michelclaverie orinoco heavyoil

Venezuela – Orinoco Heavy Oil Field Project UpdateIBC Energy Offshore Heavy Oil conference, 25-25 Nov. 2011

Michel ClaverieHead of Wireline Petrophysics DomainSchlumberger

PDVSA – Project Magna Reserva

Venezuela Orinoco Belt 27 blocks 18 220 km2Venezuela Orinoco Belt, 27 blocks, 18,220 km2

OIP 1360 billion barrels (1360 x109); Reserves 236 billion barrelsProject Magna Reserva: Reserves certification – volume distribution Project Magna Reserva: Reserves certification – volume, distribution and oil quality; hundreds of stratigraphic wells – Start August 2005 Target completion 2008g g p– 12 companies in partnership with PDVSAProject Orinoco: Optimization of production methodology and recovery; Limit water production

- Venezuela Orinoco Heavy Oil - Michel Claverie ,Schlumberger IBC Energy Offshore Heavy Oil conference, 24-25 Nov. 2011

Orinoco Heavy Oil – Formation Evaluation

Petrophysical challengesPetrophysical challengesFormation evaluation in heavy oil reservoirs

Elemental capt re spectroscop– Elemental capture spectroscopy– Magnetic resonance

Di l t i di i– Dielectric dispersionConclusions


Formation Evaluation Challenges

Prediction of water-free oil production zonesDifficult invasion analysis from multiple DOI resistivity logs

– Very little contrast between formation water (< 20,000 ppm) and mud filtrate (5000 ppm NaCl) at bottom hole temperature

– Very shallow invasionOil volume (saturation) alone does not predict water-cut

– A medium resistivity layer can produce either oil or watery y pNative oil can be 10,000 times more viscous than water

– Predict zones of potential water productionPredict zones of potential water production– Oil sampling very difficult


Field Development – Formation Evaluation IssuesIncreasingly complex reservoir conditions (stratigraphic wells away from blocks in production)

– Thinly bedded reservoirs, low resistivity pay– Fresh water, varying water salinities– Biodegraded oil, tar zones & mats– Oil reservoirs not at irreducible water saturation– Complex fluids distribution (water above oil)Oil viscosity & mobility (k/μ)y y ( μ)

– Formation permeability: 1 to 10 Darcies– Oil viscosity: >1,000 cP (up to 5,000 cP) @ 130degF / 1,300 psiy ( ) @ g

very low mobility– Currently, cold production @ 2,000 – 3,000 cP– Future areas; oil viscosity ~ 20,000 – 30,000 cP


Resistivity – “Dead Oil” vs. Producible Oil LayerNon-producible oil (by cold production) Producible oil

Resistivity profile and oil volume alone are insufficient to predict oil vs water productionResistivity profile and oil volume alone are insufficient to predict oil vs. water productionRef : Guzman-Garcia, SPWLA 2001


Accurate Formation Resistivity Accurate Reserves Estimate



Petrophysical challengesPetrophysical challengesUncertainty reduction in formation evaluation

El t l t t– Elemental capture spectroscopy– Magnetic resonance– Dielectric dispersionConclusionsConclusions


Elemental Capture GR Spectroscopy

D i ht l tDry weight elements:Si, Ca, Fe, S, Ti, GdMgAl K N

AmBe Source

BGO Crystal

6.6 ft6.6 ft

Al, K, Naand PMT

Boron Sleeve

Meas

ECS Mg Standard2008 MeasurementsMeas

ECS Mg Standard2008 Measurements

Elemental Concentrations

Arb

itrar

y Sc

ale) Calc

Arb

itrar

y Sc

ale) Calc

Cou

nts

(AC

ount

s (A

Improved statistical uncertainty

1 2 3 4 5 6 7 8Energy (MeV)

1 2 3 4 5 6 7 8Energy (MeV)

and accuracy of new Mg standard


Porosity, Resistivity & GR Spectroscopy. – Porosity, resistivity logs

. – GR spectroscopy Vclay, lith l d t i ti

A

Blithology and matrix properties

. – Combined petrophysical analysis of minerals and fluids volumes

CAminerals and fluids volumes

CB

C

Elemental Concentrations


Complex MineralogyKaolinite, illite, potassium feldspar and quartzThorium bearing minerals (zircon or monazite) that increase apparent GRincrease apparent GRGR spectroscopy superior to conventional GR for accurate clay volume


Geological Setting

Borehole Image &

Thin reservoir beds within

Borehole Image & GR Spectroscopy

Thin reservoir beds within shale sectionBasin gradually fills up with sediments, depositional energy is reduced oil found at lower resistivity valuesyApparently massive lower sandstone reservoir composed of two very distinct bodies of two very distinct bodies, deposited in different directions, under high energy

diticonditions




Elemental capture spectroscopy– Elemental capture spectroscopy

– Magnetic resonance– Dielectric dispersionConclusions


Magnetic Resonance & Fluids Properties

Surface Relaxation

Bulk Relaxation

BO Larger FieldSmaller Field

Echo

Echo

180°Pulse

Diffusion Relaxation

Echo Pulse


Magnetic Resonance & Fluids Properties

Oil Total T1Water

Surface Relaxation D-T2-T1 3D map

T2-T1 map

Oil Total T1WaterGas

T2-T1 map

Water

Gas Diffusion Coefficient

Bulk RelaxationD D

WaterDiffusion Coefficient

Viscosity-T2Correlation

BO Larger FieldSmaller Field

T2 T1T1

Correlation

Echo

Echo

180°Pulse

D-T2 map

Diffusion Relaxation

Echo Pulse


Magnetic Resonance Technology

Eccentered, gradient design M lti l i lt d th f Multiple, simultaneous depths of investigation (DOIs)Measurements taken beyond damaged zoney gRadial profiling of fluid saturations

High-resolution

Main antenna

antennas Permanent magnet

Santenna

N

S

N

S

B0B1

Antenna


Irreducible Water Saturation ?

(ms) (ms) (v/v) (v/v) (v/v)(ms)(ohmm)

(ohmm)2.7 in. 4.0 in.1.5 in.

2.7 in. 4.0 in.1.5 in.

Ref : Heaton, SPWLA 2007 Heavy Oil, Fresh Water, WBM - Venezuela Orinoco Heavy Oil - Michel Claverie ,Schlumberger IBC Energy Offshore Heavy Oil conference, 24-25 Nov. 2011

Irreducible Water Saturation


(ohmm)2.7 in. 4.0 in.1.5 in.

2.7 in. 4.0 in.1.5 in.

DOI = 1.5 in. DOI = 2.7 in.

cm2 s

-1)

10-2DOI = 4.0 in.

D(c

10-7

oil water

1 10000 1 10000 1 10000T1(ms)

Ref : Heaton, SPWLA 2007 - Venezuela Orinoco Heavy Oil - Michel Claverie ,Schlumberger IBC Energy Offshore Heavy Oil conference, 24-25 Nov. 2011

Irreducible Water Saturation

1.5 in. 2.7 in. 4.0 in.


(ohmm)DOI = 1.5 in. DOI = 4.0 in.DOI = 2.7 in.

m2 s

-1)

10-22.7 in. 4.0 in.1.5 in.

D(cm

10-7

oil

1 10000 1 10000 1 10000

water

T1(ms)

Ref : Heaton, SPWLA 2007 - Venezuela Orinoco Heavy Oil - Michel Claverie ,Schlumberger IBC Energy Offshore Heavy Oil conference, 24-25 Nov. 2011

Water Above Oil w/o Apparent Seal

Water above oil within clean sand w/o apparent sealapparent sealTar zones and mats create permeability p ybarriers


Estimating the Viscosity of Heavy Oils

φtotal

φNMR

φFree FluidφBound Fluid

φtotal

φsxo

φswirr

InvisibleHeavy Oil

VisibleHeavy Oil

Bound Water

FreeWater

VisibleLight Oil

φsxo

Oil T2 Cutoff

litud

e T2 Cutoff

HI-T2 viscosity correlation0.1 1 10 100 1000T2 (msec)

Am

pl

HI-T2 viscosity correlationAccurate at low viscositiesStable at high viscosities

NMR Log T2 Distribution in Oil Sand T2 (msec)

HI = fraction of visible porosityExtension to live oil

HI = NMR hydrogen index of oil

HI fraction of visible porosityT2 = NMR transverse relaxation

T2 = logarithmic mean T2 relaxation time (sec)α, β = empirically determined coefficientsRef : Badry, 2007


Oil ViscosityViscosity= 25,000 cP!

Ref.: Chengbing Liu, SPWLA 2007




Elemental capture spectroscopy– Elemental capture spectroscopy– Magnetic resonance

Di l t i di i– Dielectric dispersionConclusions


Dielectric Dispersion Measurements

Dielectric Dispersion

Shaly & Laminated SandsMicro-Resistivity1 1000

X-plot Porosity50 0

Shallow Water Porosity50 0Rw < Rmf

Rw > Rmf

Moved

ResidualSP0 100

GR0 150

Low resistivity / low contrast evaluationThin beds evaluationClay Cation Exchange Capacity log

Deep Resistivity1 1000 Deep Water Porosity50 00 20Salinity 0 Sw 1Caliper8 18

Heavy-oilFresh formation water evaluationDual depth of investigation - HC mobility

CarbonatesResidual HC volume - independent of RwRock texture – m Cementation Factor log


Dielectric Dispersion

Complex Permittivity:

εφ &

― water salinity

― water saturation wS

wppkrεσ

Measured Relative Permittivity ―

Measured Conductivity ―

mT εφ &

w


Dielectric Properties of Common Minerals & Fluids

Material Relative Dielectric Permittivity (unitless)

Quartz - SiO2 4.4Calcite CaCO3 8 5Calcite - CaCO3 8.5Dolomite - CaMg(CO3)2 6.8Dry Clay 5 1 to 5 8Dry Clay 5.1 to 5.8Air & Gas ~1Oil 2 to 2.4Pure water 80 to 45 (function of ω, T, P)Saline water (reservoir 60 to 40 (function of ω, T, Sal, temperature) P)

Sodium Chloride - NaCl 5.9References: Schlumberger


Thin Bedded Reservoirs

Micro-Resistivity1 1000

Hydrocarbon

DS Water Porosity50 0

Oil100

S li it

SP0

GR0 150 0 Sw Ait 1 1 1000Horizontal ResistivityDielectric-Scanner Deep Resistivity1 1000 X-plot Porosity50 00 Sw 1160 30

Salinity Caliper6 1 1000Vertical ResistivityStatic FMI Image

Dielectric shows thin

real time answer

XX10Dielectric shows thin beds and a lot more oil than Induction

XX10

XX15

Interpretation is fi d b FMI

XX20

confirmed by FMI images and with vertical and horizontal XX25

resistivities from Rt-Scanner XX30

Ref.: Venezuela – SPE-116130 (2008) - Venezuela Orinoco Heavy Oil - Michel Claverie ,Schlumberger IBC Energy Offshore Heavy Oil conference, 24-25 Nov. 2011

Variable Formation Water SalinityStandard logs

D R i ti it


D it P it

X-plot Porosity50 0

Neutron Porosity50 0

C li

SP0 100

GR0 150

Deep Resistivity1 1000 Density Porosity50 0Caliper6 16

X100

Moved Oil ?High deep resistivity and high porosity

X200

X300

Invasion from shallow resistivity X400

Heavy oilX500

X600

X700

X800

Water zoneX800

Ref.: Venezuela – SPE 2008 - Venezuela Orinoco Heavy Oil - Michel Claverie ,Schlumberger IBC Energy Offshore Heavy Oil conference, 24-25 Nov. 2011

Variable Formation Water SalinityDielectric Processing Micro-Resistivity1 1000

X-plot Porosity50 0


Salinity

Rw > Rmf

Moved

ResidualSP0 100

GR0 150g

Fresh water zone


X100

Deep zone salinity less than shallow zone.Deep zone salinity decreases with depth ( agrees with SP

X200

X300with depth ( agrees with SP deflection), hence the increase in resistivity X400

Heavy oil• Same saturation for deep

and shallow zones

X500

X600

Water zone Deep zone formation

l i h d

and shallow zonesX700

X800water saltier than mud X800


Saturation Profiling – Oil Producing Zones


X-plot Porosity50 0


Salinity

Rw > Rmf

Moved

ResidualSP0 100

GR0 150

Uniform saturation and moveable oil


volumeExcellent results even in

X100

results even in large hole

ResistivityX150

y– very sensitive to small

amount of clay– provides a misleading

i f i

X150

picture of saturation

X200


Oil vs. Water Producing ZonesInvasion processing in a heavy oil zone Micro-Resistivity1 1000

X-plot Porosity50 0


Rw > Rmf

Moved

ResidualSP0 100

GR0 150yDeep Resistivity1 1000 Deep Water Porosity50 00 20

Salinity 0 Sw 1Caliper8 18

Formation water X100Formation water saltier than mud

Oil displaced

Oil producing zone

X150

Formation water fresher than mud

Water producing zoneWater displaced

X200


Producible Oil vs. Tar Zones

X574ft: Oil X575 ft X574ft: Oil sample

X642 ft

X701 ft X701ft: Oil & Water sampleWater sample

X818 ft W t X818 ft: Water sample

Ref.: Mosse, SPWLA 2009




Elemental capture spectroscopy– Elemental capture spectroscopy– Magnetic resonance

Dielectric dispersion– Dielectric dispersion

Conclusions


Conclusions – Challenges & Solutions forO i H Oil R iOrinoco Heavy Oil Reservoirs

Fresh formation waterV i bl t li it ( il l )– Variable water salinity (oil volume)

– Silty or thin bed intervals (oil volume)H ( i ) ilHeavy (viscous) oil– Oil or water producible phase (oil cold production)

Tar zones and mats (permeability barriers anomalous fluid sequences)– Tar zones and mats (permeability barriers, anomalous fluid sequences)– Variable viscosity profile (without sample)Mineralogy and geological settingMineralogy and geological setting– Radioactive & heavy minerals (clay volume, porosity)– Variable environment of deposition (reservoir quality)p ( q y)Other formation & fluid properties (not presented)– Unconsolidated sands (wellbore stability HZ wells, sand production)( y , p )– Hydrocarbon samples (viscosity, composition)


Sonic - Unconsolidated Formations

Unconsolidated sandsWellbore stability HZ wellsP t ti l d d tiPotential sand production

Very slow Compressional & Shear Compressional & Shear sonic transit times


michelclaverie orinoco heavyoil

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