WELL · 42-013-35261 · DISTRICT 1
Guajillo East #12H
Atascosa County · Eagleville (Eagle Ford-1) field · Injection · Horizontal
Guajillo East #12H (API 42-013-35261) is a horizontal well in Atascosa County operated by Marathon Oil EF LLC, completed June 21, 2021 and listed as injection on the RRC schedule.
The RRC has issued one drilling permit, issued December 12, 2014, permitted to 18,000 ft.
Completion filings report 11 formation tops, including Queen City, Reklaw, Bartosh, Carrizo.
Its lease has reported 10.9M barrels of oil and 14.6M mcf of gas since March 2014, last reporting in July 2026. The lease carries 61 wells, so these are lease totals, not this well alone.
Operator of record
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 schedule | Marathon Oil EF LLC |
| Production reports | Marathon Oil EF LLCthrough Apr 2026 |
| Latest permit | Marathon Oil EF LLCDec 12, 2014 |
- 18,000
- total depth, ft
- 1
- permits on file
- Dec 12, 2014
- last permit issued
- Jun 21, 2021
- completed
- 10.9M
- cumulative oil, bbl
- 14.6M
- cumulative gas, mcf
PRODUCTION FROM PDQ LEASE REPORTS · Mar 2014 THROUGH Jul 2026
Regulatory status · RRC wellbore file
- Schedule
- ON SCHEDULE
- Completed
- Jun 21, 2021
- Shut in
- —
- Plugged
- —
Operator's P-5 on the schedule: Active
Surface location
No coordinates on the permit record yet. The RRC's GIS record usually lands within days of issuance; historical master-file permits never carry one.
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 61 wells in total, so volumes are shared.Why →
| Lease | Field | Reporting operator | Wells | Oil, bbl | Gas, mcf | Reported |
|---|---|---|---|---|---|---|
| Guajillo East O-1-17741 | Eagleville (Eagle Ford-1) | Marathon Oil EF LLC | 61 | 10.9M | 14.6M | Mar 2014 – Jul 2026 |
Oil, barrels lease total
Last 12 months 192,543 · prior 12 317,175(-39%)
Gas, mcf lease total
Last 12 months 274,310 · prior 12 537,477(-49%)
Chain of custody
Every operator that reported production on this well's lease, in order.
- 1Marathon Oil EF LLCJun 2014 → Apr 2026
Permits
| Permit | Type | Operator | Received | Issued | Spud | Depth |
|---|---|---|---|---|---|---|
| 801681-99 | Drill | Marathon Oil EF LLC | Dec 12, 2014 | Dec 12, 2014 | Jul 3, 2015 | 18,000 |
Completions
| Completed | Lease | Field | Operator | Status | Depth |
|---|---|---|---|---|---|
| — | — O-1-17741 | — | — | — | — |
| — | — O-1-17741 | — | — | — | — |
Formation tops
As filed on W-2/G-1. Subsea from 304 ft elevation.Download CSV →
| Formation | MD ft | Subsea |
|---|---|---|
| Queen City | 2,915 | -2,611 |
| Reklaw | 3,277 | -2,973 |
| Bartosh | 3,676 | -3,372 |
| Carrizo | 3,917 | -3,613 |
| WilcoxWILCOX - DISPOSAL | 5,205 | -4,901 |
| EscondidoESCONDIDO - H2S, DISPOSAL | 7,620 | -7,316 |
| NavarroNAVARRO - H2S | 8,867 | -8,563 |
| OlmosOLMOS - DISPOSAL | 9,203 | -8,899 |
| AnacachoANACACHO - H2S | 10,654 | -10,350 |
| Austin ChalkAUSTIN CHALK - H2S, DISPOSAL | 10,888 | -10,584 |
| Eagle Ford | 11,027 | -10,723 |
Perforations
Perforated and open-hole intervals.
| From | To | Type |
|---|---|---|
| 11,893 | 16,297 | Perforated |
| 11,893 | 16,927 | Perforated |
Casing
Strings as reported, shallowest first.
| Casing in | Set at | Hole in | Cement |
|---|---|---|---|
| 9.625 | 5,277 | 12.25 | 1,745 S |
| 5.5 | 17,028 | 8.5 | 2,025 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 | Nov 13, 2024 | Oct 17, 2024 | — |
| 00 | May 26, 2023 | Dec 1, 2022 | — |
| 00 | Jun 24, 2016 | Dec 17, 2015 | 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 42-013-35261 → W-2, G-1, plugging reports, as PDFs
- Completion packets for 42-013-35261 → 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.
Beyond the permit record
RRC UIC permits · H-10 reported volumes
Injection
- 0
- bbl, last 12 reported months
- 0
- bbl, all reported
- Mar 2025
- reported through
| UIC | Kind | Status | Permitted bbl/d | Max psi | Zone ft |
|---|---|---|---|---|---|
| 000124734 | H-1 Injection | Canceled Sep 9, 2025 | 0 | 0 | 10,632–11,305 |
| 000126308 | H-1 Injection | Canceled Dec 12, 2023 | 0 | 0 | 10,632–11,305 |
MONTHLY INJECTED, BBL · H-10 · LAST 24 REPORTED MONTHS
Last 12 months 0 · prior 12 0
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/01335261, documented in the API reference.