Unconventional?

Yes you CAN tell the difference!

Unconventional? Conventional?

NO you CAN’T tell the difference!

Bowland Shale, organic-rich and thick

• S

Formby natural oil seepage

The estimate is in the form of a range to reflect geological uncertainty. The lower limit of the range is 822 tcf and the upper limit is 2281 tcf, but the best estimate for the resource is 1329 tcf.

BGS Estimates of Resource available from Shale Gas in Northern England

Approximately 25 to 50 years of UK Gas

Consumption even at an extraction ratio of 10%!

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Hydrofracturing in the UK

• Not new!! >200 fracs – Carried out for water,

– Carried out for Geothermal Energy

– Carried out for Coal Bed Methane

– Microseismicity Monitored as long ago as 1988

Beckingham, Lincolnshire

Hydrofrac Monitored by

my (PS) Research Group

(while at Liverpool) in

1988/1989 with BP!!

UK Fracking to Date >200 of various types

Cheshire 1992

West Sussex 1991

Conventional petroleum environmental Potential impacts

• Visual intrusion

• Noise

• Increased traffic

• Air pollution

• Water contamination

• Soil contamination

• Green-house gas emissions

So what makes shale gas different? Nothing Really!

Potential for:

1. Visual intrusion, noise, traffic & dust

2. Gas, fracc-fluids and formation waters escaping to surface?

3. Well casing failure due to the high fracking pressures?

4. Gas contamination of aquifers and near surface soils?.

5. Surface spills of fuel, chemicals or flow-back waters?

6. Release of greenhouse gases to atmosphere?

7. Low-magnitude earthquakes/

Clean water

Possible

Aquifer

Confining

Layers

Water table

To river

or STW

Gas

emissions to

atmosphere Production

Platform Storage

tanks

Production

Zone

Environmental risks of shale gas extraction

Contamination of groundwater due to

mobilization of solutes or methane

Contamination of groundwater due to poor well design or

failure

Fugitive emissions of

methane

Contamination of soil, surface or

groundwater due to spills of chemicals or

return fluids

Inadequate transport or treatment of waste waters

Impact on water resources from water

used in hydraulic fracturing

Inadequate transport or

processing of produced gas

Inadequate treatment/disposal of

drill cuttings

Environmental controls (England and Wales)

Risk Controls

Groundwater pollution

Water Framework Directive and Groundwater Daughter Directive through the Water Resources Act and Environmental Permitting Regulations (EPR): Regulate discharges to groundwater, require disclosure of chemicals.

Surface spills Planning regime for site construction standards. EPR regulates discharges to surface water and groundwater.

Disposal of used fracking fluid

Mining Waste Directive through EPR: Waste management plan must be approved by the Environment Agency. Euratom Treaty if naturally occurring radioactive materials, via EPR.

Over abstraction of water

Abstraction licensing under the Water Resources Act.

Fugitive methane emissions

Borehole regulations (HSE) to protect human health. Conditions under Petroleum Licences (DECC) for flaring and venting. Mining Waste Directive may apply.

3D micro-seismic mapping in real time

(National Energy Board, Canada)

Maximum upward growth 588 m (Barnett Shale

Maxwell (2012)

The Key To Fracking Is A Good Cement Job

Uncemented casing is the main factor in surface casing vent flow, gas migration and/or casing failure Good quality cementing will protect wells against cement degradation and casing corrosion

Well construction Pressure testing and ‘Cement Bond Log’ (CBL)

Conductor Surface

Intermediate

Production

Long Term Well Integrity

• “It is interesting to note that The Pantheon in Rome, Italy was built about 126 AD. Besides its age, the unusual aspect of this structure is its concrete dome. “Almost two thousand years after it was built, the Pantheon’s dome is still the world’s largest unreinforced concrete dome. The height to the oculus and the diameter of the interior circle are the same, 43.3 meters (142 ft).” As important, is the fact that this dome has few cracks”

• Barry Stevens

Water Usage: CONTEXT

• About 2.5 Million Gallons of water / well

Shale Gas & Aquifers Treehugger.com

Enormous Gas Leak?

CSIRO &McKay Reports

Surface spills

• Can be avoided by fully lined and bunded pads

CBM at Keele

• Production pilot planned on site end 2009

• Will test productive capacity of coals

• Ultimately looking to supply gas to the University

Great Row

Etruria Fm

Newcastle Fm

Science Park

65 o

Tru

e D

ip

62 o

Appare

nt D

ip

427’

-244’ TVDSS

GL=559’

15o True Dip

5o Apparent Dip

Fau

lt “A”

Newcastle Fm

Etruria Fm

+400’ TVDSS

-610’ TVDSS

Burnwood

Cannel Row

Rowhurst

Winghay

RagmanFive FeetMoss

Bay MB

Ten Feet

Red ShagRed Mine

Spencroft

Bassey

Great Row

1000’ Lateral

Blackband

-1000’

-2000’

MSL

-3000’

Upper Coal Measures

Middle Coal Measures

No vertical exaggeration

0 500 1000Feet

P&A open hole

Cased & cmtd hole

6” lateral (slotted liner)

Coal seam

Marine Band

Jet pump in

inclined Mother-

bore

Weak O/H sectionGreat Row

Etruria Fm

Newcastle Fm

Science Park

65 o

Tru

e D

ip

62 o

Appare

nt D

ip

427’

-244’ TVDSS

GL=559’

15o True Dip

5o Apparent Dip

Fau

lt “A”

Newcastle Fm

Etruria Fm

+400’ TVDSS

-610’ TVDSS

Burnwood

Cannel Row

Rowhurst

Winghay

RagmanFive FeetMoss

Bay MB

Ten Feet

Red ShagRed Mine

Spencroft

Bassey

Great Row

1000’ Lateral

Blackband

-1000’

-2000’

MSL

-3000’

Upper Coal Measures

Middle Coal Measures

No vertical exaggeration

0 500 1000Feet

0 500 1000Feet

P&A open hole

Cased & cmtd hole

6” lateral (slotted liner)

Coal seam

Marine Band

P&A open hole

Cased & cmtd hole

6” lateral (slotted liner)

Coal seam

Marine Band

Jet pump in

inclined Mother-

bore

Weak O/H section

Exploration phase is temporary

Before

During

After

(ExplorationPhase)

Courtesy IGas, Willoughbridge

O

• S

Dorset coast

• Corfe Castle

• World Heritage Site

• Heritage Coast

• Site of Special Scientific Interest (SSSI)

• Two Nature Reserves

• Poole and Bournmouth (pop 400k)

Spot the Eleven Wells?

Multiple wells drilled from one pad

Courtesy Statoil

Cuadrilla Preese Hall 1 Borehole

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Hydrofracturing Stages and Associated Seismicity at Preese Hall

Blackpool Earthquakes

Overview of injection volume and seismicity during treatment stages. Earthquake activity closely correlates with stages 2 and 4. The largest event with 2.3 ML at 02:34 on 1/4/2011 occurred shortly after stage 2.

• Earthquake activity was caused by fluid injection into a fault zone

• The fault failed repeatedly in a series of small earthquakes.

• The fault has now been identified.

• The injected volume and flow-back timing were important controlling factors

Epicentre of the Blackpool earthquakes (yellow star) in relation to the Preese Hall well. Depth is approximately 2250 m, which places the events close to the point of injection.

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Maximum Magnitude of Induced Events

• They happen in weaker, younger rocks, generally in sandstones of Carboniferous age, associated with coal mining

• Hydrofracture related events occur in even weaker rocks which are shales of Carboniferous age and so

• Are not likely to exceed the magnitudes which we have seen of about 3 which:

may be felt,

may in rare circumstances cause superficial damage (plaster)

but not structural damage

Where Shale Gas Induced Events sit on an Energy Scale

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Most Induced Events from Mining and Shale Gas

1.5 2.0 2.5

Seismicity: thousands of fracking operations in USA

x 30,000

x 1,000

Barnett Shale USA

Not felt felt

Lancashire, UK (2011) - exceptional

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Our (Green, Styles, Baptie DECC Report 2012) Proposals for any future HF operations elsewhere in

the UK (and elsewhere?)

We recommend a detailed analysis of potential seismic

hazards prior to spudding the well. This should include:

o Appropriate baseline seismic monitoring to establish background

seismicity in the area of interest.

o Characterisation of any possible active faults in the region using all available geological and geophysical data (BC always has 3-D seismic)

o Application of suitable ground motion prediction models to assess the potential impact of any induced earthquakes

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Our (Green, Styles, Baptie DECC Report 2012) Recommendations for Mitigation of Hazards

• The number of fluid injection induced earthquakes above a given magnitude will increase approximately proportionally to the injected fluid volume,

• Therefore reducing volumes and implementing flow back should reduce the probability of significant earthquakes.

• We therefore recommend that future fracture treatments

should initially be modified to reduce the probability of future induced earthquakes, by:

– reducing the injected fluid volume – initiating immediate flow back post-frac.

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Proposed Traffic Light System with Thresholds

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We concluded

• The risk of significant seismic activity associated with Hydraulic Stimulation in the UK is small and damage is extremely unlikely.

• Hydrofraccing should continue under a regime of careful microseismic and geomechanical monitoring

Can SHALE Gas Be Green(ER)?

FRACK – A Geologist’s View of Hydraulic Fracturing

The Economics of GAS

O Terms of reference

• Requested by Sir John Beddington FRS, Government Chief Scientific Adviser

• Independent review of scientific and engineering evidence

• What are major risks associated with hydraulic fracturing to extract shale gas?

UK Royal Society Conclusions

• The key findings of this review were:

• The health, safety and environmental risks can be managed effectively in the UK. Operational best practices must be implemented and enforced through strong regulation.

• Fracture propagation is an unlikely cause of contamination. The risk of fractures propagating to reach overlying aquifers is very low provided that shale gas extraction takes place at depths of many hundreds of metres or several kilometres. Even if fractures reached overlying aquifers, the necessary pressure conditions for contaminants to flow are very unlikely to be met given the UK’s shale gas hydrogeological environments.

• Well integrity is the highest priority. More likely causes of possible contamination include faulty wells. The UK’s unique well examination scheme was set up so that independent, specialist experts could review the design of every offshore well. This scheme must be made fit for purpose for onshore activities.

Technically possible

Economically Deliverable

Societally Acceptable

The Triangle of Truth for Shale Gas

The Only Energy Source We Want to Live Next To …

Public Understanding of Science