DOE GeothermalProgram Briefing

March 20, 2003March 20, 2003Earth Sciences DivisionEarth Sciences Division

Lawrence Berkeley National LaboratoryLawrence Berkeley National Laboratory

Mack KennedyMack Kennedy

Geothermal Energy ProgramLawrence Berkeley National Laboratory

MissionMission: Develop and integrate state of the art scientific : Develop and integrate state of the art scientific methods to assist industry in finding, characterizing, and methods to assist industry in finding, characterizing, and producing geothermal fields.producing geothermal fields.

Core StrengthsCore Strengths Reservoir EngineeringReservoir Engineering Geophysics (Seismic, EM, MT, Remote Sensing)Geophysics (Seismic, EM, MT, Remote Sensing) Isotope GeochemistryIsotope Geochemistry Rock MechanicsRock Mechanics GeologyGeology

Lawrence Berkeley National Laboratory

Programmatic Goals Addressed by LBNL’s Geothermal Programmatic Goals Addressed by LBNL’s Geothermal ProgramProgram Resource ExpansionResource Expansion

Advance fundamental understanding of geothermal Advance fundamental understanding of geothermal systemssystems

Advance reservoir characterization technologiesAdvance reservoir characterization technologies Resource assessmentResource assessment

ExplorationExploration Evaluate and develop new innovative techniquesEvaluate and develop new innovative techniques Reduce drilling costs – improved well-sitingReduce drilling costs – improved well-siting

Lawrence Berkeley National Laboratory

CollaborationsCollaborations IndustryIndustry: Calpine; Caithness; Unocal; Exxon-Mobil; CalEnergy; : Calpine; Caithness; Unocal; Exxon-Mobil; CalEnergy;

EMI; EPDC, JapanEMI; EPDC, Japan GovernmentGovernment: USGS; LLNL; SNL; INEEL: USGS; LLNL; SNL; INEEL AcademicAcademic: EGI, Univ. of Utah; Univ. of Nevada, Reno; UC : EGI, Univ. of Utah; Univ. of Nevada, Reno; UC

Berkeley; Stanford; New Mexico Tech.; Ohio State Univ.; Berkeley; Stanford; New Mexico Tech.; Ohio State Univ.; Southern Methodist Univ.Southern Methodist Univ.

AccomplishmentsAccomplishments Publications in Refereed Journals (2001 – Present) -- 25Publications in Refereed Journals (2001 – Present) -- 25 Conference Abstracts/Presentations (2001 – Present) -- 25Conference Abstracts/Presentations (2001 – Present) -- 25

Lawrence Berkeley National Laboratory

Research ProgramsResearch Programs

Geothermal Reservoir Dynamics ($375K)Geothermal Reservoir Dynamics ($375K)

Geophysical Methods for Resource Exploration and Geophysical Methods for Resource Exploration and Monitoring ($265K)Monitoring ($265K)

Innovative Geothermal Exploration Techniques Innovative Geothermal Exploration Techniques ($260K)($260K)

Lawrence Berkeley National Laboratory

Geothermal Reservoir DynamicsGeothermal Reservoir Dynamics

Reservoir Modeling Reservoir Modeling ($195K, K. Pruess)($195K, K. Pruess)

Isotope and Geochemical Studies Isotope and Geochemical Studies ($100K, M. Kennedy, ($100K, M. Kennedy, M. Lippman, with A. Truesdell)M. Lippman, with A. Truesdell)

Technical Programmatic Assistance Technical Programmatic Assistance ($80K, M. ($80K, M. Kennedy, M. Lippmann)Kennedy, M. Lippmann)

Geothermal Reservoir Dynamics

Reservoir ModelingReservoir Modeling

ObjectiveObjective: Enhance and apply reservoir simulation codes: Enhance and apply reservoir simulation codes

Multi-phase fluid and heat flowMulti-phase fluid and heat flow Rock-fluid interaction, including mineral precipitation, Rock-fluid interaction, including mineral precipitation,

dissolution, and rock mechanicsdissolution, and rock mechanics Behavior of phase partitioning tracers in geothermal systems.Behavior of phase partitioning tracers in geothermal systems.

Reservoir Modeling

TOUGHREACTTOUGHREACT TOUGH2 coupled to a fully-featured reaction path code and thermodynamic databaseTOUGH2 coupled to a fully-featured reaction path code and thermodynamic database Multiphase fluid and heat flow, plus rock-water-gas chemistryMultiphase fluid and heat flow, plus rock-water-gas chemistry

TOUGH-FLACTOUGH-FLAC TOUGH2 coupled to commercial rock mechanics code FLAC3DTOUGH2 coupled to commercial rock mechanics code FLAC3D Non-isothermal stress-strain analysis, with porosity and permeability changeNon-isothermal stress-strain analysis, with porosity and permeability change Movement along faults and fracturesMovement along faults and fractures Uplift due to episodes of magmatic activity and degassingUplift due to episodes of magmatic activity and degassing Injection response, growth of EGS reservoirInjection response, growth of EGS reservoir

TOUGH2/EOSNTOUGH2/EOSN Fluid property module for noble gases and saline brines (including non-saline water)Fluid property module for noble gases and saline brines (including non-saline water) Realistic temperature dependence of noble gas solubility and diffusivitiesRealistic temperature dependence of noble gas solubility and diffusivities Design and analysis of tracer tests (natural or introduced)Design and analysis of tracer tests (natural or introduced)

TOUGH2 SYMPOSIUMTOUGH2 SYMPOSIUM May 12-14, 2003May 12-14, 2003

Fluid Flow and Diffusion in Fractured-Porous Medium

The lighter noble gasesThe lighter noble gases Partition more strongly into the gas (vapor) phasePartition more strongly into the gas (vapor) phase Have larger diffusivityHave larger diffusivity Have stronger diffusive exchange with the rock matrixHave stronger diffusive exchange with the rock matrix

As a consequence, the lighter noble gases have…As a consequence, the lighter noble gases have… Slower peak arrivalSlower peak arrival Reduced peak concentrationsReduced peak concentrations Stronger tailsStronger tails

rock matrix

fracture

fluid flow

tracer diffusion

A Measure of Fracture Spacing

0

20

40

60

80

100

120

140

0 10 20 30 40 50 60

FS (m)

Tim

e (d

ay)

0.000

0.002

0.004

0.006

0.008

0.010

0.012

0.014

0.016

0.018

Rel

ativ

e P

eak

Val

ue

Relative peak value

Decay time

Peak time

Increased fracture spacing...

reduces fracture-matrix reduces fracture-matrix interactioninteraction

accelerates peak arrivalaccelerates peak arrival increases peak increases peak

concentrationsconcentrations accelerates decay of tailaccelerates decay of tail

Geothermal Reservoir Dynamics

Isotope and Geochemical StudiesIsotope and Geochemical Studies

ObjectiveObjective: Baseline isotope and geochemical data sets : Baseline isotope and geochemical data sets in preparation for monitoring injection to enhance in preparation for monitoring injection to enhance production.production.

NW Geysers (Aidlin and Ottoboni Ridge)NW Geysers (Aidlin and Ottoboni Ridge) Coso EGS ProjectCoso EGS Project

Technical Programmatic AssistanceTechnical Programmatic Assistance

Geophysical Methods for Resource Exploration and Monitoring

Seismic Imaging Seismic Imaging ($175K, E. Majer)($175K, E. Majer) Electromagnetic Imaging Electromagnetic Imaging ($30K, K-H. Lee)($30K, K-H. Lee) Integrated Seismic and EM Imaging Integrated Seismic and EM Imaging ($30K, E. ($30K, E.

Majer, K-H. Lee)Majer, K-H. Lee) Geodetic Imaging Geodetic Imaging ($30K, D. Vasco)($30K, D. Vasco)

3-D Seismic Imaging of Geothermal Reservoirs

Shot No. 2

Program Goals Program Goals Detection & Mapping of Fluid PathsDetection & Mapping of Fluid Paths

Work ObjectivesWork Objectives Adaptation and Application of Modern Adaptation and Application of Modern

3-D Seismic Imaging for Reservoir 3-D Seismic Imaging for Reservoir DefinitionDefinition

Work ScopeWork Scope 3-D Seismic Field Data Acquisition3-D Seismic Field Data Acquisition State-of-the-Art Data ProcessingState-of-the-Art Data Processing 3-D Numerical Modeling3-D Numerical Modeling Integrated Seismic with other Integrated Seismic with other

Geophysical Field DataGeophysical Field Data AccomplishmentsAccomplishments

Seismic Studies at Rye Patch CompletedSeismic Studies at Rye Patch Completed Numerical Modeling of Fractured Numerical Modeling of Fractured

Reservoir Initiated for Field DesignReservoir Initiated for Field Design

Model Data

Fracture Events

Geophysical Methods for Resource Exploration and Monitoring

Electromagnetic ImagingElectromagnetic Imaging

ObjectiveObjective: Develop efficient numerical inversion codes for : Develop efficient numerical inversion codes for mapping high-permeability zones using single-hole EM data in 3-mapping high-permeability zones using single-hole EM data in 3-D.D.

Complete inversion codes for analyzing 3-D electrical Complete inversion codes for analyzing 3-D electrical structures in the vicinity of a boreholestructures in the vicinity of a borehole

Analyze data acquired with the Geo-BILT (EMI), Dixie Valley Analyze data acquired with the Geo-BILT (EMI), Dixie Valley field testfield test

Conduct field test in The Geysers.Conduct field test in The Geysers.

TransmitterElectronics

3-Component Transmitter

3-Component Receiver, 2m

3-Component Receiver, 5m

Geo-BILT System

• Induction coils:– 3 component inductive source

– Two 3-component inductive receivers spaced 2 and 5 meters

• Operates at four frequencies: 2, 6, 16 and 42 kHz

• Operating conditions: 260 C, 5 kmReceiverElectronics

EMI (Schlumberger)

Northing Easting

Resistivity(Ohm-m)

-2 0 0 2 0

-1 8 0 0

-1 7 0 0

-1 6 0 0

-1 5 0 0

-1 4 0 0

1 .2

1 .4

1 .6

1 .8

2

2 .2

2 .4

2 .6

2 .8

3

3 .2

3 .4

3 .6

-2 0 0 2 0

-1 8 0 0

-1 7 0 0

-1 6 0 0

-1 5 0 0

-1 4 0 0

1 .2

1 .4

1 .6

1 .8

2

2 .2

2 .4

2 .6

2 .8

3

3 .2

3 .4

3 .6

ft

Comparison of 3-D Inversions ofSingle-hole EM Data

Finite-difference

Integral equation

Imaging Geothermal Reservoir Dynamics using High Resolution Satellite Observations

Program Goals:Program Goals: Advance understanding of reservoir dynamics.Advance understanding of reservoir dynamics. Enhance geothermal recoveryEnhance geothermal recovery

Objectives:Objectives: Develop techniques and software for imaging of reservoir dynamicsDevelop techniques and software for imaging of reservoir dynamics Applications to existing and potential geothermal fieldsApplications to existing and potential geothermal fields

Budget:Budget: LBNL 30KLBNL 30K LLNL 150KLLNL 150K

Organization and Personnel:Organization and Personnel: Don Vasco (LBNL) – Software development, application to geothermal fieldsDon Vasco (LBNL) – Software development, application to geothermal fields Bill Foxall (LLNL) - InSAR imaging, interpretationBill Foxall (LLNL) - InSAR imaging, interpretation Charles Wicks (USGS) – InSAR data reduction and processingCharles Wicks (USGS) – InSAR data reduction and processing

Accomplishments:Accomplishments: 2001 – Application to Coso geothermal field, publication in Geophysical Journal2001 – Application to Coso geothermal field, publication in Geophysical Journal 2002/2003 – Application to Dixie Valley geothermal field2002/2003 – Application to Dixie Valley geothermal field

Space-borne synthetic aperture radar

Image deformation overgeothermal reservoir

Constrain reservoir dynamics

Imaging Geothermal Reservoir Dynamics using HighResolution Satellite Observations

InnovativeGeothermal Exploration Techniques

ObjectiveObjective: Evaluate and develop new techniques for assessing existing : Evaluate and develop new techniques for assessing existing and finding new “hidden” geothermal systemsand finding new “hidden” geothermal systems..

Integrated approach calling on core LBNL scientific strengths: reservoir Integrated approach calling on core LBNL scientific strengths: reservoir engineering, geophysics, isotope geochemistry, geology, and remote sensing.engineering, geophysics, isotope geochemistry, geology, and remote sensing.

Active ProjectsActive Projects::

Soil gas signatures of hidden systems Soil gas signatures of hidden systems ($15K, C. Oldenburg, A. Unger)($15K, C. Oldenburg, A. Unger) Isotope geochemistry Isotope geochemistry ($165K, M. Kennedy)($165K, M. Kennedy) 3-D magnetotellurics 3-D magnetotellurics ($30K, M. Hoversten)($30K, M. Hoversten) Feasibility studies and technical oversight Feasibility studies and technical oversight ($50K. M. Kennedy)($50K. M. Kennedy)

• e.g. Moderate to high temperature He.g. Moderate to high temperature H22 extraction from organics extraction from organics

Soil Gas Signatures of Hidden Geothermal Systems

Objective: Use coupled subsurface-surface layer modeling to predict expected

locations and strength of maximum surface gas concentrations from a sub-surface source.

Model Development:

T2CA

(TOUGH2, CO2, Air with atmospheric dispersion capability).

Preliminary T2CA Results

Kilauea 3-D MT Imaging Experiment

Program Goals Program Goals Detection & MappingDetection & Mapping ExplorationExploration Reservoir diagnosticsReservoir diagnostics

Work ObjectivesWork Objectives Push software & hardware development Push software & hardware development

for fully 3D electrical structure mappingfor fully 3D electrical structure mapping Demonstrate geophysical integration in Demonstrate geophysical integration in

complex 3D hydrothermal environmentcomplex 3D hydrothermal environment Work ScopeWork Scope

Field data acquisitionField data acquisition 3D numerical modeling3D numerical modeling Integrated data interpretationIntegrated data interpretation

Budget (combined LBNL & SNL)Budget (combined LBNL & SNL) $80K 2002$80K 2002 $80K 2003$80K 2003

Organization & personnelOrganization & personnel LBNL (lead) LBNL (lead) G. M. Hoversten

Planning, survey data interpretationPlanning, survey data interpretation SNL SNL G. A. Newman

Massively Parallel modelingMassively Parallel modeling USGS USGS Jim Kauahikaua

Field support, data interpretationField support, data interpretation EMI EMI Nestor Cuevas

Data acquisition systems, support Data acquisition systems, support personnelpersonnel

AccomplishmentsAccomplishments 2002 40 site MT acquisition2002 40 site MT acquisition 2002 AGU paper2002 AGU paper Imaging of rift zones and magma conduit to Imaging of rift zones and magma conduit to

the mantelthe mantel Demonstrated consistency with seismic and Demonstrated consistency with seismic and

gravity interpretationsgravity interpretations Demonstrated large scale 3D numerical Demonstrated large scale 3D numerical

modeling and inversionmodeling and inversion

Depth & location of Vp/Vs Depth & location of Vp/Vs anomaly (Dawson et al.) ties to anomaly (Dawson et al.) ties to high conductivity beneath high conductivity beneath southern Kilauea calderasouthern Kilauea caldera

high fracturing and/or partial high fracturing and/or partial meltmelt

Resistivity image delineates Resistivity image delineates melt zones in rift systemmelt zones in rift system

Temperature distribution can be Temperature distribution can be inferred from conductivityinferred from conductivity

Program demonstrates that high Program demonstrates that high quality 3D imaging can be done quality 3D imaging can be done in hydrothermal areas in the in hydrothermal areas in the presence of rough topography presence of rough topography and complex structureand complex structure

First Pass 2D Conductivity Structure

North

Isotope Geochemistry

Objective: Conservative noble gases as tracers for studying fluid processes and heat and sources in geothermal systems.

• Locate and define the extent of hidden geothermal systems – Basin and Range, Cascades

• Reassessment of geothermal potential

• Sensitive tracers for monitoring injectate

• Enhance reservoir simulation models

Dixie Valley – Heat and Fluid Sources

DV Reservoir: 0.7-0.8 Ra

Dixie ValleyHelium Abundances and Isotopic Compositions:

Evidence for a Single Deep Fluid

F(4He)

0 50 100 150 200 250

R/R

a

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

DVGF

66-21

27-3246-32

45-14

Sou Spr

Hyder Spr

GW

Senator Fum

Senator's Toe

SE Fum

??

36-14

(230)

(197)

(195)

(160)

(165)

System must have at least two fluids:

•Young groundwater: F(4He) < 10; R/Ra < 0.4

•Fluid indistinguishable from geothermal production fluids: F(4He) > 150-200; R/Ra > 0.8

Common deep fluid suggests presence of larger exploitable resource.

Lawrence Berkeley National Laboratory

Future ObjectivesFuture Objectives – Well coordinated integrated collaborative field projects involving – Well coordinated integrated collaborative field projects involving Industry, National Laboratories, Universities, and the USGSIndustry, National Laboratories, Universities, and the USGS

Resource ExpansionResource Expansion Reliable high resolution remote fracture mappingReliable high resolution remote fracture mapping Couple mechanical properties and local stress to stimulated fracture geometries Couple mechanical properties and local stress to stimulated fracture geometries

and permeabilityand permeability Geometry and scale of fluid-rock exchange – thermal and chemicalGeometry and scale of fluid-rock exchange – thermal and chemical Improved drilling technologies – smart drilling, high temperatureImproved drilling technologies – smart drilling, high temperature

Exploration Exploration Reassessment of geothermal potentialReassessment of geothermal potential Improved understanding of geothermal systems – Basin and RangeImproved understanding of geothermal systems – Basin and Range Ground truth assessment of remote sensing techniquesGround truth assessment of remote sensing techniques

Geophysical Methods for Resource Exploration and Monitoring

Seismic ImagingSeismic Imaging

ObjectiveObjective: Extend and adapt multi-component 3-D and 4-D : Extend and adapt multi-component 3-D and 4-D seismic imaging to identify and separate geologic heterogeneity seismic imaging to identify and separate geologic heterogeneity and fracture controlled fluid pathways in geothermal reservoirs.and fracture controlled fluid pathways in geothermal reservoirs.

Develop 3-D models of elastic wave propagation in Develop 3-D models of elastic wave propagation in fractured/heterogeneous reservoirsfractured/heterogeneous reservoirs

Integrate surface and borehole seismic imaging methods and Integrate surface and borehole seismic imaging methods and modelsmodels

Evaluate cost effectiveness of single vs. multi-component and Evaluate cost effectiveness of single vs. multi-component and VSP vs. surface seismic imaging methods.VSP vs. surface seismic imaging methods.

Geophysical Methods for Resource Exploration and Monitoring

Integrated Seismic and EM ImagingIntegrated Seismic and EM Imaging

ObjectiveObjective: Integrate seismic and EM imaging technologies for optimum : Integrate seismic and EM imaging technologies for optimum mapping of geothermal reservoirs.mapping of geothermal reservoirs.

Develop an interactive iterative process using velocity structure, Develop an interactive iterative process using velocity structure, electrical conductivity structure, borehole log, and core analysis for electrical conductivity structure, borehole log, and core analysis for optimum interpretation imaging data.optimum interpretation imaging data.

Geodetic ImagingGeodetic Imaging

ObjectiveObjective: Evaluate and develop techniques using observations of surface : Evaluate and develop techniques using observations of surface deformation to image reservoir dynamics associated with fluid production.deformation to image reservoir dynamics associated with fluid production.

Combine high resolution InSAR, GPS, leveling, and tilt meter Combine high resolution InSAR, GPS, leveling, and tilt meter observations: Dixie Valley, Coso, and perhaps Long Valley.observations: Dixie Valley, Coso, and perhaps Long Valley.

Collaborative effort with LLNLCollaborative effort with LLNL