SPE-174119

SPE-174119-MSWater Management for Tight and Shale Reservoir:

A Review of What Has Been Learned and What Should Be Considered for Development in

Argentina

Juan Carlos Bonapace, Halliburton

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SPE-174119-MS • Water Management for Tight and Shale Reservoir: A Review of What Has Been Learned and What Should Be Considered for Development in Argentina • Juan Carlos Bonapace

• Introduction

• Sources of Water

• Stimulation Treatments and Fluid Systems

• Water Logistics

• Use and Reuse Non Traditional Waters

• Clay Inhibition

• Fracturing Fluid

• Review of New frac fluids – Tight Gas application (Reohology) - Damage (pH)

• Conclusions

Agenda

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IntroductionHydraulic Fracture in Argentina•Oil and Gas reservoir since 1960•Conventional, Tight and Shale•Depth, 300 to 4,500 m•BHT, 100 to 300F•Reservoir pressure, subnormal to overpressure•Fm permeability, high, medium, low, and ultralow perm•Multilayer reservoir and multitarget wells•Oil-based systems, alcohol-water mixtures, foams, and water-based fluids currently used

Experiences •2004 Tight Gas, primarily in Neuquina basin. Others jobs were performed in Cuyana and more recently in GSJ basins.•2010 Shale, primarily in Neuquina basin with other exploration wells in Cuyana and GSJ basins•More than 100 wells (> 500 hydraulic fracture)


Basin & FmReservoir

Neuquina Cuyana G.San Jorge

TightLajas

Punta RosadaMulichinco

Potrerillo D-129

ShaleLos Molles

Vaca MuertaAgrio

Cacheuta D-129

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Sources of WaterSources of Water•Fresh water, rivers, lakes, water wells•Used for conventional reservoirs development

Particular Cases (shale)•Los Molles, a mixture of fresh water (85%) and produced water (15%) was used for hydraulic fracture (10 stages) in a horizontal well.•D-129, operator decided to use 100% produced water (low salinity < 10,000 TDS) for 5 hydraulic fracture in a vertical well

Neuquina Basin (Unconventional) •Primary sources of water are rivers, Limay, Neuquén and Colorado).•Other sources are lakes as Cerro Colorado and Pellegrini•Groundwater sources, wells with low salinity (< 5,000 TDS), need a permit from regulatory authority and water is not suitable for human consumption or farmlanding.


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Stimulation Treatments and Fluid Systems

Sources of fresh water•Limay , Neuquén, Colorado river•Water wells in differents fields

Water Requirements•Values for water to use in fracturing fluids

Water characteristics•Underground water sources have higher values in terms of pH, sulphates, TDS, total suspended solids (TSS), chlorides, bicarbonates, and sodium.

Physical-Chemical Analysis - (Fresh Water)


Area South South South West West West West East EastGroup of Wells C C D D H H H S XType Water River (Limay) River (Limay) River (Nqn) River (Nqn) Well #1 Well #2 Well #3 River (Colorado) River (Colorado)Specific gravity 1.000 1.000 1.000 1.000 1.000 1.000 1.000 1.000 1.003pH 6 to 8 7.71 7.44 8.11 8.03 9.14 8.73 8.71 7.77 7.56Resistiviy (ohms-cm) 59.551 17.346 3.525 1.012 3.331 2.450 2.618 0.633 0.785Temperatura (°C) 15 to 40 24.4 24.5 21.0 20.7 20.6 19.9 20.4 22.9 23.2

Carbonate (mgL) < 600 0 0 0 0 0 7.2 14.4 0 0Bicarbonate (mgL) < 600 67.1 54.9 158.7 268.5 278.2 244.1 258.7 585.8 561.3Chloride (mgL) < 30,000 2.0 10.0 620.2 80.0 348.1 428.2 372.2 1,450.6 1,660.1Sulfate (mgL) < 500 7.5 155.0 50.0 85.0 475.0 650.0 625.0 1,750.0 1,750.0Calcium (mgL) 50 to 250 1.6 48.1 34.7 83.4 8.0 1.6 0.0 1,002.0 1,202.4Magnesium (mgL) 10 to 100 2.0 9.7 8.1 17.5 1.0 1.0 1.0 170.2 170.2Barium (mgL) 0 0 0 0 0 0 0 0 0Strontium (mgL) 0.02 0.02 1.3 1.2 n/a n/a n/a 10.08 11.40Total Iron (mgL) 1 to 20 0.12 0.17 0.20 0.10 0.17 0.07 0.05 0.23 0.38Aluminum (mgL) 0.002 0.002 0.002 0.002 0.020 0.020 0.020 0.020 0.020Boron (mgL) 0 to 20 0.0 0.0 0.2 10.9 n/a n/a n/a 0.30 0.30Potassium (mgL) 100 to 500 0.0 0.0 2.6 13.3 0.0 0.0 0.0 22.5 15.0Sodium (mgL) 2,000 to 5,000 24.7 27.8 427.7 51.7 546.5 682.1 646.7 504.3 408.9

TDS (mgL) < 50,000 105 306 1,302 599 1,657 2,014 1,918 5,486 5,769TSS (mgL) < 50 2.5 2.6 5.6 0.3 30.0 16.0 7.5 4.8 0.4

Water Requirements

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Stimulation Treatments and Fluid SystemsStatistical Analysis (Vaca Muerta)•Vert and Hztal wells, zones and well groups•Gas and Wet Gas - Avg water p/stage 2,000m3•Oil - Avg water p/stage 700 to 1,650m3

•Vert well = 5,500m3 and Hztal well = 18,000m3

•Type of treatments: Hybrid (SW-LG-XL or SW-XL)• SW, 45 to 80%• LG, 0 to 30%• XL, 10 to 50% • Some cases 100% SW


Certain particularities•(J) – no use FR but used scale inhibitor, if need to use LG or XL is a 20ppt CMHPG-Zr•(G) – no use clay stabilizer•Mostly XL fluid used, is a 20ppt guar-borate

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Stimulation Treatments and Fluid SystemsStatistical Analysis (Neuqina Basin - Tight)•Vert and Hztal wells, zones and well groups•Lajas or Punta Rosada = 1,600m3 p/Vwell.•Mulichinco = 1,800m3 Vw. and 2,200m3 Hw.

•Type of treatments: • Hybrid (SW-LG-XL or SW-XL)• 100% XL


Subgroup D 1

Year Fracture Type Systems Additional Avg. Vol. (m3)

2007-09 Conventional (XL) CMHPG-zr (25 ppt) 285

2010 Hybrid (LG-XL) guar (10 ppt) - guar-borate (20 ppt) PrePad CO2 (12%) of treatment vol. 375

2011 Hybrid (LG-XL) guar (10 ppt) - guar-borate (20 ppt) 470

2012 Hybrid (SW-LG) SW - guar (20 ppt) 350

2013-14 SW SW 1,100

Subgroup D 2

Year Fracture Type Systems Additional Avg. Vol. (m3)

2003-07 Conventional (XL) HPG-borate (25 ppt) 10% Methanol in base fluid 220

2008-09 Hybrid (LG-XL) CMHPG (10 ppt) - CMHPG-zr (20 ppt) PrePad CO2 (20%) of treatment vol. 425

2010-11 Hybrid (LG-XL) guar (10 ppt) - guar-borate (20 ppt) PrePad CO2 (10%) of treatment vol. 550

2011-14 Hybrid (SW-XL) SW - guar-borate (20 ppt) PrePad CO2 (15%) of treatment vol. 600

Table 2—Summary of various information for two subgroups of D wells, Mulichinco formation.

Mulichinco Evolution (Two Sgroup of wells)

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Water Logistic


Storages Systems• Mobile fracture tanks (80 m3) - B• Circular tanks (1,000 to 5,500 m3) - A• Pits or dams

• small (15,000 m3) - C• large (35,000 m3) - D

Water Handling• Trucks • Piping System (tubing or aluminum pipe) from 300 m

to 1.5 Km - C• Centrifugal pumps (40 to 60 bpm) A-B

Exploratory Wells• Mobile fracture tanks and trucks (Cuyana and GSJ

basins)

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Water Logistic


Tight Gas - GSJ Basin• Recently in the last three years.• Only D-129 formation• Use fresh water , 425 m3 avg p/stage (2 to 3 stages p/wells)• Mobile fracture tanks and use trucks - A

Tight Gas – Neuquina Basin• Activity from 2004 • Lajas, Punta Rosada and Mulichincho formations.• Use fresh water, 300 to 500 m3 avg p/stage • Normally use mobile fracture tanks – B & C• Use trucks to move water• More recently in Mulichinco formation use circular tanks

(Slickwater treatments) - D

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Water Logistic


Multi-Horizontal Well Pad - Vaca Muerta fm (B) • 3 Hztal wells and 33 frac stages• Completion time: 11 days • Water volumen: 60,000m3• Storage capacity: 5,500m3

Primary System (A)• New Water Well #2 (1,000 m3/D) • Storage capacity: 16,000 m3• Distance: 1.5 Km• 8 inch aluminum pipe and centrifugal pumps

Alternative System (C)• Water Well #1 (1,300 m3/D) • Storage capacity: 18,000 m3 (two water storage)• Distance: 800 m to 2.3 Km – (Ww#1 = 4.5 Km)• 8 inch aluminum pipe and centrifugal pumps• 4 ½ inch tubing from Ww#1

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Use and Reuse Non Traditional Waters

Physical-Chemical Analysis - (Flowback & Produced)


Evaluation Non Traditional Water•Tight and Shale Flowback-produced water untreated•Non traditional water, treated

Application for fracture fluid:•Clay swelling and inhibition testing•Evaluation a new crosslinked fluid •Damage by precipitates generated for change in the pH

Area West South South South South South East West West West WestGroup of Wells D D D D A C G H H H HSub-Group D#1a D#2a D#3a D#3b A#1a C#1a G#1a H#7a H#1a H#2a H#3aReservoir Tight Tight Tight Tight Shale Shale Shale Shale Shale Shale ShaleType Water FB FB FB FB PROD FB PROD PROD FB FB FBSpecific gravity 1.042 1.018 1.060 1.060 1.130 1.045 1.065 1.136 1.074 1.123 1.143pH 6.38 6.69 6.00 5.98 5.62 6.35 5.74 6.48 6.74 5.06 5.25Resistiviy (ohms-cm) 0.109 0.176 0.026 0.024 n/a 0.082 0.074 0.026 0.067 0.030 0.023Temperatura (°C) 21.1 21.2 21.6 21.6 n/a 20.8 21.2 20.2 26.0 23.0 24.0

Carbonate (mgL) 0 0 0 0 0 0 0 0 0 0 0Bicarbonate (mgL) 353.9 2,257.7 109.8 85.4 257.3 610.2 195.3 146.4 1,196.0 131.8 107.4Chloride (mgL) 30,011.9 15,005.9 118,546.8 126,049.8 86,837.6 37,014.8 58,022.9 118,546.8 67,026.5 106,041.9 131,051.8Sulfate (mgL) 370.0 420.0 40.0 35.0 0.0 0.0 235.0 0.0 10.0 262.5 137.5Calcium (mgL) 3,206.4 1,402.8 13,306.6 15,711.4 15,967.9 6,012.0 15,230.4 21,643.0 7,134.2 23,406.7 17,955.8Magnesium (mgL) 1,264.6 413.4 1,459.2 1,167.4 4,902.9 1,264.6 729.6 2,140.2 1,702.4 3,988.5 2,723.8Barium (mgL) 0 0 0 0 725 100 0 800 800 0 0Strontium (mgL) 270.0 0.3 948.0 840.0 n/a n/a 702.0 2,078.0 n/a 2,120.0 4,210.0Total Iron (mgL) 118.50 194.00 26.50 21.75 38.00 56.25 21.50 21.25 575.00 243.75 6.50Aluminum (mgL) 0.002 0.002 0.020 0.020 n/a 0.050 0.020 0.020 0.020 0.020 0.020Boron (mgL) 7.8 2.0 10.2 8.4 n/a 7.7 21.3 29.8 24.2 10.4 17.2Potassium (mgL) 535.0 0.0 1,015.0 1,028.8 2,150.5 0.0 750.0 2,750.0 250.0 998.0 2,130.0Sodium (mgL) 13,149.7 8,381.8 57,821.5 60,450.3 27,250.3 14,590.7 18,178.5 45,234.5 32,225.5 34,489.0 59,261.3

TDS (mgL) 49,010 28,076 192,325 204,550 138,129 58,187 93,363 190,562 110,920 171,682 217,584TSS (mgL) 569.2 27.7 84.0 119.0 n/a 666.0 356.5 714.5 163.0 310.4 235.6

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Use and Reuse Non Traditional Waters


Water Type Treated Water

Area West East East West West West

Group of wells H J S H H H

Subgroup T-H#1a T-J#1a T-S#1a T-H#2c T-H#7a T-H#4b

Reservoir Shale Shale Shale Shale Shale Shale

Type water FB FB FB FB PRO FB

Treated method I II II III IV filtered

Specific gravity 1.060 1.094 1.160 1.070 1.125 1.060

pH 7.84 5.87 8.00 7.32 9.12 6.38

Resistivity (ohms-cm) 0.075 0.049 0.028 0.047 n/a 0.046

Temperature (°C) 19.5 21.1 21.9 18.1 n/a 21.8

Carbonate (mgL) 0 0 36 0 66.5 0.0

Bicarbonate (mgL) 219.7 170.9 1,073.9 244.1 0.0 268.5

Chloride (mgL) 59,523.5 85,033.6 121,548.0 61,524.3 104,687.0 67,526.7

Sulfate (mgL) 0.0 325.0 130.0 6,375.0 5.0 80.0

Calcium (mgL) 6,332.6 14,909.8 28,216.3 3,206.4 155.0 16,354.6

Magnesium (mgL) 729.0 1,167.4 155.7 1,945.6 857.0 1,264.6

Barium (mgL) 110 0 0 0 874 0

Strontium (mgL) 1,400.0 1,080.00 7,550.00 177.00 1,846.0 2,960.0

Total iron (mgL) 0.45 11.00 5.50 2.60 1.32 18.25

Aluminum (mgL) 0.020 0.002 0.020 0.002 0.920 0.020

Boron (mgL) 12.0 13.7 1.5 8.2 22.8 63.0

Potassium (mgL) 16.0 1,945.0 4,390.0 253.1 2,066.0 1,497.5

Sodium (mgL) 29,984.4 34,054.7 46,580.6 35,389.8 47,182.0 21,242.7

TDS (mgL) 96,916 137,617 197,746 108,940 172,097 108,251

TSS (mgL) 4.4 34.6 16.0 4.3 10.1 98.0

Table 4—Physical and chemical results for four samples of flowback and produced water.

Physical-Chemical Analysis - (Treated FB-PD Water)

Treatment methods:•I to III, chemical coagulation, flocculation, and separation

•IV, electrocoagulation, pH adjustment, weir tank separation, and multimedia filtration.

•Only filtered .

Treatment effect:•amount reduction of iron and TSS

•pH values ranging from slightly acidic to neutral to slightly alkaline

•sample T-H#4b was only filtered and shown higher values TSS

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Clay InhibitionCapillary suction time (CST) •Clay stabilizers tested and used in Tight and Shale:

• Quaternary ammonium salt - 1.4 gpt• Inorganic salt (KCL) – 1% to 2%• New ultralow-molecular-weight cationic organic

polymer (liquid) – 0.5 to 1.5 gpt


Tight-CST Ratio Tight-XRD

Type Group Wells Subgrup Percentage

(%) TDS

(mg/L) Clay Stabilizer

(gpt) DI — — 100 0 1.4

Produced H H#7a. 100 190,562 No

*Clay stabilizer = quaternary ammonium salt

Table 5—Water evaluated in tight and shale formation .

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Fracturing Fluid (Review new frac fluids)


Recent, studies and development of fracturing fluids using no traditional waters:

•Laboratory Studies - Haghsgenas and Nasr El Din (2014)

•Additional Component Added to Nontraditional Waters to Improve the Performance of Fracture Fluid - Li et al. (2009), Li et al. (2010), Fedorov et al. (2014)

•Nontraditional Waters, Treated - LeBas et al. (2013), Monreal et al. (2014)

•Nontraditional Waters, Not Treated - Huang et al. (2005), Bonapace et al. (2012), Kakadjian et al. (2013), Legemanh et al. (2013), Li et al. (2014)

Bonapace et al (2015), present a new fracture fluid. In this paper was evaluated for two various conditions for tight reservoir and using 100% of flowback water only filtered.

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Fracturing Fluid (Tight Gas application)


Intermediate depth wells:•Formation - Mulichinco.•Depth - 1550 to 1800 m.•Type of fracture treatment - Hybrid, correspond to Well Group D and H, located at the western zone (Fig. 3A).•BHT average of 150°F.•Slurry fracture rate average of 40 to 60 bbl/min.•Pumping time average of 45 to 65 minutes.

Test No. Water TDS (mg/L) Type Test BHT

(°F) Gel Load

(ppt) 1 South Zone—D#3a filtered 192,325 Stabilitiy 150 25

2 South Zone—D#3a filtered 192,325 Stabilitiy 150 30

3 South Zone—D#3a filtered 192,325 Break 150 25

4 West Zone—T-H#4b 108,250 Stabilitiy 220 25


6 West Zone—T-H#4b 108,250 Break 220 30

*For more details about water, refer to Tables 3, 4, and 6. Sample D#3a was filtered in the laboratory.

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Fracturing Fluid (Tight Gas application)


Deeper wells: •Formation - Lajas and Punta Rosada.•Depth - 3400 to 3900 m.•Type of fracture treatment - 100% XL fluid, correspond to Well Group D, located at southern zone (Fig. 3A).•BHT average was 220°F.•Slurry fracture rate average was 20 to 35 bbl/min.•Pumping time average was 30 to 50 minutes

Test No. Water TDS (mg/L) Type Test BHT

(°F) Gel Load

(ppt) 1 South Zone—D#3a filtered 192,325 Stabilitiy 150 25

2 South Zone—D#3a filtered 192,325 Stabilitiy 150 30

3 South Zone—D#3a filtered 192,325 Break 150 25



6 West Zone—T-H#4b 108,250 Break 220 30

*For more details about water, refer to Tables 3, 4, and 6. Sample D#3a was filtered in the laboratory.

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Fracturing Fluid (Damage by precipitates - pH)


Sample Water Type Subgroup Wells TDS

(mg/L) Ca

(mg/L) Mg

(mg/L) TSS

(mg/L) Filtered TSS

(mg/L) A - FB D#2a 28,076 1,402 413 27.7 18.2

B - FB D#3a 192,325 13,306 1,459 84.0 36.7

C - FB H#4a 212,982 30,781 4,669 240.0 25.6 Table 6—Water evaluated for damage in sandpack.

• Most type of treatment are Hybrid jobs (shale) and Hybrid, XL or SW (tight)

• Average volume of water per well,are • Tight - Vertical 1,600m3 and Horizontal 2,200m3• Shale - Vertical 5,500m3 and Horizontal 18,000m3

• More common water storage systems are mobile fracture tanks and circular tanks. Mainly water transfer systems are, trucks and pipeline systems

• Flowback and produced water have high levels of TDS, TSS, Ca, Mg, Fe and B. Treatment methods used reduce TSS and Fe

• Non traditional water• No need not use clay stabilizer• Need to be filtered (high content of TSS can impact negatively in proppant pack)• High pH fracture fluid produce floculant or insoluble components (negative impact)

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Conclusions


• A new fracture fluid can be formulated using blend of water or 100% non traditional water treated or only filtered, have very good proppant transport capacity and less residue than traditional guar-borate fluid currently used

• Water reuse is a key factor for sustainable shale developments.

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Conclusions…cont


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AcknowledgementsThe author thanks Halliburton for the permission to publish this paper.

Special thanks are extended to the Argentina Unconventional Reservoir Solution Team for support and to Evangelina Borra, Maximiliano Coronel and Dario Tello for their unconditional work and support in the laboratoy.

Aerial pictures are courtesy of Gonzalo Arribere (HYDROFRAC, an El Fortin Constructions division).

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Thanks you for your attention

Engineering

SPE-174119