TEXAS · WELLS · ATASCOSA COUNTY · GUAJILLO UNIT 8 NORTH LEASE · API 42-013-35544 · DISTRICT 01

Guajillo Unit 8 North #1H

Y

Atascosa County · Eagleville (Eagle Ford-1) field · Producing  · Horizontal

Guajillo Unit 8 North #1H (API 42-013-35544) is a horizontal well in Atascosa County operated by Marathon Oil EF LLC, completed August 20, 2018 and listed as producing on the RRC schedule.

The RRC has issued one drilling permit, issued November 3, 2017, permitted to 11,085 ft.

Completion filings report 10 formation tops, including Queen City, Reklaw, Carrizo, Wilcox.

Its lease has reported 1.14M barrels of oil and 1.51M mcf of gas since March 2018, last reporting in July 2026. The lease carries 5 wells, so these are lease totals, not this well alone.

Operator of record

Marathon Oil EF LLC

Based in
Houston, TX
P-5 status
Active (A)
P-5 last filed
Sep 26, 2025
Permits on file
3,191
Phone
(832) 486-2737

SOURCE · RRC EWA WELLBORE SCHEDULE

What each RRC source says

Wellbore scheduleMarathon Oil EF LLC
Production reportsMarathon Oil EF LLCthrough Apr 2026
Latest permitMarathon Oil EF LLCNov 3, 2017
11,085
total depth, ft
1
permits on file
Nov 3, 2017
last permit issued
Aug 20, 2018
completed
1.14M
cumulative oil, bbl
1.51M
cumulative gas, mcf

PRODUCTION FROM PDQ LEASE REPORTS · Mar 2018 THROUGH Jul 2026

Regulatory status · RRC wellbore file

Schedule
ON SCHEDULE
Completed
Aug 20, 2018
Shut in
—
Plugged
—

Operator's P-5 on the schedule: Active – Extension (X)

Surface location

28.659581, -98.276203

Google Maps ↗

Permit surface location from the RRC GIS record, in Atascosa County.

Lease production

PDQ LEASE REPORTS · REPORTED THROUGH APR 2026

Texas reports oil by lease, not by well. These are the lease this well is completed on; they carry 5 wells in total, so volumes are shared.Why →

LeaseFieldReporting operatorWellsOil, bblGas, mcfReported
Guajillo Unit 8 North O-1-19403Eagleville (Eagle Ford-1)Marathon Oil EF LLC51.14M1.51MMar 2018 – Jul 2026

Oil, barrels lease total

Last 12 months 28,797 · prior 12 35,091(-18%)

02K4K6K202420252026

Gas, mcf lease total

Last 12 months 30,068 · prior 12 54,850(-45%)

05K10K202420252026

Chain of custody

Every operator that reported production on this well's lease, in order.

  1. 1Marathon Oil EF LLCAug 2018 → Apr 2026

Permits

PermitTypeOperatorReceivedIssuedSpudDepth
832409-99DrillMarathon Oil EF LLCOct 25, 2017Nov 3, 2017Jul 29, 201822,000

Completions

CompletedLeaseFieldOperatorStatusDepth
Aug 20, 2018Guajillo Unit 8 North O-1-19403Eagleville (Eagle Ford-1)Marathon Oil EF LLCProducing11,085

Formation tops

As filed on W-2/G-1. Subsea from 248 ft elevation.Download CSV →

FormationMD ftSubsea
Queen City3,027-2,779
Reklaw3,389-3,141
Carrizo4,029-3,781
WilcoxWILCOX - DISPOSAL5,317-5,069
AnacachoANACACHO - H2S10,827-10,579
Austin ChalkAUSTIN CHALK - H2S, DISPOSAL11,056-10,808
Bartosh——
EscondidoESCONDIDO - H2S, DISPOSAL——
NavarroNAVARRO - H2S——
OlmosOLMOS - DISPOSAL——

Perforations

Perforated and open-hole intervals.

FromToType
11,59716,843Perforated

Casing

Strings as reported, shallowest first.

Casing inSet atHole inCement
9.6255,28412.251,744 S
5.516,9518.752,922 S

Completion filings

W-2 and G-1 reports on record in the RRC wellbore file, newest first. The suffix identifies the wellbore or completion event. About these reports →

SuffixFiledW-2 / G-1 dateLogs referenced
00Nov 12, 2018Sep 19, 2018Yes
00Oct 12, 2018Aug 29, 2018Yes

The source documents

Petrora holds the structured record. The scanned filings live at the RRC; these links open its search already filled in for this API.

Log images are in archives with no per-well link: the RRC's Neubus archive (2004 onward). then paste it into their search.

Nearby wells and their tops

NEAREST 8 LOCATED WELLS WITH TOPS · WITHIN 16 KM

Draw a cross-section

This well's tops beside its 5 nearest neighbors, subsea-aligned so they line up regardless of surface terrain.

Open the cross-section →

Guajillo Unit 8 North42-013-35545

0.0 KM · Marathon Oil EF LLC · Section with this well →

Queen City3,027-2,778
Reklaw3,389-3,140
Carrizo4,029-3,780
Wilcox5,317-5,068
Anacacho10,825-10,576
Austin Chalk11,053-10,804
Bartosh—
Escondido—

10 TOPS · FIRST 8

Guajillo Unit 8 North42-013-35546

0.0 KM · Marathon Oil EF LLC · Section with this well →

Queen City3,027-2,777
Reklaw3,389-3,139
Carrizo4,029-3,779
Wilcox5,317-5,067
Anacacho10,820-10,570
Austin Chalk11,052-10,802
Navarro—
Bartosh—

10 TOPS · FIRST 8

Guajillo Unit 8 North42-013-35547

0.0 KM · Marathon Oil EF LLC · Section with this well →

Queen City3,027-2,775
Reklaw3,389-3,137
Carrizo4,029-3,777
Wilcox5,317-5,065
Anacacho10,812-10,560
Austin Chalk11,044-10,792
Bartosh—
Navarro—

10 TOPS · FIRST 8

Guajillo Unit 8 North42-013-35548

0.0 KM · Marathon Oil EF LLC · Section with this well →

Queen City3,027-2,774
Reklaw3,389-3,136
Carrizo4,029-3,776
Wilcox5,317-5,064
Anacacho10,817-10,564
Austin Chalk11,044-10,791
Bartosh—
Olmos—

10 TOPS · FIRST 8

Guajillo Unit 8 South42-013-35414

0.1 KM · Marathon Oil EF LLC · Section with this well →

Queen City3,035-2,786
Reklaw3,396-3,147
Bartosh3,795-3,546
Carrizo4,036-3,787
Wilcox5,324-5,075
Navarro8,987-8,738
Olmos9,323-9,074
Anacacho10,804-10,555

10 TOPS · FIRST 8

Guajillo Unit 8 South42-013-35413

0.1 KM · Marathon Oil EF LLC · Section with this well →

Queen City3,035-2,785
Reklaw3,396-3,146
Bartosh3,795-3,545
Carrizo4,036-3,786
Wilcox5,324-5,074
Navarro8,987-8,737
Olmos9,323-9,073
Anacacho10,789-10,539

10 TOPS · FIRST 8

Guajillo Unit 8 South42-013-35415

0.1 KM · Marathon Oil EF LLC · Section with this well →

Queen City3,035-2,784
Reklaw3,396-3,145
Bartosh3,795-3,544
Carrizo4,036-3,785
Wilcox5,324-5,073
Navarro8,987-8,736
Olmos9,323-9,072
Anacacho10,800-10,549

10 TOPS · FIRST 8

Guajillo Unit 8 South42-013-35416

0.1 KM · Marathon Oil EF LLC · Section with this well →

Queen City3,035-2,784
Reklaw3,396-3,145
Bartosh3,795-3,544
Carrizo4,036-3,785
Wilcox5,324-5,073
Navarro8,987-8,736
Olmos9,323-9,072
Anacacho10,792-10,541

10 TOPS · FIRST 8

About this data

Permits from the RRC OGA049M master and daily daf420 files; wellbore and operator of record from the EWA schedule, weekly; completions, formation tops, casing, and perforations from the dbf900 wellbore file; production from PDQ lease reports, which lag two to three months; injection from UIC permits, H-10 reports, and TexNet daily volumes; earthquakes from the TexNet catalog.

New to these records? How to read a well page · API numbers · completion reports and tops · why production is by lease

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