an introduction to fibre-optic distributed acoustic sensing...

© Copyright OptaSense Ltd. 2013

An introduction to fibre-optic

Distributed Acoustic Sensing and

its impact on IOR and EOR

Finding Petroleum: New technologies for

describing and monitoring reservoirs

David Hill, CTO

26 November 2013

© Copyright OptaSense Ltd. 2013 2

A quick Summary Our services

1. Hydraulic Fracture Profiling:

Measurement of fluid / proppant placement

2. Permanent Wellbore Monitoring:

Visualising flow dynamics & obtaining PLT readings without well intervention.

3. Seismic Recording: On demand full well bore imaging without intervention.


Who we are


OptaSense®

• OptaSense™ is part of the QinetiQ Group, a UK based multinational R&D organisation employing 9,000 people worldwide, with revenues of around $2.5 billion per year.

Oil Field Services

OFS Operations Centre, Calgary

• OptaSense™ has 165 staff and is headquartered in the UK with offices in USA, Canada, UAE and Australia.


OptaSense® Oil Field Services Applications

Oil Field Services

Completions

Cement cure monitoring

Hydraulic Fracture

Profiling (HFP)

Cross Well Communication

Microseismic

Production

Steam flow profiling

Casing leak detection

Production Logging

Evaluation

Land based Vertical Seismic Profiling (VSP)

Offshore Vertical Seismic Profiling (VSP)


OptaSense® Oil Field Services Applications

Oil Field Services

Completions

Cement cure monitoring

Hydraulic Fracture

Profiling (HFP)

Cross Well Communication

Microseismic

Production

Steam flow profiling


Production Logging

Evaluation

Land based Vertical Seismic Profiling (VSP)

Offshore Vertical Seismic Profiling (VSP)


Completions


Hydraulic Fracture Profiling Real-time DAS-HFP™ display

Pump

rates

Long

period

DAS

Short

period

DAS

DTS

Uptake

calc


Hydraulic Fracture Profiling Using OptaSense DAS-HFP™ to monitor an effective fracture treatment


Hydraulic Fracture Profiling Real-time estimation of proppant and fluid placements

Proppant Placement Fluid Placement

Stage 3

Perf 1 5 7

Perf 2 68 61

Perf 3 5 7

Perf 4 22 25

0

10

20

30

40

50

60

70

80

DA

S C

aclc

ula

ted

% D

istr

ibu

tio

n


Microseismic event detection For passive and frac generated events

Well head

Channel 300

Channel

400

• Detection of low frequency, high magnitude (>-1.5) microseismic events initiated at reactivated faults.

• Geolocation using 1 component (1C) sensor possible using shaped array localization

Time (ms)

Vert

ical

part

of w

ell

Heal of

well

Horizonta

l

part

of w

ell

P-wave:

5.37e+03 m/s

S-wave:

3.29e+03 m/s

Another

smaller micro-

seismic event


Production


Flow assurance

• Permanent Production Logging:

– Gas & Liquid rates per Well / Zone / Perf, and 2-phase flow

Cost reduction and increased understanding

In-flow

In-flow

In-flow

DAS optical

sensing cable

Bend

Well Head

GLM 1

GLM 2

Packer

ICV D

ICV C

ICV B

V ≈ 1 m/s

Slug flow in a vertical well section

• Flow assurance near term targets:

– Qualitative detection of fluid entry at perforations.

– Quantitative inflow profiling over perforations.

– Quantitative axial-flow profiling over stages.

– Quantitative (slug) velocity profiling over stages.


Flow assurance Examples of DAS data taken on unconventional gas producers

Courtesy of Shell


Qualitative flow monitoring Horizontal well with fibre behind casing

3D visualisation

of flow

2D waterfall

of flow

Dep

th

Time

Replay speed x1,120


Courtesy of Shell

Flow Assurance

• Production profiles estimated from DAS-PLT™ for three sequential production periods in an unconventional gas producer.

The next step: Quantitative inflow profiling – DAS-PLT™


Well control

• No flow over ICV D when high pressure zone A is open

Smart oil producer

MID FREQUENCY BAND

Courtesy of Shell


Evaluation


OptaSense experience

• OptaSense is the industry leader in providing DAS-VSP™

– Experience conducting VSP in completed, horizontal, fishhook and slim-hole wells

– Over 80,000 shots of data acquired in field operations

– Typically hundreds of levels acquired with every shot

Providing VSP using DAS

2013 winner of the Hart’s E&P Meritorious Award for

Engineering Innovation (Geoscience)


DAS-VSP™

• Non-intrusive

– VSP in wells inaccessible to geophones

• Permanent

– Lower cost on-demand monitoring

• Full vertical coverage

– Better imaging

– Faster acquisition

• Retrofitable

– Deployable on tubing

– Synergies with in-well monitoring

• Robust

– Operable in HTHP wells

Providing unique advantages

Examples of OptaSense DAS-VSP™ seismic gathers


Reservoir monitoring

• EOR Surveillance Project

– Well and Reservoir Management to increase Ultimate Recovery by 5%

– Areal surveillance to track steam conformance

– Piloted monitoring methods over 1P area

Steam Injection for thermal Enhanced Oil Recovery (EOR)

• Key Challenges

– Very busy brown field

– Unstable steam injection

– Various sources of industrial noise

17P Development Steam in 2013

1P steam injection since Q1 2009

2nd footprint

1st footprint

1P 125m

1 k

m

10-acre inverted 7-spot patterns

• Key Uncertainties

– Vertical and horizontal sweep

– Steam injection preferential path

– Growth rate of the steam chest


Reservoir monitoring Data & Imaging – DAS on tubing vs. Geophones clamped to casing

Geophone

DAS

DAS image Geophone image

Natih EC

Reservoir

VSP well

2 vibes, 4 sweeps 1 vibe, 3 sweeps

• Field trial in 2012 DAS/DTS (on tubing) & geophones in the same well

• Data DAS noisier than geophones / lower SNR / tubing ringing

• Images Comparable / DAS slightly lower frequency, narrower

• Acquisition time Would be comparable if using two vibes for DAS

Walk-away VSP Raw data


• To monitor steam chest and heat development within the 17P pattern area

• To advise on future pattern spacing / design and infill strategy

1P steam injection

since Dec 2008

2nd footprint:

7P

1st footprint:

10P

1P 250m

1 k

m

10-acre inverted 7-spot patterns

Flower

Pattern

17P steam in Sept 2013

Reservoir monitoring Areal Surveillance Objectives


seismic coverage

by 1 DAS well

Reservoir monitoring

• December 2013 – Install DAS & DTS fibre-

optic cable in eight wells

• January 2014 – Acquire baseline 3D

DAS-VSP™ using virbroseis

• 2015, 2016, 2017 – Repeat survey

First ever multi-well 3D DAS-VSP™, simultaneous recorded worldwide

AL-188

AL-11

AL-105

AL-140

AL-191 AL-126

Observation

Injection

Production

Existing DAS Baseline DAS coverage outline

AL-128

AL-185


Dual well 3D VSP in deepwater

• FO cable deployed on the production string

• No rig time required

– Drastically savings

– Repeat at any time

Made possible by DAS-VSP™

• Two wells acquired simultaneously

• 50,000 shots in seven weeks

• ~1,400 DAS levels using pre-existing FO cable

• 70,000,000 traces

Courtesy of Shell


Dual well 3D DAS-VSP™ in Deepwater Utilising DAS-VSP™ data

• Excellent data quality

• Velocity calibration for positioning of new well

• Time-lapse imaging for water-injection monitoring


Summary


DAS provides unique sensing opportunities Multiple application applied over the life of the well

Time

Construction Completion Production

Flow back

Repeat VSP

Repeat VSP

Abandonment

Cement Job Assessment

Frac Monitoring

Flow

Subsidence monitoring

Baseline VSP

Microseismic Monitoring

Valve / Pump Monitoring

MMV VSP

Vertical Seismic Profile

Hydraulic Fracture Profiling

Hydraulic Fracture

Characterisation

Flow Assurance

Wellbore Integrity

Monitoring

X-Well Comms



Thank you

an introduction to fibre-optic distributed acoustic sensing...

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