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Home My WebLink About2013 Oooguruk Unit Annual Reservoir Surveillance Report Oooguruk-Kuparuk Oil Pool Oooguruk Field April 15, 2013 Table of Contents SUBJECT PAGE 1.0 Progress of the Enhanced Recovery Project .............................................................................. 1 2.0 Results and Analysis of Reservoir Pressure Surveys Within the Pool .................................. 1 3.0 Results and Analysis of Production and Injection Log Surveys, Tracer Surveys, Observation Well Surveys and Any Other Special Monitoring ............................................. 1 4.0 Review of Pool Production Allocation Factors and Issues Over the Year ............................ 1 5.0 Reservoir Management Summary .............................................................................................. 2 Attachments A. Voidage Balance by Month of Produced Fluid and Injected Fluids 2012 B. Map of Kuparuk Well Locations C. Form 10-412 Pressure Report for Kuparuk D. Kuparuk Reservoir Pressure Map – August 2012 Annual Reservoir Surveillance Report Pioneer Natural Resources Alaska, Inc. Oooguruk-Kuparuk Oil Pool Oooguruk Development Project Page 1 of 7 1.0 Progress of the Enhanced Recovery Project During 2012, there were no new drilling activities within the Kuparuk Pool. There are currently five active wells (three producers and two injectors) and three inactive wells. The inactive ODSK-13 within the Ivik fault block is shut-in pending rig a rig workover. The ODSN-40 within the Colville Delta fault block is shut-in due to inconsistent injection. The ODSK-42Ai is shut-in after short period of injection since it could not maintain consistent injection at the water injection header pressure post gel treatment in 2010. The ODSK-14, ODSK-33 and ODSK-41 wells continued to produce throughout 2012. Water breakthrough occurred in ODSK-35i prior to conversion to injection. The ODSK-38i well continued on injection throughout the year and ODSK-35i had first full year of injection. Both injectors are performing as expected in replacing off take as of December 2012. The locations of these wells are shown on Attachment B. Average daily Kuparuk production for 2012 was 2,070 BOPD. Cumulative oil production from the Oooguruk-Kuparuk Oil Pool during 2012 was 755 MBO and 7,674 MBO since field start-up. No additional drilling for the pool is planned for 2013. Average daily Kuparuk water injection for 2012 was 9,620 BWPD. Cumulative water injection in the Oooguruk-Kuparuk Oil Pool during 2012 was 3,511 MBW and 11,677 MBW since the start of the project. 2.0 Results and Analysis of Reservoir Pressure Surveys within the Pool Pressure build up tests were completed in ODSK-35i, ODSK-38i and ODSK-42Ai during 2012, the results of which are presented in Attachment C. The pressure in ODSK-42Ai indicates pressure drawdown in this area of the reservoir as the well has been shut in from injection since the gel squeeze to shut off thief zones. 3.0 Results and Analysis of Production and Injection Log Surveys, Tracer Surveys, Observation Well Surveys and any Other Special Monitoring A chemical tracer program was initiated in May 2012. Tracers were injected into ODSK-35i and ODSK-38i. By year end, 2012 tracer concentrations have been observed in ODSK-33 from ODSK-35i. No other tracers have been observed in producers. Surveillance will continue into 2013. 4.0 Review of Pool Production Allocation Factors and Issues Over the Year Production from the Oooguruk-Nuiqsut, Oooguruk-Kuparuk and Oooguruk-Torok pools is commingled at the surface into a common production line. Allocation between the pools is based on ratio of total production for a pool to the total production for the Oooguruk Unit. The pool allocation factors for 2012 are: Page 2 of 7 Oooguruk-Nuiqsut Pool: 62.1% Oooguruk-Kuparuk Pool: 30.1% Oooguruk-Torok Pool: 7.8% Theoretical production for individual wells for both pools is calculated on a daily basis. During 2012 wells were produced with chokes at 100% the most of the time due to the capacity of the production line. Daily theoretical production for a well was calculated using the data from the most current well test and the amount of time a well was on production for a given day: oductionlDailyTheoreticaBOPDxDailyRate dayMinutes Minutes Welltest produced Pr)(1440 = The daily allocation factor for the unit is calculated by dividing the actual total production for the day by the sum of the theoretical daily production for each individual well. Daily allocated production is assigned to each well by multiplying its theoretical daily production by the daily allocation factor. The average daily allocation factor for 2012 was 0.98. 5.0 Reservoir Management Summary The Alaska Oil and Gas Conservation Commission (AOGCC) issued pool rules under Conservation Orders No. 645, 596 and 597 for the Oooguruk-Torok, Oooguruk-Kuparuk and Oooguruk-Nuiqsut reservoirs, respectively. While there is no subsurface commingling, unitized substances produced from the Oooguruk-Torok, Oooguruk-Nuiqsut and the Oooguruk-Kuparuk oil pools are commingled on the surface. Area injection orders authorizing the injection of fluids for enhanced oil recovery in the Oooguruk-Kuparuk and Oooguruk-Nuiqsut reservoirs were issued by the AOGCC as Area Injection Orders No. 33 and 34, respectively. Pioneer commenced injection into both reservoirs in 2009. Kuparuk production has exceeded expectations from ODSK-33, ODSK-41 and ODSK-14 due to possible non-matrix flow into these wells. Kuparuk injection commenced in 2009, into ODSK- 38i with excellent injection rates. Kuparuk injection commenced in 2011 into ODSK-35i and ODSN-40 (converted from Nuiqsut completion to Kuparuk completion). Injection rate into ODSK-35i is very good, with rate into ODSN-40 good, considering the pay thickness at that location. The better than expected water injection rate has arrested the gas/oil ratio (GOR) increase in the ODSK-33 and has stabilized the flowing bottomhole pressure. The ODSK-33 experienced water breakthrough in August 2010. This was approximately the timing that reservoir simulation had suggested for breakthrough. The water cut increased relatively rapidly and reached approximately 91% by the end of, 2012. ODSK-41 is much further away from injection and has not yet seen a dramatic response to water injection in ODSK-38i. Injection logging confirmed that water injection in the K-38i well was limited to the perforated Kuparuk section. Injection was initiated in ODSK-42Ai in January 2010. Unfortunately, this resulted in a very early water breakthrough event in the ODSK-41 well. The ODSK-42Ai was shut in and the water injection rate quickly decreased from the producing well. It is possible a fracture system Page 3 of 7 connects the two wells together. This was not unexpected based on the high productivity from the ODSK-41 wells originally. In 2010, ODSK-42i was squeezed with a combination of gels to attempt to seal up the fracture connection. Those are polyacrylamide gels that set up to a “ringing gel” at reservoir conditions. The ODSK -42Ai was placed back on injection and was injecting just under 1,000 BWPD for about 30 days. Then, after an upset event from the Kuparuk River Unit Seawater Treatment Plant, continuous injection could not be sustained. Some solid materials may have caused some near wellbore plugging. ODSK-42Ai is currently shut-in. ODSK-35 and ODSK-14 were both drilled during 2010. The total thickness of the Kuparuk was less than expected in these wells to the north and northwest of the ODSK-33. The wells had very high initial productivity from good reservoir quality, but have declined due to the thinner nature of the reservoir. ODSK-35i was converted to injection in late, 2011. With ODSK-35i and ODSK-38i both injecting, reservoir voidage replacement is maintained, pressure in the reservoir is increasing, and GORs are decreasing. ODSK-13 was drilled in late 2011 as horizontal producer completed to test the thickness and productivity of the Ivik fault block. It is awaiting a rig work-over. ODSN-40, a Nuiqsut horizontal completion, had rig workover in 2011 to convert to dedicated Kuparuk injection. This well was completed and injected into the Kuparuk formation within the Colville-Delta fault block in 2012 an attempt to aid with pressure support and oil recovery into the ODSK-33 producer within the Kalubik fault block. It is shut-in due to low injectivity. Page 4 of 7 ATTACHMENT A Voidage Balance by Month of Produced Fluids and Injected Fluids 2012 Page 5 of 7 ATTACHMENT B Map of Kuparuk Well Locations Page 6 of 7 ATTACHMENT C Form 10-412 Pressure Report for Kuparuk 6. Oil Gravity: 25 8. Well Name and Number: 9. API Number 50XXXXXXXXXXXX NO DASHES 10. Type See Instructions 11. AOGCC Pool Code 12. Zone 13. Perforated Intervals Top - Bottom TVDSS 14. Final Test Date 15. Shut-In Time, Hours 16. Press. Surv. Type (see instructions for codes) 17. B.H. Temp. 18. Depth Tool TVDSS 19. Final Observed Pressure at Tool Depth 20. Datum TVDSS (input) 21. Pressure Gradient, psi/ft. 22. Pressure at Datum (cal) ODSK-35 50703205600100 WI 576100 Kuparuk 6085 - 6126 8/5/10 209 PBU 161 5849 3643 6050 0.44 3,731 ODSK-38 50703205840000 WI 576100 Kuparuk 6013 - 6041 8/5/10 209 PBU 120 5840 3132 6050 0.44 3,224 ODSK-42 5070206050100 WI 576100 Kuparuk 5735 - 5746 9/9/10 209 PBU 144 5681 2500 6050 0.44 2,662 *Recorded reservoir pressure prior to flowing back well Printed Name Date 23. All tests reported herein were made in accordance with the applicable rules, regulations and instructions of the Alaska Oil and Gas Conservation Commission. I hereby certify that the foregoing is true and correct to the best of my knowledge. Signature Title 3. Unit or Lease Name:4. Field and Pool:5. Datum Reference:7. Gas Gravity: Oooguruk Oooguruk-Kuparuk 6050 0.7 STATE OF ALASKA ALASKA OIL AND GAS CONSERVATION COMMISSION RESERVOIR PRESSURE REPORT 1. Operator:2. Address: Pioneer Natural Resources Alaska 700 G Street, Suite 600, Anchorage, AK 99501 Page 7 of 7 ATTACHMENT D Kuparuk Reservoir Pressure Map – August 2012 Annual Reservoir Surveillance Report Oooguruk-Nuiqsut Oil Pool Oooguruk Field April 15, 2013 Page 1 of 8 Table of Contents SUBJECT PAGE 1.0 Progress of the Enhanced Recovery Project ...............................................................................1 2.0 Results and Analysis of Reservoir Pressure Surveys Within the Pool ...................................1 3.0 Results and Analysis of Production and Injection Log Surveys, Tracer Surveys, Observation Well Surveys and Any Other Special Monitoring ..............................................2 4.0 Review of Pool Production Allocation Factors and Issues Over the Year ............................2 5.0 Reservoir Management Summary ..............................................................................................2 Attachments A. Voidage Balance by Month of Produced Fluid and Injected Fluids 2012 B. Map of Nuiqsut Well Locations C. Form 10-412 Pressure Report for Nuiqsut D. Nuiqsut Reservoir Pressure Maps – August 2012 Page 2 of 8 1.0 Progress of the Enhanced Recovery Project During 2012, the ODSN-271 injection well was drilled and pre-produced. The producing ODSN-01 was drilled, fracture stimulated and placed on production. The ODSN-25 and ODSN-29 were drilled and completed and are waiting on fracture stimulation treatment as of year-end. The ODSN-23i and ODSN-26i were converted to water injection after a period of pre-production. Within the Kalubik fault block, ODSN-31, ODSN-37 and ODSN-36 continued to produce and ODSN-01 was put on production during 2012. They are supported by water and gas injection in ODSN-32i, ODSN-34i, and ODSN-26i. Within the Colville Delta fault block, ODSN-16, ODSN-17, ODSN-18 continued to produce throughout 2012. They are supported by water and gas injection in ODSN-23i and ODSN-15i. As part of planned under-saturated water-alternating-gas (USWAG) process, gas injection has continued in ODSN-15i throughout most of the year. Within the Ivik fault block, ODSN-27i pre-production was initiated. The ODSN-29 producer is waiting on fracture stimulation as of year-end. No injection has begun in this fault block. The locations of all Nuiqsut wells are shown on Attachment B. Average daily Nuiqsut production during 2012 was 4,322 BOPD. Cumulative oil production from the Oooguruk-Nuiqsut Oil Pool during 2012 was 1,577 MBO and is 4,137 MBO since field start-up. During 2012, water and gas injection continued in the Oooguruk-Nuiqsut oil pool. Offset producing wells have seen gas/oil ration (GOR) stabilization and arrest of production decline. Average daily Nuiqsut injection during 2012 was 4,167 BWPD and 2,722 Mscfd. Cumulative water injection in the Oooguruk-Nuiqsut Oil Pool during 2012 was 1521 MBW and 3,037 MBW since the start of the project. Cumulative gas injection in the Oooguruk-Nuiqsut Oil Pool during 2012 was 993 MMscf and 2,095 MMscf since the start of the project. 2.0 Results and Analysis of Reservoir Pressure Surveys Within the Pool An initial static pressure test was completed on the three new Nuiqsut wells, ODSN-01, ODSN-25 and ODSN-27i, in 2012. The details of the pressure tests are on Attachment C. Page 3 of 8 3.0 Results and Analysis of Production and Injection Log Surveys, Tracer Surveys, Observation Well Surveys and any Other Special Monitoring In ODSN-01 Nuiqsut well surveillance equipment was placed in the production liner to assess oil and water production conformance along the lateral via target fluid tracers which were monitored and analyzed by collecting surface fluid samples over time. Initial data indicate adequate tracer concentrations are being returned in the produced fluids. A quantitative analysis is in progress. 4.0 Review of Pool Production Allocation Factors and Issues Over the Year Production from the Oooguruk-Nuiqsut, Oooguruk-Kuparuk and Oooguruk-Torok pools is commingled at the surface into a common production line. Allocation between the pools is based on ratio of total production for a pool to the total production for the Oooguruk Unit. The pool allocation factors for 2012 are: Oooguruk-Nuiqsut Pool: 62.1% Oooguruk-Kuparuk Pool: 30.1% Oooguruk-Torok Pool: 7.8% Theoretical production for individual wells for both pools is calculated on a daily basis. During 2012 wells were produced with chokes at 100% the vast majority of the time due to the capacity of the production line. Daily theoretical production for a well was calculated using the data from the most current well test and the amount of time a well was on production for a given day: oductionlDailyTheoreticaBOPDxDailyRate dayMinutes Minutes Welltest produced Pr)(1440  The daily allocation factor for the unit is calculated by dividing the actual total production for the day by the sum of the theoretical daily production for each individual well. Daily allocated production is assigned to each well by multiplying its theoretical daily production by the daily allocation factor. The average daily allocation factor for 2012 was 0.98. 5.0 Reservoir Management Summary The Alaska Oil and Gas Conservation Commission (AOGCC) issued pool rules under Conservation Orders No. 645, 596 and 597 for the Oooguruk-Torok, Oooguruk-Kuparuk and Oooguruk-Nuiqsut reservoirs, respectively. While there is no subsurface commingling, unitized substances produced from the three oil pools are commingled on the surface. Page 4 of 8 Area injection orders authorizing the injection of fluids for enhanced oil recovery in the Oooguruk-Kuparuk and Oooguruk-Nuiqsut reservoirs were issued by the AOGCC as Area Injection Orders No. 33 and 34, respectively. Pioneer commenced injection into both reservoirs in 2009. As of January 2013 there are 10 producers and five injection wells, one of which is currently pre-producing in the Oooguruk-Nuiqsut oil pool. Eight of those are active production wells and five are active injection wells. The ODSN-23i and ODSN-26i was converted to injection in 2012. As of year-end 2012, two of the three active fault blocks have injection operations. The focus in 2013 will be to commence injection into the third fault block and to maintain voidage replacement in all three fault blocks. Page 5 of 8 ATTACHMENT A Voidage Balance by Month of Produced Fluids and Injected Fluids 2012 Page 6 of 8 ATTACHMENT B Map of Nuiqsut Well Locations Page 7 of 8 ATTACHMENT C Form 10-412 Pressure Report for Nuiqsut 6. Oil Gravity: 20 8. Well Name and Number: 9. API Number 50XXXXXXXXXXXX NO DASHES 10. Type See Instructions 11. AOGCC Pool Code 12. Zone 13. Perforated Intervals Top - Bottom TVDSS 14. Final Test Date 15. Shut-In Time, Hours 16. Press. Surv. Type (see instructions for codes) 17. B.H. Temp. 18. Depth Tool TVDSS 19. Final Observed Pressure at Tool Depth 20. Datum TVDSS (input) 21. Pressure Gradient, psi/ft. 22. Pressure at Datum (cal) ODSN-01 50703206480000 O 576150 Nuiqsut 6134-6217 4/03/12 INITIAL SBHP 161 6031 3050 6350 0.53 3,219 ODSN-27 50703206550000 O 576150 Nuiqsut 6375-6237 8/15/2012 INITIAL SBHP 153 5875.56 3044.4 6350 0.52 3,291 ODSN-25 50703206560000 O 576150 Nuiqsut 6080-6039 11/8/2012 INITIAL SBHP 151 5,726 2832 6350 0.52 3,156 3. Unit or Lease Name:4. Field and Pool:5. Datum Reference: 23. All tests reported herein were made in accordance with the applicable rules, regulations and instructions of the Alaska Oil and Gas Conservation Commission. I hereby certify that the foregoing is true and correct to the best of my knowledge. Signature 7. Gas Gravity: Oooguruk Oooguruk-Nuiqsut Printed Name Title Date 6350 0.7 STATE OF ALASKA ALASKA OIL AND GAS CONSERVATION COMMISSION RESERVOIR PRESSURE REPORT 1. Operator:2. Address: Pioneer Natural Resources Alaska 700 G Street, Suite 600, Anchorage, AK 99501 Page 8 of 8 ATTACHMENT D Nuiqsut Reservoir Pressure Map – August 2012 Annual Reservoir Surveillance Report Oooguruk-Torok Oil Pool Oooguruk Field April 15, 2013 Table of Contents SUBJECT PAGE 1.0 Progress of the Enhanced Recovery Project .............................................................................. 1 2.0 Results and Analysis of Reservoir Pressure Surveys Within the Pool .................................. 1 3.0 Results and Analysis of Production and Injection Log Surveys, Tracer Surveys, Observation Well Surveys and Any Other Special Monitoring ............................................. 2 4.0 Review of Pool Production Allocation Factors and Issues Over the Year ............................ 2 5.0 Reservoir Management Summary .............................................................................................. 3 Attachments A. Voidage Balance by Month of Produced and Injected Fluids 2012 B. Map of Torok Well Locations C. Form 10-412 Pressure Report for Torok D. Torok Reservoir Pressure Map – August 2012 E. ODST-46 Pressure Monitoring and Daily Injection Volumes (AIO 37, Rule 9) Annual Reservoir Surveillance Report Pioneer Natural Resources Alaska, Inc. Oooguruk-Torok Oil Pool Oooguruk Development Project Page 1 of 6 1.0 Progress of the Enhanced Recovery Project During 2012 Oooguruk-Torok Oil Pool (OTOP) development progressed as planned. The Alaska Oil and Gas Conservation Commission (AOGCC) issued Area Injection Order 37 (AIO 37) authorizing injection of fluids into the OTOP for the purposes of pressure maintenance and enhanced oil recovery. Injection operations were initiated on December 5, 2012 in ODST-46. Production continues from horizontal fracture stimulated producers ODST-45A and ODST-39. A workover was completed on ODST-45A in October to replace a failed ESP. A fourth Oooguruk Drill Site (ODS) development well, ODST-47, was drilled and completed in 2012 and is awaiting hydraulic fracture stimulation during the 2013 winter ice season. Appraisal drilling, logging and testing were conducted in the Sikumi 1 and Nuna 1 wells during 2012. The Nuna 1 well, which was drilled from the planned onshore drillsite location, included a pilot hole and a horizontal well which was completed, fracture stimulated and tested in the 2012 winter season. Log data was acquired in the Sikumi 1 well across the Torok interval. The locations of the existing OTOP wells are shown on Attachment B. Seawater injection was initiated in ODST-46 and monitored pursuant to the rules of AIO 37. Specifically, the well demonstrated mechanical integrity and pressures, injection and annuli, are monitored continuously. During the period of injection, well head injection pressures averaged 1,422 psi, far below the maximum pressure of 2,800 psi, and water rates averaged 2,709 bpd. The early performance data indicates good injectivity and confinement to the OTOP. Attachment E, in compliance with AIO 37, Rule 9, characterizes the well injection for this period. Excluding confidential Nuna 1 test production average daily Torok production for 2012 was 537 BOPD. Cumulative oil production from the OTOP during 2012 was 196 MBO and is 501 MBO since field start-up thru 2012. Average daily Torok water injection for 2012 was 202 BWPD. Cumulative water injection in the OTOP during 2012 was 73 MBW and 73 MBW since the start of the project. Attachment A details the 2012 monthly voidage for the OTOP. 2.0 Results and Analysis of Reservoir Pressure Surveys within the Pool Pressure surveys were conducted in four OTOP wells during 2012. The initial pressures measured in wells ODST-39 and Nuna 1 measured 2,210 psi and 2,259 psi (-5,000 TVDSS datum), respectively. These measurement are consistent with the OTOP original reservoir pressure of 2,250 psi (-5,000 TVDSS) and proximity to ongoing production. Additionally, extended pressure build ups in ODST-45A and ODST-46 of 1,834 psi and 1,822 psi (-5,000 TVDSS), respectively, suggest similar levels of depletion and continuity in this initial development area. Attachment C details the surveys and relevant data. Page 2 of 8 3.0 Results and Analysis of Production and Injection Log Surveys, Tracer Surveys, Observation Well Surveys and any Other Special Monitoring Resman surveillance equipment placed in the production liner of ODST-46 to assess oil and water production conformance along the lateral via target fluid tracers indicate limited oil production from the toe of the well with the majority of the oil production from the heel to the mid-point of the lateral. Data collected in both the Sikumi 1 well and Nuna 1 well operations have been very valuable in characterizing the OTOP and targeting additional development locations. The specific data from these wells remain confidential but have been supplied to the AOGCC. 4.0 Review of Pool Production Allocation Factors and Issues Over the Year Production from the Oooguruk-Nuiqsut, Oooguruk-Kuparuk and Oooguruk-Torok pools is commingled at the surface into a common production line. Allocation between the pools is based on ratio of total production for a pool to the total production for the Oooguruk Unit. The pool allocation factors for 2012 are: Oooguruk-Nuiqsut Pool: 62.1% Oooguruk-Kuparuk Pool: 30.1% Oooguruk-Torok Pool: 7.8% Theoretical production for individual wells for all pools is calculated on a daily basis. During 2012 wells were produced with chokes at 100% most of the time. Daily theoretical production for a well was calculated using the data from the most current well test and the amount of time a well was on production for a given day: oductionlDailyTheoreticaBOPDxDailyRate dayMinutes Minutes Welltest produced Pr)(1440 = The daily allocation factor for the unit is calculated by dividing the actual total production for the day by the sum of the theoretical daily production for each individual well. Daily allocated production is assigned to each well by multiplying its theoretical daily production by the daily allocation factor. The average daily allocation factor for 2012 was 0.98. Page 3 of 8 5.0 Reservoir Management Summary The AOGCC issued pool rules under Conservation Orders No. 645, 596 and 597 for the Oooguruk-Torok, Oooguruk-Kuparuk and Oooguruk-Nuiqsut reservoirs, respectively. While there is no subsurface commingling, unitized substances produced from the three oil pools are commingled on the surface. There are two producing and one Torok injection wells. An additional producer, ODST-47 was drilled, completed and awaiting fracture stimulation. Page 4 of 8 ATTACHMENT A Voidage Balance by Month of Produced and Injected Fluids 2012 Page 5 of 8 ATTACHMENT B Map of Torok Well Locations Page 6 of 8 ATTACHMENT C 2012 Form 10-412 Pressure Report for Torok (Revised) Page 7 of 8 ATTACHMENT D Torok Reservoir Pressure Map – A Page 8 of 8 ATTACHMENT E ODST-46 Press Monitoring and Daily Injection Volume (AIO 37, Rule 9)