NORTHWEST ST PI PICEANCE CREEK BASI SIN HYDROGEOLOGY Colorado - - PowerPoint PPT Presentation

copyrig ight 2010, Sh Shell ll Explo loratio ion and Pr Productio ion Co., and it its affi filia liates

NORTHWEST ST PI PICEANCE CREEK BASI SIN HYDROGEOLOGY

Colorado School of Mines Colorado Energy Research Institute 30th Oil Shale Symposium October 18-22, 2010

Michael Day2, Erik Hansen1, Terry Gulliver2, Bill Mckinzie3

1 – Shell Exploration & Production Co.; 2 – Norwest Corp.; 3 – Retired Shell Exploration & Production Co.

copyrig ight 2010, Sh Shell ll Explo loratio ion and Pr Productio ion Co., and it its affi filia liates 2 October r 20, 2010

Introduction

Historical Background

n Piceance Creek Basin (PCB) hydrogeology studied previously

n Emphasis starting in late 1960’s and early 1970’s

n Groundwater plays a vital role in oil shale development

n Mining, in situ retorting, in situ conversion (ICP) thermal

n Shell has installed >300 wells, obtained ~80 cores, taken >5,000 water

level measurements, obtained >8,000 analytical samples, conducted >1,000 packer permeability tests, performed >300 pumping stress tests, and developed a PCB regional numerical flow and transport model and numerous project-specific, local models

n Starting with SIFT near Piceance Creek and Horse Draw mine (70’s) n Red Pinnacle (southern rim) 80’s n Shell Mahogany fee property pilots, MFE, MDP Original, Deep Heater Test, MDP South

(90’s – 2007), MIT (‘04-’05,) FWT (’05 – present)

n Federal PLA/RD&D and surrounding area (2000 – present)

Results of Shell Investigations (this presentation)

n Discussion of data gathered from hydraulic testing, geochemistry and

isotopes

n Designation of hydrostratigraphy n Development of numerical flow and transport model

copyrig ight 2010, Sh Shell ll Explo loratio ion and Pr Productio ion Co., and it its affi filia liates 3 October r 20, 2010

Shell and Other Hydrology Wells in the Piceance Creek Basin

copyrig ight 2010, Sh Shell ll Explo loratio ion and Pr Productio ion Co., and it its affi filia liates 4 October r 20, 2010

Shell and Other Hydrology Wells in Fee and PLA Areas

copyrig ight 2010, Sh Shell ll Explo loratio ion and Pr Productio ion Co., and it its affi filia liates 5 October r 20, 2010

Piceance Creek Basin Topography & Features

Cross- Section Location Yellow Creek Piceance Creek White River Elevation, ft msl (feet) Faulting

FWT MIT MDP C-a Tract Shell North PLA Yellow Creek PLA Shell East PLA

General upper GW flow direction (L7/ L6/L5)

6 copyrig ight 2010, Sh Shell ll Explo loratio ion and Pr Productio ion Co., and it its affi filia liates October r 20, 2010

USGS Work

• N. Piceance Basin Plan View

Water generally flows from the edge of the basin to the creek drainages

Up Flow lower aquifer to upper aquifer – model output Extend of Faults / Fracturing

Fig igures from: m: Robson, S.

• S. G.; Sa

Sauln lnie ier, G. J., Jr.; 1981 Hydrogeochemis mistry and simu imula lated solu lute tr trans nspor

• rt,

t, Pic Picea eanc nce Ba Basin, in, nor northw hwes ester ern Color

• lorado

USG SGS S Pr Professio ional l Paper r 1196

copyrig ight 2010, Sh Shell ll Explo loratio ion and Pr Productio ion Co., and it its affi filia liates 7 October r 20, 2010

Basin Litho-Stratigraphy & USGS Hydrology Units

n

R7 Mahogany (thought by USGS to be a very good “seal”) separates Upper from Lower Aquifer Units

n

Heads and geochemistry support a different division discussed later

3000 4000 5000 6000 7000 8000 9000 5 10 15 20 25 30 Distance (Miles) Elevation (AMSL)

Topo R7 R5 L2 Nahc

Saline Zone (nahcolite) No Flow Lower Aquifer Unit

(B-G -> L3)

Upper Aquifer Unit

(Uinta and A-G)

Piceance Creek White River

?

MDP MIT

Shell Fee

C-a Tract

Federal RD&Ds, PLAs

Faults Known Potential

copyrig ight 2010, Sh Shell ll Explo loratio ion and Pr Productio ion Co., and it its affi filia liates 8 October r 20, 2010

Summary of Shell Baseline Characterization Tests and Measurements

Core holes ¡ 80 ¡ Groundwater monitoring wells ¡ 348 bedrock wells (cased to top & drilled out to base of open interval) ¡ Alluvial monitoring wells ¡ 13 ¡ Single well pumping tests ¡ 300, ~ 6-8-hour ¡ Multi well pumping test ¡ 27 tests over 3 sites, up to 72 hr ¡ Multi packer slug tests ¡ 1,087, mostly 10 and 20 ft intervals ¡ Injection fall-off tests w/ packers ¡ 61 ¡ Water Level measurements ¡ 5,862 ¡ Bedrock water quality analyses ¡ 8,680 (minimum 5 quarters / well) ¡ Alluvial water quality analyses ¡ 149 (up to 5 quarters / well) ¡

10 10’ 10 10’ Te Test Zo Zone 10 10’ XD4 XD4 XD2 XD2 XD3 XD3 XD1 XD1 Packer r 4 Packer r 3 Packer r 2 Packer r 1

Packer r assemb mbly

copyrig ight 2010, Sh Shell ll Explo loratio ion and Pr Productio ion Co., and it its affi filia liates 9 October r 20, 2010 Lean, Fracture Oil Shale => Water Bearing Intervals ??? Rich, Less Fracture Oil Shale => “Seals” ???

Rich and Lean Oil Shale

n Lean, highly fractured oil shale results in saturated water bearing

interval or aquifer

n Nahcolite dissolution also results in L4 and L3 water bearing intervals

n Rich, less fractured oil shale results in aquitard or “seal” –

Generally, but is variable relative to the up-scaled R & L zones and will include exceptions . . .

~5 f ~5 ft

copyrig ight 2010, Sh Shell ll Explo loratio ion and Pr Productio ion Co., and it its affi filia liates 10 10 October r 20, 2010

Hydraulic Conductivities of WBIs

n Approximate log-normal transmissivities n L3 distribution reflects nahcolite presence or dissolution

20 40 60 80 100 Log Transmissivity, L2/T Cumulative % <

UT L7 BG L5 L4 L3

nahcolite largely ¡not ¡dissolved

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Geochemistry of the WBIs

n L3 and L4 have very low Ca & Mg with a spread of Na; low sulfate; spread in alkalinity n UT, L7, L6 and L5 (and AL) have low Na and spread of Ca & Mg; large spread in

sulfate; similar alkalinity (L5 is somewhat transitional)

100 10,000 1,000,000 50 100 150 200 250

Ca + Mg, mg/L Na, mg/L

UT L7 L6 L5 L4 L3

200 400 600 10 100 1,000 10,000 100,000

Alkalinity (as CaCO3) mg/L Sulfate, mg/L

12 12 copyrig ight 2010, Sh Shell ll Explo loratio ion and Pr Productio ion Co., and it its affi filia liates October r 20, 2010

Shell Piceance

Creek Basin Hydrogeology

Shell separates upper from lower at the R5 Seal

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Shell PCB Hydrogeology Cross-Section (location above)

n Uinta, upper Parachute Ck, and lower Parachute Ck are major WBIs

3000 4000 5000 6000 7000 8000 9000 5 10 15 20 25 30 Distance (Miles) Elevation (AMSL)

Topo R7 R5 L2 Nahc

Saline Zone (nahcolite) No Flow

Piceance Creek White River ? MDP MIT

Shell Fee

C-a Tract

Federal RD&Ds, PLAs

Faults Known Potential

?

L3 L4 R4 R5

?

L5 L6 R6

Upper Parachute Creek WBIs

R7 L7

Uinta WBIs

R8

Lower Parachute Creek WBIs

copyrig ight 2010, Sh Shell ll Explo loratio ion and Pr Productio ion Co., and it its affi filia liates 14 14 October r 20, 2010

Numerical Flow Model Domain

n About 600 square

miles

n Rotated to align

with major and minor anisotropic hydraulic conductivity seen in some layers

n Natural no-flow or

general head boundaries

Model l doma main in and rotatio ion

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Boundary Conditions and Water Balance

n 567,600 acres of N.

Piceance Creek drainage basin

n Base flow recharge

calculation (Dec – Feb)

n Recharge = Discharge

(Stream Base Flow + Alluvial Underflow + % Spring Discharge)

n Evapotranspiration

assumed minimal Boundary Condit itio ions Water r Bala lance

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Model Groundwater Recharge Distribution

n Correlates with topography

n Areal distribution calibrates as well as alluvium-focused recharge

A A’

Location of next slide cross-section

copyrig ight 2010, Sh Shell ll Explo loratio ion and Pr Productio ion Co., and it its affi filia liates 17 17 October r 20, 2010

Numerical Model Input and Layering

n Layering based upon

Shell defined hydrostratigraphy

n Model uses average

parameters from field tests as starting point

n Values modified

during model calibration with

• bserved heads and

base flow discharges

n TDS “source” above

background in upper WBIs near discharge features such as Piceance Creek assumed due to nahcolite dissolution

Layer Hydrostratigraphic Zone Comments 1 Alluvium and Uinta Made inactive where dry cells occur 2 Upper Uinta Made inactive where dry cells occur 3 Lower Uinta 4 R8 Seal unit between Uinta and Upper Parachute Creek 5 L7 “A-Groove” 6 R7 “Mahogany” Regional Seal unit 7 L6 “B-Groove” 8 R6 9 L5 10 R5 Regional Seal unit 11 Upper L4 L-4 unit split due to thickness (>300 ft) 12 Lower L4 13 R4 14 L3 15 R2/GG/DC Seal unit between Lower Parachute Creek and Wasatch 16 Wasatch Set to 1000 ft thick uniformly. Lower sink.

¡

SW to NE Conductivity/Layering A A’

copyrig ight 2010, Sh Shell ll Explo loratio ion and Pr Productio ion Co., and it its affi filia liates 18 18 October r 20, 2010

L7 WBI Potentiometric Head – Measured vs. Modeled

Model calibration statistics are within accepted ranges (stream discharge, mass balance error < 1%, 225 simulated vs. observed head normalized root mean squared <10%, correlation coefficient ~0.95)

copyrig ight 2010, Sh Shell ll Explo loratio ion and Pr Productio ion Co., and it its affi filia liates 19 19 October r 20, 2010

Transport Modeling

N

copyrig ight 2010, Sh Shell ll Explo loratio ion and Pr Productio ion Co., and it its affi filia liates 20 20 October r 20, 2010

Conclusions

n Significant amount of work has been beneficial to Shell’s

understanding of the hydrogeology and its associated effects on

• il shale development projects

n Hydraulic testing, geochemistry and isotopes resulted in 6 main

water bearing intervals monitored

n Major division across the R5 from overlying Ca-Mg to

underlying Na composition

n Numerical model has also been very useful in analyzing various

project scenarios

n

Acknowledgements

n Co-authors n Shell Exploration & Production Co. co-workers n Others at Norwest Corp. n Gerald Daub, Daub and Associates