WELL · 42-255-37509 · DISTRICT 2
Anzaldua Oxford-Martinez SA #1H
Karnes County · Eagleville (Eagle Ford-2) field · Producing · Horizontal
Anzaldua Oxford-Martinez SA #1H (API 42-255-37509) is a horizontal well in Karnes County operated by Marathon Oil EF LLC, completed February 12, 2023 and listed as producing on the RRC schedule.
The RRC has issued one drilling permit, issued June 6, 2022, permitted to 11,099 ft.
Completion filings report 10 formation tops, including Eagle Ford, Yegua, Queen City, Reklaw.
Its lease has reported 189K barrels of oil and 290K mcf of gas since July 2022, last reporting in July 2026.
Operator of record
- 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 schedule | Marathon Oil EF LLC |
| Production reports | Marathon Oil EF LLCthrough Apr 2026 |
| Latest permit | Marathon Oil EF LLCJun 6, 2022 |
- 11,099
- total depth, ft
- 1
- permits on file
- Jun 6, 2022
- last permit issued
- Feb 12, 2023
- completed
- 189K
- cumulative oil, bbl
- 290K
- cumulative gas, mcf
PRODUCTION FROM PDQ LEASE REPORTS · Jul 2022 THROUGH Jul 2026
Regulatory status · RRC wellbore file
- Schedule
- ON SCHEDULE
- Completed
- Feb 12, 2023
- Shut in
- —
- Plugged
- —
Operator's P-5 on the schedule: Active – Extension (X)
Surface location
28.868156, -98.011567
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; this well is the only one on it.Why →
| Lease | Field | Reporting operator | Wells | Oil, bbl | Gas, mcf | Reported |
|---|---|---|---|---|---|---|
| Anzaldua Oxford-Martinez SA O-2-12420 | Eagleville (Eagle Ford-2) | Marathon Oil EF LLC | 1 | 189K | 290K | Jul 2022 – Jul 2026 |
Oil, barrels lease total
Last 12 months 16,863 · prior 12 38,083(-56%)
Gas, mcf lease total
Last 12 months 35,823 · prior 12 63,153(-43%)
Chain of custody
Every operator that reported production on this well's lease, in order.
- 1Marathon Oil EF LLCFeb 2023 → Apr 2026
Permits
| Permit | Type | Operator | Received | Issued | Spud | Depth |
|---|---|---|---|---|---|---|
| 880438-99 | Drill | Marathon Oil EF LLC | May 23, 2022 | Jun 6, 2022 | Jan 23, 2023 | 22,000 |
Completions
| Completed | Lease | Field | Operator | Status | Depth |
|---|---|---|---|---|---|
| Feb 12, 2023 | Anzaldua Oxford-Martinez SA O-2-12420 | Eagleville (Eagle Ford-2) | Marathon Oil EF LLC | Producing | 11,099 |
Formation tops
As filed on W-2/G-1. Subsea from 445 ft elevation.Download CSV →
| Formation | MD ft | Subsea |
|---|---|---|
| Eagle FordEAGLE FORD - H2S | 1,128 | -683 |
| YeguaYEGUA - DISPOSAL | 1,535 | -1,090 |
| Queen City | 3,333 | -2,888 |
| Reklaw | 3,923 | -3,478 |
| Carrizo | 4,484 | -4,039 |
| WilcoxWILCOX - DISPOSAL | 5,743 | -5,298 |
| Austin ChalkAUSTIN CHALK - H2S | 11,062 | -10,617 |
| Eagle FordEAGLE FORD - H2S | 11,280 | -10,835 |
| EdwardsEDWARDS - H2S | — | — |
| FrioFRIO - DISPOSAL | — | — |
| SligoSLIGO - H2S | — | — |
Perforations
Perforated and open-hole intervals.
| From | To | Type |
|---|---|---|
| 11,720 | 17,138 | Perforated |
Casing
Strings as reported, shallowest first.
| Casing in | Set at | Hole in | Cement |
|---|---|---|---|
| 9.625 | 5,716 | 12.25 | 1,342 S |
| 6 | 17,137 | 8.75 | 2,655 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 →
| Suffix | Filed | W-2 / G-1 date | Logs referenced |
|---|---|---|---|
| 00 | Jun 1, 2023 | May 4, 2023 | Yes |
| 00 | Sep 12, 2022 | Aug 5, 2022 | Yes |
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.
- Wellbore filings for 42-255-37509 → W-2, G-1, plugging reports, as PDFs
- Completion packets for 42-255-37509 → scanned completion filings
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.
Anzaldua Oxford Unit42-255-37508
0.0 KM · Marathon Oil EF LLC · Section with this well →
| Yegua | 1,535 | -1,090 |
| Queen City | 3,333 | -2,888 |
| Reklaw | 3,923 | -3,478 |
| Carrizo | 4,484 | -4,039 |
| Wilcox | 5,743 | -5,298 |
| Austin Chalk | 11,041 | -10,596 |
| Eagle Ford | 11,249 | -10,804 |
| Sligo | — |
10 TOPS · FIRST 8
Anzaldua Oxford Unit42-255-37507
0.0 KM · Marathon Oil EF LLC · Section with this well →
| Yegua | 1,535 | -1,090 |
| Cook Mountain | 2,495 | -2,050 |
| Sparta | 3,066 | -2,621 |
| Queen City | 3,333 | -2,888 |
| Reklaw | 3,923 | -3,478 |
| Carrizo | 4,484 | -4,039 |
| Wilcox | 5,743 | -5,298 |
| Midway | 7,419 | -6,974 |
14 TOPS · FIRST 8
Davidson-Anzaldua-Creel SA42-255-37510
0.0 KM · Marathon Oil EF LLC · Section with this well →
| Yegua | 1,535 | -1,090 |
| Cook Mountain | 2,495 | -2,050 |
| Sparta | 3,066 | -2,621 |
| Queen City | 3,333 | -2,888 |
| Reklaw | 3,923 | -3,478 |
| Carrizo | 4,484 | -4,039 |
| Wilcox | 5,743 | -5,298 |
| Midway | 7,419 | -6,974 |
11 TOPS · FIRST 8
Davidson Oxford Unit42-255-36903
1.1 KM · Marathon Oil EF LLC · Section with this well →
| Yegua | 1,378 | -912 |
| Queen City | 3,433 | -2,967 |
| Reklaw | 3,976 | -3,510 |
| Carrizo | 4,433 | -3,967 |
| Wilcox | 5,755 | -5,289 |
| Austin Chalk | 10,926 | -10,460 |
| Eagle Ford | 11,142 | -10,676 |
| Sligo | — |
10 TOPS · FIRST 8
Davidson Oxford Unit42-255-36921
1.1 KM · Marathon Oil EF LLC · Section with this well →
| Yegua | 1,378 | -912 |
| Queen City | 3,433 | -2,967 |
| Reklaw | 3,976 | -3,510 |
| Carrizo | 4,433 | -3,967 |
| Wilcox | 5,755 | -5,289 |
| Austin Chalk | 10,916 | -10,450 |
| Eagle Ford | 11,135 | -10,669 |
| Edwards | — |
10 TOPS · FIRST 8
Davidson Oxford Unit42-255-36900
1.1 KM · Marathon Oil EF LLC · Section with this well →
| Yegua | 1,378 | -912 |
| Queen City | 3,433 | -2,967 |
| Reklaw | 3,976 | -3,510 |
| Carrizo | 4,433 | -3,967 |
| Wilcox | 5,755 | -5,289 |
| Austin Chalk | 10,934 | -10,468 |
| Eagle Ford | 11,142 | -10,676 |
| Sligo | — |
10 TOPS · FIRST 8
Hedtke-Anzaldua Unit42-255-36478
1.6 KM · Marathon Oil EF LLC · Section with this well →
| Yegua | 1,462 | -1,039 |
| Queen City | 3,563 | -3,140 |
| Reklaw | 4,147 | -3,724 |
| Carrizo | 4,500 | -4,077 |
| Wilcox | 6,104 | -5,681 |
| Austin Chalk | 11,188 | -10,765 |
| Eagle Ford | 11,391 | -10,968 |
| Sligo | — |
10 TOPS · FIRST 8
Creel Mixon-Hedtke Anzaldua Psa42-255-36479
1.7 KM · Marathon Oil EF LLC · Section with this well →
| Yegua | 1,462 | -1,038 |
| Queen City | 3,563 | -3,139 |
| Reklaw | 4,147 | -3,723 |
| Carrizo | 4,500 | -4,076 |
| Wilcox | 6,104 | -5,680 |
| Austin Chalk | 11,191 | -10,767 |
| Eagle Ford | 11,396 | -10,972 |
| Sligo | — |
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/25537509, documented in the API reference.