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Texas oil lease

Producing

GUAJILLO UNIT 8 SOUTH

Guajillo Unit 8 South is an oil lease in Atascosa County, Texas, operated by Marathon Oil Ef LLC in the Eagleville (Eagle Ford-1) field.

5 wells

21,636bbl oil, last 12 months−35% vs prior year
Operator
Marathon Oil Ef LLC
County
Atascosa County
Field
Eagleville (Eagle Ford-1)
RRC lease
01-19278

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Where it sits

This county

Atascosa CountyAtascosaWilsonMedinaKarnesFrioBexarAtascosa County
Atascosa County
Gas, last 12 months
28,454 mcf
Oil in Jul 2026
1,549 bbl

Production by month

Oil output fell 35% over the last 12 months

  • Oil (bars)
  • Gas (line)
  • Last 12 months
Oil output fell 35% over the last 12 monthsMonthly oil production and gas for GUAJILLO UNIT 8 SOUTH, Aug 2023 to Jul 2026. Oil output fell 35% over the last 12 months. 21,636 bbl in the 12 months through Jul 2026, against 33,227 bbl in the 12 months before.Last 12 months: 21,636 bblbbl per monthmcf per month001,0002,5002,0005,0003,0007,5004,00010k5,00012.5kOct 23Jan 24AprJulOctJan 25AprJulOctJan 26AprJul
Oil output fell 35% over the last 12 monthsMonthly oil production and gas for GUAJILLO UNIT 8 SOUTH, Aug 2023 to Jul 2026. Oil output fell 35% over the last 12 months. 21,636 bbl in the 12 months through Jul 2026, against 33,227 bbl in the 12 months before.Last 12 monthsbbl per monthmcf per month001,0002,5002,0005,0003,0007,5004,00010k5,00012.5kJan 24JulJan 25JulJan 26Jul

SourceTexas Railroad Commission Production Data Query, through Jul 2026.

Where the gas went

69% of the gas went to a processing plant in the last 12 months

Flaring peaked at 4.5% of the gas in Sep 2023.

  • Processing plant (3)
  • Lease fuel (1)
  • Flared (4)
69% of the gas went to a processing plant in the last 12 monthsShare of GUAJILLO UNIT 8 SOUTH gas by disposition code each month, Aug 2023 to Jul 2026. 69% of the gas went to a processing plant in the last 12 months. Flaring peaked at 4.5% of the gas in Sep 2023.Share of the lease’s gas by disposition code, per month0%50%100%Flared 4.5%Oct 23Jan 24AprJulOctJan 25AprJulOctJan 26AprJul
69% of the gas went to a processing plant in the last 12 monthsShare of GUAJILLO UNIT 8 SOUTH gas by disposition code each month, Aug 2023 to Jul 2026. 69% of the gas went to a processing plant in the last 12 months. Flaring peaked at 4.5% of the gas in Sep 2023.Share of gas by disposition code0%50%100%Flared 4.5%Jan 24JulJan 25JulJan 26Jul

SourceTexas Railroad Commission Production Data Query, through Jul 2026.

  • Processing plant (3)

    69% · 19,761 mcf

  • Lease fuel (1)

    29% · 8,183 mcf

  • Flared (4)

    1.8% · 510 mcf

1.8% of the gas flared in the last 12 months. 6 months above 3%.

5 wells on this lease

Wells on GUAJILLO UNIT 8 SOUTH
API numberWell no.Status
42-013-354132HActive
42-013-354141HActive
42-013-354153HActive
42-013-354164HActive
42-013-354175HActive

SourceTexas Railroad Commission Wellbore Query.

Buyers and gatherers

Companies named on the Form P-4, by product
CompanyProductRoleShare%FromUntil
Harvest Midstream CompanyOilGathers20Jul 1, 2022–
Reynolds Energy Transport LLCOilGathers20Jul 1, 2022–
Shell Trading (Us) CompanyOilGathers20Jul 1, 2022–
Statewide Crude Inc.OilGathers20Jul 1, 2022–
Valero Marketing and Supply Co.OilGathers20Jul 1, 2022–
Marathon Oil Ef LLCCasinghead gasBuys100Dec 29, 2017–
Marathon Oil Ef LLCCasinghead gasGathers100Dec 29, 2017–
Gulfmark Energy, Inc.OilGathers15Dec 29, 2017Jul 1, 2022
Harvest Midstream CompanyOilGathers5Sep 1, 2018Jul 1, 2022
Marathon Oil Ef LLCOilGathers1Dec 29, 2017Jul 1, 2022
Shell Trading (Us) CompanyOilGathers3Dec 29, 2017Jul 1, 2022
Statewide Crude Inc.OilGathers5Dec 29, 2017Jul 1, 2022
Valero Marketing and Supply Co.OilGathers71Dec 29, 2017Jul 1, 2022

SourceRailroad Commission Form P-4 file, Sep 24, 2026 (source).

Who buys my oilOil price check

264.78 acres on the newest permit

  • Worth asking

    A Rule 37 case is listed

    The RRC permit records list a Rule 37 case. This does not establish your royalty share. Ask for the permit and unit plat for your well.

Check your decimal on this lease
Permits for Guajillo Unit 8 South
API numberWell no.Acreson the permit
42-013-354132H264.78
42-013-354141H264.78
42-013-354153H264.78
42-013-354164H264.78
42-013-354175H264.78

SourceRailroad Commission drilling permits, Oct 3, 2026 (source 1, source 2).

Unit decimal checker

What ConocoPhillips told investors it received

Marathon Oil Ef LLC is linked to ConocoPhillips (MRO).
Realized prices reported by ConocoPhillips
QuarterOil$ per bblFiling
Q2 2026$99.40SEC filing
Q1 2026$73.47SEC filing
Q3 2025$66.13SEC filing
Q2 2025$64.23SEC filing
Q1 2025$71.65SEC filing

SourceConocoPhillips quarterly reports, SEC EDGAR, company-wide averages before hedging.

Estimate your royalty

36 months, newest first

Ledger for GUAJILLO UNIT 8 SOUTH
MonthOil producedbblOil soldbblGas producedmcfGas soldmcf, codes 2+3FlaredmcfWTI$/bblHenry Hub$/MMBtu
Jul 20261,5491,5351,9671,28824$80.46$2.89
Jun 20268879151,32788913$84.81$3.15
May 20261,8771,9212,6431,84444$102.13$2.94
Apr 20263,6923,6473,4712,48030$100.32$2.77
Mar 20261,3811,4002,5421,73452$91.38$3.04
Feb 20262,1402,0971,7811,26621$64.51$3.62
Jan 20261,6491,6412,6901,88918$60.04$7.72
Dec 20251,5961,5862,8292,04320$57.97$4.26
Nov 20259919991,7181,19761$60.06$3.79
Oct 20251,5491,5522,5661,88636$60.89$3.19
Sep 20251,5991,6072,1221,47072$63.96$2.97
Aug 20252,7262,7212,7981,775119$64.86$2.91
Jul 20252,1322,1305,7993,623108$68.39$3.20
Jun 20252,2712,2784,7362,866129$68.17$3.02
May 20252,7622,7704,7002,866120$62.17$3.12
Apr 20252,3582,3475,3893,390109$63.54$3.42
Mar 20253,0593,0567,5704,916155$68.24$4.12
Feb 20252,6672,6756,5904,29582$71.53$4.19
Jan 20253,0573,0367,4704,830238$75.74$4.13
Dec 20243,0173,0166,7524,551129$70.12$3.01
Nov 20242,7692,7665,9994,215105$69.95$2.12
Oct 20243,2933,2979,3156,865147$71.99$2.20
Sep 20242,8632,8688,6506,606139$70.24$2.28
Aug 20242,9792,9756,8625,30770$76.68$1.99
Jul 20242,8862,88710,9078,59994$81.80$2.07
Jun 20242,7702,7998,1256,011135$79.77$2.54
May 20243,9383,93111,9556,611306$80.02$2.12
Apr 20243,4943,4917,0493,556247$85.35$1.60
Mar 20243,4543,4538,1874,74791$81.28$1.49
Feb 20244,4154,4189,6316,284139$77.25$1.72
Jan 20243,7353,7447,8804,415187$74.15$3.18
Dec 20233,9773,96210,2226,667179$71.90$2.52
Nov 20233,0363,03510,5027,002188$77.69$2.71
Oct 20233,9963,99110,6637,136251$85.64$2.98
Sep 20233,0723,0758,8075,535397$89.43$2.64
Aug 20233,5743,58010,4996,998176$81.39$2.58

Flared above 3%

SourceTexas Railroad Commission Production Data Query, through Jul 2026. Prices: EIA, through Aug 2026. Updated Oct 2, 2026.

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Nearby

This lease belongs to

OperatorMarathon Oil Ef LLCFieldEagleville (Eagle Ford-1)CountyAtascosa County

Marathon Oil Ef LLC in Atascosa County

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