Well Completion Report: OzEpsilon-1, Study notes of Building Materials and Systems

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OzEpsilon-

South Georgina Basin

Northern Territory, Australia

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Valid from Rev. no.

Enclosures to OzEpsilon-1 Basic Well Completion Report (DVD)

OzEpsilon-1 Core images, white and UV light

Mudlog and gas recordings (pdf and LAS) Openhole Wireline logs (pdf and LAS)

• OzEpsilon-
• 1 General Data Table of contents
• 1.1 Well Objective
• 1.2 Well Outcome
• 1.3 Well Summary Table.......................................................................................................................................
• 2 Drilling..........................................................................................................................................................
• 2.1 Drilling Summary...........................................................................................................................................
• 2.1.1 Non-productive time summary
• 2.1.2 Time versus Depth Curve
• 2.2 Casings
• 2.3 Well Path - Directional Data
• 2.4 BHA Records
• 2.5 Cementing Summary
• 2.6 Bit Records
• 2.7 Drilling Fluids
• 2.8 Permanent Plug and Abandonment
• 2.8.1 Plugging
• 3 Well Evaluation Logs
• 4 Cores, Cuttings and samples
• 4.1 Coring, cores and samples
• 4.2 Cuttings
• 5 Pore Pressures and Temperature
• 5.1 Pore pressure and stress
• 5.2 Formation temperature
• App A Directional Data – surveys
• App B Well Schematics..........................................................................................................................................
• App C Wellhead (Used for the drilling phase and removed after P&A performed)
• App D Well Barriers
• App E Pore Pressure and Fracture Gradient Plot
• App F Core Intervals and Preserved Samples
• App G Cuttings and Core Descriptions

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1 General Data

1.1 Well Objective

The OzEpsilon-1 vertical exploration well was one of five 2014 Statoil wells drilled to de-risk the unconventional play in

the Middle Cambrian carbonate deposits; the Arthur Creek Hot Shale and the Thorntonia Limestone (dolomitized) in the

South Georgina Basin. The OzEpsilon-1 well was located in the northern part of EP 128. Permeabilities in these

formations are expected to be too low for conventional production methods and the most prospective wells are planned to

be stimulated through hydraulic fracturing. OzEpsilon-1 was drilled as a stratigraphic well and was not planned to be

stimulated and production tested.

The well was located at a tectonically undisturbed location to best assess the presence of hydrocarbons. Extensive

coring and wireline logging were performed to better understand the rock properties and perform a hydrocarbon potential

evaluation.

The drilling objective for the OzEpsilon-1 well included two hole sections. The upper section (12 ¼” hole and 9 5/8”

surface casing) was designed to be cased and cemented to surface to:

• isolate the aquifers,
• achieve kick tolerance,
• ensure well integrity towards underlying potential hydrocarbon bearing zones.

The lower 7 7/8” drilling section included continuous coring, focusing on the basal Arthur Creek Hot Shale and into the

underlying Thorntonia Limestone.

The final objective of the drilling phase was to permanently plug and abandon the OzEpsilon-1 well according to the

requirements of the NT Department of Mines and Energy.

1.2 Well Outcome

The conductor was preset at 18.5m MD and 12 ¼” surface hole was drilled to 321.5m MD RKB. 9 5/8” surface casing

was run to 319m MD RKB and cemented to surface, isolating the aquifers. Kick tolerance and well integrity were

confirmed with a formation integrity test of 13.3 ppg EMW at 325m MD RKB.

7 7 / 8 ” production hole was then drilled to coring point at 557m MD RKB. 3 1 / 2 ” wireline retrieved coring was conducted using

18m core barrels. Good recovery was achieved through the lower Arthur Creek Formation and the Arthur Creek Hot

Shale. On intersecting the Thorntonia Limestone, core recovery became poor. Broken core packed off the core barrel,

resulting in only 0.6m to 1.4m of core recovered per run. Coring was terminated at 607.4m in the Thorntonia Limestone

and conventional drilling was resumed. The well was terminated in granite basement at 665m MD RKB.

Formation tops were encountered within the uncertainties of the prognosed depths. Red Heart Dolomite was penetrated

instead of the prognosed Sun Hill Arkose.

Wireline logging was conducted, and numerous core analyses performed.

OzEpsilon-1 was planned as a stratigraphic exploration well and so the well was permanently plugged and abandoned

with the drilling rig immediately after the openhole wireline logging (production casing was not run).

Basic Well Completion ReportOzEpsilon-

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Page 10 of 35

Figure 1

Map of the Statoil licences area and position of the OzEpsilon-1 well location in EP

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Figure 2 Survey certificate

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A time overview for the OzEpsilon-1 activities can be seen in Table 2-1.

Table 2-1 Summary of operations for OzEpsilon-

Section Start time End time Rig name

AU OZEPSILON-1 Move-In, Rig Up 29.Jun.2014 02:00 02.Jul.2014 07:00 EDA 2 AU OZEPSILON-1 Drilling, Surface 02.Jul.2014 07:00 04.Jul.2014 23:30 EDA 2 AU OZEPSILON-1 Casing, Surface 04.Jul.2014 23:30 06.Jul.2014 10:30 EDA 2 AU OZEPSILON-1 Drilling, Production 06.Jul.2014 10:30 09.Jul.2014 12:45 EDA 2 AU OZEPSILON-1 Formation evaluation, Production 09.Jul.2014 12:45 09.Jul.2014 22:00 EDA 2 AU OZEPSILON-1 Permanent P&A (DP) w/ RIG 09.Jul.2014 22:00 10.Jul.2014 21:00 EDA 2 AU OZEPSILON-1 Rig Down 10.Jul.2014 21:00 11.Jul.2014 09:00 EDA 2

2.1.1 Non-productive time summary

Table 2-2 Summary of the non-productive time for OzEpsilon-

Well Date Incident Category Company Hours

OzEpsilon-1 02.Jul.2014 RIG-06 Lost circulation Drilling Surface Statoil 33. OzEpsilon-1 10.Jul.2014 CEM-08 Cementer support Permanent P&A (DP) w/ RIG Halliburton 5. Total hours : 38.

2.1.2 Time versus Depth Curve

The time versus depth illustration with explanatory remarks can be seen in Figure 3 on the next page.

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Figure 3 Time versus depth curve for OzEpsilon-

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BHA NO: 2

RUN TYPE: Drilling run

DESCRIPTION: 7 7/8" Production BHA

RUN NAME: 2

String component OD in ID in

Length

m Acc length m

BIT 7.875 2.250 0.26 0.

MUD MOTOR 6.750 1.500 8.15 8.

FLOAT SUB 2.250 0.69 9.

X-OVER 6.620 2.250 0.81 9.

STABILIZER 7.750 2.870 1.86 11.

X-OVER 6.500 2.250 0.88 12.

DRILL COLLAR 6.250 2.250 101.58 114.

JAR 6.250 2.250 9.36 123.

X-OVER 6.250 2.500 0.30 123.

BHA NO: 3

RUN TYPE: Coring run

DESCRIPTION: 7 7/8" Coring BHA

RUN NAME: 1

String component OD in ID in

Length

m Acc length m

BIT 7.875 3.500 0.47 0.

CORE BARREL 4.600 8.23 8.

STABILIZER 4.600 0.90 9.

CORE BARREL 4.600 8.24 17.

STABILIZER 4.600 0.91 18.

COREBARREL 4.600 0.73 19.

COREBARREL 4.600 0.72 20.

DRILL COLLAR 4.600 94.08 114.

BHA NO: 4

RUN TYPE: Drilling run

DESCRIPTION: 7 7/8" Production BHA

RUN NAME: 3

String component OD in ID in Length

m

Acc length m

BIT 7.875 0.24 0.

MUD MOTOR 6.750 1.500 8.15 8.

FLOAT SUB 6.625 2.250 0.69 9.

DRILL COLLAR 6.250 2.250 9.28 18.

DRILL COLLAR 6.250 2.250 9.30 27.

X-OVER 6.500 2.188 0.81 28.

STABILIZER 7.750 2.870 1.86 30.

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String component OD in ID in

Length

m

Acc length m

X-OVER 6.500 2.250 0.88 31.

DRILL COLLAR 6.250 2.250 83.22 114.

JAR 6.500 2.250 9.08 123.

DRILL COLLAR 6.250 2.250 9.11 132.

X-OVER 6.500 2.375 0.59 133.

HW DRILL PIPE 6.500 3.000 55.90 189.

X-OVER 2.250 1.21 190.

X-OVER 2.250 0.60 190.

2.5 Cementing Summary

Cementing of the 9 5/8" surface casing :

Operation summary: Pumped 1 bbl freshwater spacer, 10bbl Flochek, 10bbl freshwater spacer, 134bbl 13.5ppg Halcem,

135bbl Class G (in attempt to get cement to surface), 80bbl freshwater dispacement. No returns throughout job. Top up

job required to circulate cement to surface.

Table 2-4 Cementing summary for OzEpsilon-1 Surface casing

Fluids pumped Type Densityppg Volumebbl Pump Rategal/min

Pump

Press

psi

Return

Preflush Econolite 9.30 10.0 6 15 N Spacer before Fresh Water 8.33 10.0 6 15 N Spacer before #2 Fresh Water 8.33 10.0 6 15 N Lead Halcem 13.50 134.0 6 200 N Tail Class G 13.50 135.0 6 250 N Displacement Fresh Water 8.33 80.0 2 110 N

2.6 Bit Records

OzEpsilon-1 bit records can be seen in the tables below.

Tables 2-5 Bit records for OzEpsilon-1 bit runs

Run

no

Bit size Bit

no

BHA

no

Bit type IADC

code

Bit manufacturer

1 12 1/4" 1 1 MM66 Halliburton 2 7 7/8" 2 2 DSH616M NOV 3 7 7/8" 3 3 DC613QL Corpro 4 7 7/8" 4 4 EQH44D2R Halliburton

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2.7 Drilling Fluids

The OzEpsilon-1 well was drilled with water based mud. The water to fill the turkeys nest was supplied from the Epsilon

water bore drilled on the OzEpsilon-1 well site.

The mud used to drill the surface hole was a Gel Spud mud changing to water at 50m and a Gel/Polymer mud from 322m

to total depth. While drilling the 12 1/4” hole section the main problem encountered was related to downhole losses which

reached 3661bbl for this interval. Initially 100bbl of LCM was mixed based on 15ppb Gel and 5ppb Frackseal Fine; 5ppb

Sandseal Fine; 2ppb Cellplug and 8ppb Mica Coarse. Finally the maximum LCM concentration was increased to 32ppb in

the second 100bbl pill. Although 4 cement plugs were pumped, the losses continued until the end of the section and 9

5/8” casing was cemented and an additional top up cement job was performed.

The 7 7/8” hole was drilled without fluid losses to the formation.

A short summary of the mud properties is given in the table below:

Table 2-6 Drilling fluids summary

Hole Section Fluid Type Mud Weight (ppg)

Viscosity (sec/qt)

PV

(cp)

YP

(lb/100 ft 2 )

Fluid Loss (bbl/hr) pH

Surface Spud Mud 8.4 26-29 1 4 150-300 8. Production Polymer Mud 8.5-8.8 33-36 5-7 9-13 0 9-9.

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2.8 Permanent Plug and Abandonment

A 5 hour downtime was recorded because there was not enough cement on the location for the permanent plug and

abandonment operations and a new cement bulker had to be summoned.

The lower cement plug was placed in the open hole from 665m to 418m.

Plug number 2 was placed from tagged 424m to inside the 9 5/8” casing at 173m.

Plug number 3 was mixed and pumped to cover the interval 181m to surface.

5.2bbl of cement was observed on surface.

2.8.1 Plugging

Table 2-7 Permanent plug and abandonment cement plugs

Plug top MD Plug bottom MD Company Plug No. Plug type Job objective 418 655 Halliburton 1 Open hole Permanent P&A Measured plug top MD Measured by Hole size Casing size Placement method 7 7/8” Mixed and pumped plug #1 - 50.2bbl of 13.5ppg cement slurry, 5bbl/min. TOC 418m MD. Fluids pumped Type Density ppg Volume bbl Pump rate l/min Pump pressure psi Slurry Class G cement 13.5 50 5.0 200

Plug top MD Plug bottom MD Company Plug No. Plug type Job objective 173 424 Halliburton 3 Open hole into casing Permanent P&A Measured plug top MD Measured by^ Hole size^ Casing size^ Placement method 7 7/8” 9 5/8” Remarks: Mixed and pumped plug #2 - 57.7bbl of 13.5ppg cement slurry, 5.2bbl/min. TOC 173m MD. Fluids pumped Type^ Density ppg^ Volume bbl^

Pump rate l/min Pump pressure psi Slurry Class G cement 13.5 58 5.0 200

Plug top MD Plug bottom MD Company Plug No. Plug type Job objective 0 181 Halliburton 3 Casing Permanent P&A Measured plug top MD Measured by Hole size Casing size Placement method 9 5/8” Remarks: Mixed and pumped plug #3 - 46bbl of 13.5ppg cement slurry, 5.1bbl/min. 5.2bbl cement to surface. Fluids pumped Type Density ppg Volume bbl Pump rate l/min Pump pressure psi Slurry Class G cement 13.5 46 5.1 300