WELL · 42-177-34598 · DISTRICT 1

Barnhart (Ef)-J.M. Preston SA9 #47H

Y

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

Barnhart (EF)-J.M. Preston Sa9 #47H (API 42-177-34598) is a horizontal well in Gonzales County operated by Marathon Oil EF LLC, completed October 10, 2023 and listed as producing on the RRC schedule.

The RRC has issued one drilling permit, issued March 9, 2023, permitted to 26,000 ft.

Completion filings report 11 formation tops, including Sparta, Queen City, Reklaw, Carrizo.

Its lease has reported 155K barrels of oil and 198K mcf of gas since August 2023, last reporting in July 2026.

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 LLCMar 9, 2023
26,000
total depth, ft
1
permits on file
Mar 9, 2023
last permit issued
Oct 10, 2023
completed
155K
cumulative oil, bbl
198K
cumulative gas, mcf

PRODUCTION FROM PDQ LEASE REPORTS · Aug 2023 THROUGH Jul 2026

Regulatory status · RRC wellbore file

Schedule
ON SCHEDULE
Completed
Oct 10, 2023
Shut in
—
Plugged
—

Operator's P-5 on the schedule: Active (A)

Surface location

29.259464, -97.472480

Google Maps ↗

Permit surface location from the RRC GIS record, in Gonzales 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; this well is the only one on it.Why →

LeaseFieldReporting operatorWellsOil, bblGas, mcfReported
Barnhart (Ef)-J.M. Preston SA9 O-1-21156Eagleville (Eagle Ford-1)Marathon Oil EF LLC1155K198KAug 2023 – Jul 2026

Oil, barrels lease total

Last 12 months 19,863 · prior 12 38,697(-49%)

010K20K30K202420252026

Gas, mcf lease total

Last 12 months 25,808 · prior 12 56,293(-54%)

010K20K30K202420252026

Chain of custody

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

  1. 1Marathon Oil EF LLCAug 2023 → Apr 2026

Permits

PermitTypeOperatorReceivedIssuedSpudDepth
888758-99DrillMarathon Oil EF LLCMar 6, 2023Mar 9, 2023Jul 10, 202326,000

Completions

CompletedLeaseFieldOperatorStatusDepth
—— O-1-21156————

Formation tops

As filed on W-2/G-1. Subsea from 226 ft elevation.Download CSV →

FormationMD ftSubsea
Sparta1,334-1,108
Queen City2,685-2,459
Reklaw3,037-2,811
Carrizo3,705-3,479
WilcoxWILCOX - DISPOSAL3,805-3,579
Anacacho10,393-10,167
Austin ChalkAUSTIN CHALK - H2S10,638-10,412
Eagle FordEAGLE FORD - H2S11,234-11,008
BudaBUDA - H2S, DISPOSAL——
EdwardsEDWARDS - H2S——
Navarro——

Perforations

Perforated and open-hole intervals.

FromToType
11,53219,040Perforated

Casing

Strings as reported, shallowest first.

Casing inSet atHole inCement
9.6254,59512.251,130 S
619,0408.753,073 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
00Feb 23, 2024Feb 5, 2024—
00Nov 29, 2023Oct 16, 2023Yes

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 →

Barnhart (Ef)-J.M. Preston SA842-177-34597

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

Reklaw3,037-2,811
Carrizo3,705-3,479
Wilcox3,805-3,579
Austin Chalk10,648-10,422
Eagle Ford11,259-11,033
Buda—
Edwards—
Navarro—

Barnhart (Ef)-J.M. Preston SA742-177-34596

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

Sparta1,334-1,108
Queen City2,685-2,459
Reklaw3,037-2,811
Carrizo3,705-3,479
Wilcox3,805-3,579
Austin Chalk10,651-10,425
Eagle Ford11,259-11,033
Buda—

10 TOPS · FIRST 8

Barnhart (EF)42-177-34138

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

Reklaw3,106-2,864
Carrizo3,703-3,461
Wilcox4,790-4,548
Austin Chalk10,604-10,362
Eagle Ford11,259-11,017
Buda—
Navarro—
Edwards—

Barnhart (EF)42-177-34139

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

Reklaw3,106-2,864
Carrizo3,703-3,461
Wilcox4,790-4,548
Austin Chalk10,567-10,325
Eagle Ford11,215-10,973
Edwards—
Navarro—
Buda—

Barnhart Grand F Unit-E Unit SA42-177-34519

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

Reklaw3,310-3,063
Wilcox3,875-3,628
Carrizo3,875-3,628
Austin Chalk11,072-10,825
Eagle Ford11,792-11,545
Edwards—
Buda—
Navarro—

Barnhart (EF) F Unit42-177-34520

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

Reklaw3,310-3,063
Carrizo3,875-3,628
Wilcox4,021-3,774
Austin Chalk11,075-10,828
Eagle Ford11,793-11,546
Narvarro—
Navarro—
Edwards—

10 TOPS · FIRST 8

Barnhart (EF) F Unit42-177-34521

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

Reklaw3,310-3,063
Carrizo3,875-3,628
Wilcox4,021-3,774
Austin Chalk11,087-10,840
Eagle Ford11,753-11,506
Buda—
Navarro—
Edwards—

Barnhart (EF) F Unit-A Unit SA42-177-34522

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

Reklaw3,310-3,063
Carrizo3,875-3,628
Wilcox4,021-3,774
Austin Chalk11,079-10,832
Eagle Ford11,751-11,504
Edwards—
Navarro—
Buda—

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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