WELL · 42-255-37621 · DISTRICT 2

Forister-Janysek Unit #4H

Y

Karnes County · Eagleville (Eagle Ford-2) field · Producing  · Horizontal

Forister-Janysek Unit #4H (API 42-255-37621) is a horizontal well in Karnes County operated by Marathon Oil EF LLC, completed March 3, 2023 and listed as producing on the RRC schedule.

The RRC has issued one drilling permit, issued September 19, 2022, permitted to 22,000 ft.

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

Its lease has reported 1.35M barrels of oil and 1.64M mcf of gas since March 2012, last reporting in July 2026. The lease carries 4 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 LLCSep 19, 2022
22,000
total depth, ft
1
permits on file
Sep 19, 2022
last permit issued
Mar 3, 2023
completed
1.35M
cumulative oil, bbl
1.64M
cumulative gas, mcf

PRODUCTION FROM PDQ LEASE REPORTS · Mar 2012 THROUGH Jul 2026

Regulatory status · RRC wellbore file

Schedule
ON SCHEDULE
Completed
Mar 3, 2023
Shut in
—
Plugged
—

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

Surface location

28.885478, -97.999700

Google Maps ↗

Permit surface location from the RRC GIS record, in Karnes 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 4 wells in total, so volumes are shared.Why →

LeaseFieldReporting operatorWellsOil, bblGas, mcfReported
Forister-Janysek Unit O-2-10009Eagleville (Eagle Ford-2)Marathon Oil EF LLC41.35M1.64MMar 2012 – Jul 2026

Oil, barrels lease total

Last 12 months 62,990 · prior 12 86,952(-28%)

05K10K15K202420252026

Gas, mcf lease total

Last 12 months 57,483 · prior 12 96,362(-40%)

010K20K30K202420252026

Chain of custody

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

  1. 1Marathon Oil EF LLCApr 2012 → Apr 2026

Permits

PermitTypeOperatorReceivedIssuedSpudDepth
883793-99DrillMarathon Oil EF LLCSep 8, 2022Sep 19, 2022Feb 23, 202322,000

Completions

CompletedLeaseFieldOperatorStatusDepth
—— O-2-10009————

Formation tops

As filed on W-2/G-1. Subsea from 414 ft elevation.Download CSV →

FormationMD ftSubsea
Queen City2,845-2,431
Reklaw3,391-2,977
Carrizo3,928-3,514
WilcoxWILCOX - DISPOSAL4,021-3,607
Austin ChalkAUSTIN CHALK - H2S10,853-10,439
Eagle FordEAGLE FORD - H2S11,081-10,667
EdwardsEDWARDS - H2S——
FrioFRIO - DISPOSAL——
SligoSLIGO - H2S——
YeguaYEGUA - DISPOSAL——

Perforations

Perforated and open-hole intervals.

FromToType
11,20514,755Perforated

Casing

Strings as reported, shallowest first.

Casing inSet atHole inCement
9.6255,56612.251,367 S
614,7558.752,220 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
00Jul 10, 2023Jun 20, 2023Yes
00Apr 26, 2023Apr 10, 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 →

Forister 541 a-B SA42-255-37622

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

Queen City2,845-2,431
Reklaw3,391-2,977
Carrizo3,928-3,514
Wilcox4,021-3,607
Austin Chalk10,816-10,402
Eagle Ford11,059-10,645
Edwards—
Frio—

10 TOPS · FIRST 8

Forister 541 Unit B42-255-37186

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

Queen City3,326-2,914
Reklaw3,921-3,509
Carrizo4,406-3,994
Wilcox7,086-6,674
Austin Chalk10,838-10,426
Eagle Ford11,086-10,674
Edwards—
Frio—

10 TOPS · FIRST 8

Forister 541 Unit B42-255-37187

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

Queen City3,326-2,913
Reklaw3,921-3,508
Carrizo4,406-3,993
Wilcox7,086-6,673
Austin Chalk10,847-10,434
Eagle Ford11,093-10,680
Sligo—
Yegua—

10 TOPS · FIRST 8

Forister 541 Unit B42-255-37188

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

Queen City3,326-2,913
Reklaw3,921-3,508
Carrizo4,406-3,993
Wilcox7,996-7,583
Austin Chalk10,857-10,444
Eagle Ford11,100-10,687
Sligo—
Edwards—

10 TOPS · FIRST 8

Forister 541 Unit B42-255-37189

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

Queen City3,326-2,913
Reklaw3,921-3,508
Carrizo4,406-3,993
Wilcox7,996-7,583
Austin Chalk10,872-10,459
Eagle Ford11,335-10,922
Yegua—
Edwards—

10 TOPS · FIRST 8

Forister 541 B-M. Moczygemba SA42-255-37190

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

Queen City3,326-2,912
Reklaw3,921-3,507
Carrizo4,406-3,992
Wilcox7,086-6,672
Austin Chalk10,886-10,472
Eagle Ford11,130-10,716
Edwards—
Frio—

10 TOPS · FIRST 8

Forister-541 Unit A42-255-36555

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

Yegua1,369-962
Queen City3,385-2,978
Reklaw3,720-3,313
Carrizo4,515-4,108
Wilcox5,765-5,358
Austin Chalk10,810-10,403
Eagle Ford11,046-10,639
Edwards—

10 TOPS · FIRST 8

Forister-541 Unit A42-255-36556

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

Queen City3,385-2,978
Reklaw3,720-3,313
Carrizo4,515-4,108
Wilcox5,765-5,358
Austin Chalk10,790-10,383
Eagle Ford11,029-10,622
Sligo—
Edwards—

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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