WELL · 42-255-36375 · DISTRICT 2

Spahn-Mikkelson Unit #3H

Y

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

Spahn-Mikkelson Unit #3H (API 42-255-36375) is a horizontal well in Karnes County operated by Marathon Oil EF LLC, completed January 16, 2020 and listed as producing on the RRC schedule.

The RRC has issued one drilling permit, issued March 19, 2019, permitted to 22,000 ft.

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

Its lease has reported 1.01M barrels of oil and 1.49M mcf of gas since May 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

Houston, TX · P-5 Y, filed Aug 4, 2025 · 3,191 permits on file · (800) 332-9449

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 19, 2019
22,000
total depth, ft
1
permits on file
Mar 19, 2019
last permit issued
Jan 16, 2020
completed
1.01M
cumulative oil, bbl
1.49M
cumulative gas, mcf

PRODUCTION FROM PDQ LEASE REPORTS · May 2012 THROUGH Jul 2026

Regulatory status · RRC wellbore file

Schedule
ON SCHEDULE
Completed
Jan 16, 2020
Shut in
—
Plugged
—

Operator's P-5 on the schedule: Active

Surface location

28.883656, -97.937608

OpenStreetMap → ·  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
Spahn-Mikkelson Unit O-2-10060Eagleville (Eagle Ford-2)Marathon Oil EF LLC41.01M1.49MMay 2012 – Jul 2026

Oil, barrels lease total

Last 12 months 27,367 · prior 12 25,496(+7%)

05K10K202420252026

Gas, mcf lease total

Last 12 months 41,250 · prior 12 40,815(+1%)

05K10K15K202420252026

Chain of custody

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

  1. 1Marathon Oil EF LLCMay 2012 → Apr 2026

Permits

PermitTypeOperatorReceivedIssuedSpudDepth
850510-99DrillMarathon Oil EF LLCFeb 28, 2019Mar 19, 2019Sep 30, 201922,000

Completions

CompletedLeaseFieldOperatorStatusDepth
—— O-2-10060————

Formation tops

As filed on W-2/G-1. Subsea from 347 ft elevation.Download CSV →

FormationMD ftSubsea
YeguaYEGUA - DISPOSAL1,625-1,278
Queen City3,796-3,449
Reklaw4,230-3,883
Carrizo4,779-4,432
WilcoxWILCOX - DISPOSAL6,093-5,746
Austin ChalkAUSTIN CHALK - H2S11,545-11,198
Eagle FordEAGLE FORD - H2S11,768-11,421
EdwardsEDWARDS - H2S——
FrioFRIO - DISPOSAL——
SligoSLIGO - H2S——

Perforations

Perforated and open-hole intervals.

FromToType
11,88517,737Perforated

Casing

Strings as reported, shallowest first.

Casing inSet atHole inCement
9.6255,62712.251,642 S
5.517,8448.752,795 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
00May 13, 2020Jan 30, 2020Yes
00Jan 22, 2020Nov 6, 2019Yes
00Aug 14, 2019Aug 2, 2019Yes

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 neighbours, subsea-aligned so they line up regardless of surface terrain.

Open the cross-section →

Spahn-Mikkelson Unit42-255-36376

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

Yegua1,625-1,278
Queen City3,796-3,449
Reklaw4,230-3,883
Carrizo4,779-4,432
Wilcox6,093-5,746
Austin Chalk11,560-11,213
Eagle Ford11,801-11,454
Frio—

10 TOPS · FIRST 8

Carter Unit42-255-36373

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

Yegua1,625-1,277
Queen City3,796-3,448
Reklaw4,230-3,882
Carrizo4,779-4,431
Wilcox6,093-5,745
Austin Chalk11,575-11,227
Eagle Ford11,789-11,441
Edwards—

10 TOPS · FIRST 8

Carter Unit42-255-36374

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

Yegua1,625-1,277
Queen City3,796-3,448
Reklaw4,230-3,882
Carrizo4,779-4,431
Wilcox6,093-5,745
Austin Chalk11,591-11,243
Eagle Ford11,817-11,469
Frio—

10 TOPS · FIRST 8

RSW-Mikkelson-Rogers SA42-255-36563

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

Yegua1,981-1,648
Queen City3,996-3,663
Reklaw4,332-3,999
Carrizo5,127-4,794
Wilcox6,377-6,044
Austin Chalk11,438-11,105
Eagle Ford11,661-11,328
Sligo—

10 TOPS · FIRST 8

Rippstein-Mikkelson Unit42-255-36561

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

Yegua1,981-1,648
Queen City3,996-3,663
Reklaw4,332-3,999
Carrizo5,127-4,794
Wilcox6,377-6,044
Austin Chalk11,459-11,126
Eagle Ford11,684-11,351
Sligo—

10 TOPS · FIRST 8

Rippstein-Mikkelson Unit42-255-36562

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

Yegua1,981-1,648
Queen City3,996-3,663
Reklaw4,332-3,999
Carrizo5,127-4,794
Wilcox6,377-6,044
Austin Chalk11,442-11,109
Eagle Ford11,666-11,333
Edwards—

10 TOPS · FIRST 8

Mikkelson-Witte Unit42-255-38056

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

Queen City3,927-3,518
Reklaw4,430-4,021
Carrizo4,950-4,541
Wilcox6,222-5,813
Austin Chalk11,734-11,325
Eagle Ford11,960-11,551
Yegua—
Edwards—

10 TOPS · FIRST 8

Rippstein Mikkelson-Witte SA142-255-38055

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

Queen City3,927-3,518
Reklaw4,430-4,021
Carrizo4,950-4,541
Wilcox6,222-5,813
Austin Chalk11,725-11,316
Eagle Ford11,960-11,551
Yegua—
Frio—

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

Developers: this page as JSON is GET /v1/data/wells/25536375, documented in the API reference.