The Occurrence of Surface Casing Pressure in the Denver-Julesburg Basin

Transcription

1 The Occurrence of Surface Casing Pressure in the Denver-Julesburg Basin (Airwatergas.org) Greg Lackey, Harihar Rajaram, Owen A. Sherwood, Troy L. Burke and Joseph N. Ryan

2 Surface Casing Pressure Undesired buildup of pressure in the annulus between the surface casing and the next smaller diameter casing string

3 Surface Casing Pressure Undesired buildup of pressure in the annulus between the surface casing and the next smaller diameter casing string Bradenhead pressure, sustained casing pressure, sustained annular pressure, casing head pressure, surface casing vent flow

4 Surface Casing Pressure Undesired buildup of pressure in the annulus between the surface casing and the next smaller diameter casing string Bradenhead pressure, sustained casing pressure, sustained annular pressure, casing head pressure, surface casing vent flow Bradenhead tests

5 Goals Use data collected by the Colorado Oil and Gas Conservation Commission (COGCC) to assess the occurrence of surface casing pressure (SCP) in the Denver-Julesburg (DJ) Basin.

6 Goals Use data collected by the Colorado Oil and Gas Conservation Commission (COGCC) to assess the occurrence of surface casing pressure (SCP) in the Denver-Julesburg (DJ) Basin. Analyze the dataset to understand what factors contribute to the buildup of SCP.

7 Goals Use data collected by the Colorado Oil and Gas Conservation Commission (COGCC) to assess the occurrence of surface casing pressure (SCP) in the Denver-Julesburg (DJ) Basin. Analyze the dataset to understand what factors contribute to the buildup of SCP. Identify any potential relationships between the occurrence of SCP and documented stray gas incidents in the DJ Basin.

8 Well Leakage

9 Well Leakage 1. Casing leak 1.

10 Well Leakage 1. Casing leak Unknown intermediate 2.

11 Well Leakage 1. Casing leak Unknown intermediate 3. Faulty cement seal or improper cement coverage 2. 3.

12 Pressure Buildup 1. Casing leak 2. Unknown intermediate 3. Faulty cement seal or improper cement coverage P

13 Pressure Buildup 1. Casing leak P 2. Unknown intermediate Dissolved methane 3. Faulty cement seal or improper cement coverage

14 Pressure Buildup P 1. Casing leak 2. Unknown intermediate Gas phase methane 3. Faulty cement seal or improper cement coverage

15 Pressure Buildup 1. Casing leak P 2. Unknown intermediate Fracturing 3. Faulty cement seal or improper cement coverage

16 COGCC Bradenhead Testing Rules Rule 207 b. Bradenhead testing zones

17 COGCC Bradenhead Testing Rules Rule 207 b. Bradenhead testing zones Dec. 16, Wattenberg bradenhead testing policy

18 COGCC Bradenhead Testing Rules Rule 207 b. Bradenhead testing zones Dec. 16, Wattenberg bradenhead testing policy COGCC Communication Bradenhead tests requested for specific wells that appear to have production issues.

19 COGCC Bradenhead Testing Rules Rule 207 b. Bradenhead testing zones Dec. 16, Wattenberg bradenhead testing policy COGCC Communication Bradenhead tests requested for specific wells that appear to have production issues. Bradenhead monitoring May 29, Bradenhead monitoring during hydraulic fracturing treatments in greater Wattenberg area Rule 341. Bradenhead monitoring during well stimulation

20 COGCC Data 9,664 bradenhead tests in COGCC database

21 COGCC Data 9,664 bradenhead tests in COGCC database 7,344 able to be scraped

22 COGCC Data 9,664 bradenhead tests in COGCC database 7,344 able to be scraped 13,504 wells in testing zone

23 COGCC Data 9,664 bradenhead tests in COGCC database 7,344 able to be scraped 13,504 wells in testing zone 5,591 readable bradenhead tests in testing zones

24 COGCC Data 9,664 bradenhead tests in COGCC database 7,344 able to be scraped 13,504 wells in testing zone 5,591 readable bradenhead tests in testing zones Paired with well information scraped from COGCC online database

25 Refined dataset to: Data QAQC Wells and bradenhead tests completed before 2015 Wells that have been operational at some point

26 Refined dataset to: Data QAQC Wells and bradenhead tests completed before 2015 Wells that have been operational at some point Assessed validity of: 50 random wells and associated documents (100%) 164 bradenhead tests with initial bradenheads above the 98 th percentile (100%)

27 SCP Occurrence 1034 kpa (150 psi) All Wells Wattenberg: 19,841 TZ: 15,463 Readable Tests: 5,368

28 SCP Occurrence All Wells Wattenberg: 19,841 TZ: 15,463 Readable Tests: 5,368

29 SCP Occurrence 9.4% 3.7% 2.9% All Wells Wattenberg: 19,841 TZ: 15,463 Readable Tests: 5,368

30 49 th US Rock Mechanics Geomechanics Symposium June 28 July 1, 2015 GWPC Underground Injection Conference February 23-25, 2016 Geographic Occurrence

31 49 th US Rock Mechanics Geomechanics Symposium June 28 July 1, 2015 GWPC Underground Injection Conference February 23-25, 2016 Geographic Occurrence

32 Geographic Occurrence High SCP Region

33 Geographic Occurrence Inside: 9.2% wells above 1034 kpa High SCP Region

34 Geographic Occurrence Inside: 9.2% wells above 1034 kpa Outside: 2.0% of wells above 1034 kpa High SCP Region

35 Well Types Vertical Deviated/Directional Horizontal

36 SCP > 1000 kpa by Well Type 5% 17.3% 13.4% Inside High SCP Region

37 SCP > 1000 kpa by Well Type 5% 17.3% 13.4% 0.9% 4% 2.4% Inside High SCP Region Outside High SCP Region

38 Removed for analyses: Data QAQC Wells with incomplete well data Wells with inconsistent well data

39 Removed for analyses: Data QAQC Wells with incomplete well data Wells with inconsistent well data New numbers: 13,504 10,366 wells in bradenhead testing zone 5,591 4,419 readable tests in test zone

40 Well Construction Meets current regulations

41 Well Construction Fully cemented

42 Well Construction Short surface casing

43 Well Construction Uncemented Sussex

44 Well Construction Uncemented Niobrara

45 Well Construction Inside High SCP Region Outside High SCP Region

46 SCP > 1034 kpa by Well Construction 3.9% 0.7% 1.5% 0.5% 7% 5% 3.8% 9.6% 0.7% 0.3% Inside High SCP Region Outside High SCP Region

47 SCP > 1034 kpa by Well Construction 3.9% 0.7% 1.5% 0.5% 7% 5% 3.8% 9.6% 0.7% 0.3% Inside High SCP Region Outside High SCP Region

48 SCP > 1034 kpa by Well Construction 3.9% 0.7% 1.5% 0.5% 7% 5% 3.8% 9.6% 0.7% 0.3% Inside High SCP Region Outside High SCP Region

49 SCP > 1034 kpa by Well Construction 5% 21.6% 16.8% 6.3% 0.8% 2.4% 6.3% 0% 0% 0% Inside High SCP Region Outside High SCP Region

50 SCP > 1034 kpa by Well Construction 5% 21.6% 16.8% 6.3% 0.8% 2.4% 6.3% 0% 0% 0% Inside High SCP Region Outside High SCP Region

51 SCP > 1034 kpa by Well Construction 11.9% 13% 2.5% 2.6% 16.7% Inside High SCP Region Outside High SCP Region

52 SCP > 1034 kpa by Well Construction 11.9% 13% 2.5% 2.6% 16.7% Inside High SCP Region Outside High SCP Region

53 Conclusions Wells that have exhibited SCP above 150 psi: 811 (2.9%) to 2,627(9.4%) (%Wattenberg wells - %Readable tests)

54 Conclusions Wells that have exhibited SCP above 150 psi: 811 (2.9%) to 2,627(9.4%) (%Wattenberg wells - %Readable tests) Wells that have exhibited SCP above 0 psi: 3,605(12.9%) to 11,796(42.2%)

55 Conclusions Wells that have exhibited SCP above 150 psi: 811 (2.9%) to 2,627(9.4%) (%Wattenberg wells - %Readable tests) Wells that have exhibited SCP above 0 psi: 3,605(12.9%) to 11,796(42.2%) Factors that influence SCP: Geographic location Significantly higher % in high bradenhead region (9.2% vs. 2%)

56 Conclusions Wells that have exhibited SCP above 150 psi: 811 (2.9%) to 2,627(9.4%) (%Wattenberg wells - %Readable tests) Wells that have exhibited SCP above 0 psi: 3,605(12.9%) to 11,796(42.2%) Factors that influence SCP: Geographic location Significantly higher % in high bradenhead region (9.2% vs. 2%) Well type Higher percentage of deviated wells over 150 psi(7.3%-20.4%) Horizontal (3%-15.2%), vertical (1.6%-4.8%)

57 Conclusions Wells that have exhibited SCP above 150 psi: 811 (2.9%) to 2,627(9.4%) (%Wattenberg wells - %Readable tests) Wells that have exhibited SCP above 0 psi: 3,605(12.9%) to 11,796(42.2%) Factors that influence SCP: Geographic location Significantly higher % in high bradenhead region (9.2% vs. 2%) Well type Higher percentage of deviated wells over 150 psi(7.3%-20.4%) Horizontal (3%-15.2%), vertical (1.6%-4.8%) Well construction Legacy vertical wells Many properly constructed

58 Additional statistical tests: Continuing Work

59 Additional statistical tests: Continuing Work Well density Well age Well depth Well length Number of completed formations Number of treatments Drilling activity in the basin Gas/oil ratio Formation pressure Operator Produced water Time for well completion

60 Extra Slides 49 th US GWPC Rock Mechanics Underground Geomechanics Injection Conference Symposium February June 23-25, 28 July , 2015

61 Injection wells 14 in bradenhead test zone 0 with bradenhead pressure

62 Bradenhead tests in relation to completion Only 366 bradenhead tests within first year of well completion

63 Well Construction Surface casing: 50 ft (15.24 m)

64 Well Construction Surface casing: 50 ft (15.24 m) Production casing cement: 200 ft (60.96 m)

65 Well Construction Uncemented open annulus

66 Pressure Distribution

67 Pressure Distribution

68 Well Construction 16.5% 7.9% 22.7% 2.1% 31.42% Greater than ~7 kpa (1 Psi)

69 Well Construction 0.6% 0.9% 0.7% 0% 8.5% Greater than ~1034 kpa (150 Psi)

70 Bradenhead Tests vs. Time

71 Well Construction 27.3% 23.9% 24% 29.8% 14.2% Greater than ~7 kpa (1 Psi)

72 Well Construction 39.7% 24.4% 32.8% 15% 42.2% Greater than ~7 kpa (1 Psi)

73 Well Construction 47.5% 53.5% 0% 44.4% Greater than ~7 kpa (1 Psi)

74 SCP Occurrence 42.2% 16.1% 12.9% All Wells Wattenberg: 19,841 TZ: 15,463 Readable Tests: 5,368

75 SCP Occurrence by Well Type 34.3% 12.6% 11.3% Vertical Wells Wattenberg: 27,952 TZ: 9,723 Readable Tests: 3,687

76 SCP Occurrence by Well Type 58.7% 26.3% 20.8% Deviated/Directional (non-horizontal) Wells Wattenberg: 4,292 TZ: 3,433 Readable Tests: 1,380

77 SCP Occurrence by Well Type 62.7% 20.2% 12.1% Horizontal Wells Wattenberg: 2,389 TZ: 1,440 Readable Tests: 411

78 Pre-QAQC Data QAQC Post-QAQC Wells in TZ: 13,504 Readable tests in TZ: 5,591 Wells in TZ: 10,366 Readable tests in TZ: 4,419

79 Bradenhead Tests vs. Time by Type

80 US Crude Oil (thousand barrel/year) 49 th US GWPC Rock Mechanics Underground Geomechanics Injection Conference Symposium February June 23-25, 28 July , 2015 US Natural Gas (million cubic feet/year) Oil and Gas Production Increased interest in environmental impacts of oil and gas drilling. Focus on stray gas and well integrity Year Oil Natural Gas

81 COGCC Data Electronically scraped records for all wells in the DJ Basin

82 COGCC Data Electronically scraped records for all wells in the DJ Basin USGS point service

83 COGCC Data Electronically scraped records for all wells in the DJ Basin USGS point service Division of Water Resources aquifer determination tool

84 SCP Geographic Distribution Wells with SCP > 0 kpa: 3,818

85 SCP Occurrence by Well Type

86 SCP Occurrence by Well Type Vertical Wells Wattenberg: 27,952 TZ: 9,723 Readable Tests: 3,687

87 SCP Occurrence by Well Type 4.8% 1.9% 1.6% Vertical Wells Wattenberg: 27,952 TZ: 9,723 Readable Tests: 3,687

88 SCP Occurrence by Well Type Deviated/Directional (non-horizontal) Wells Wattenberg: 4,292 TZ: 3,433 Readable Tests: 1,380

89 SCP Occurrence by Well Type 20.4% 9.0% 7.3% Deviated/Directional (non-horizontal) Wells Wattenberg: 4,292 TZ: 3,433 Readable Tests: 1,380

90 SCP Occurrence by Well Type Horizontal Wells Wattenberg: 2,389 TZ: 1,440 Readable Tests: 411

91 SCP Occurrence by Well Type 15.2% 4.9% 3.0% Horizontal Wells Wattenberg: 2,389 TZ: 1,440 Readable Tests: 411

92 SCP Occurrence by Well Type Deviated and horizontal wells are developing SCP at greater rates than vertical wells in the bradenhead TZ.

93 Pressure Distribution

94 Bradenhead Testing Bradenhead - the annular space between the surface casing and the next smaller diameter casing string.

95 Bradenhead Testing Bradenhead - the annular space between the surface casing and the next smaller diameter casing string. 30 min. pressure bleed from annular valve

96 Bradenhead Testing Bradenhead - the annular space between the surface casing and the next smaller diameter casing string. 30 min. pressure bleed from annular valve Record production tubing, casing and bradenhead pressures every 5 minutes during test.