TEXAS · WELLS · ATASCOSA COUNTY · GUAJILLO UNIT 8 SOUTH LEASE · API 42-013-35414 · DISTRICT 01
Guajillo Unit 8 South #1H
Atascosa County · Eagleville (Eagle Ford-1) field · Producing · Horizontal
Guajillo Unit 8 South #1H (API 42-013-35414) is a horizontal well in Atascosa County operated by Marathon Oil EF LLC, completed December 29, 2017 and listed as producing on the RRC schedule.
The RRC has issued one drilling permit (amended once), issued November 8, 2016, permitted to 11,477 ft.
Completion filings report 10 formation tops, including Queen City, Reklaw, Bartosh, Carrizo.
Its lease has reported 1.5M barrels of oil and 2.95M mcf of gas since December 2017, last reporting in July 2026. The lease carries 5 wells, so these are lease totals, not this well alone.
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 LLCNov 8, 2016 |
- 11,477
- total depth, ft
- 2
- permits on file
- Nov 8, 2016
- last permit issued
- Dec 29, 2017
- completed
- 1.5M
- cumulative oil, bbl
- 2.95M
- cumulative gas, mcf
PRODUCTION FROM PDQ LEASE REPORTS · Dec 2017 THROUGH Jul 2026
Regulatory status · RRC wellbore file
- Schedule
- ON SCHEDULE
- Completed
- Dec 29, 2017
- Shut in
- —
- Plugged
- —
Operator's P-5 on the schedule: Active – Extension (X)
Surface location
28.660069, -98.276489
Permit surface location from the RRC GIS record, in Atascosa 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 5 wells in total, so volumes are shared.Why →
| Lease | Field | Reporting operator | Wells | Oil, bbl | Gas, mcf | Reported |
|---|---|---|---|---|---|---|
| Guajillo Unit 8 South O-1-19278 | Eagleville (Eagle Ford-1) | Marathon Oil EF LLC | 5 | 1.5M | 2.95M | Dec 2017 – Jul 2026 |
Oil, barrels lease total
Last 12 months 24,487 · prior 12 35,656(-31%)
Gas, mcf lease total
Last 12 months 37,752 · prior 12 95,584(-61%)
Chain of custody
Every operator that reported production on this well's lease, in order.
- 1Marathon Oil EF LLCDec 2017 → Apr 2026
Permits
| Permit | Type | Operator | Received | Issued | Spud | Depth |
|---|---|---|---|---|---|---|
| 819798-98 | Drill | Marathon Oil EF LLC | Mar 16, 2018 | Nov 8, 2016 | Jun 12, 2017 | 18,500 |
| 819798-99 | Drill | Marathon Oil EF LLC | Oct 26, 2016 | Nov 8, 2016 | Jun 12, 2017 | 18,500 |
Completions
| Completed | Lease | Field | Operator | Status | Depth |
|---|---|---|---|---|---|
| Dec 29, 2017 | Guajillo Unit 8 South O-1-19278 | Eagleville (Eagle Ford-1) | Marathon Oil EF LLC | Producing | 11,477 |
Formation tops
As filed on W-2/G-1. Subsea from 249 ft elevation.Download CSV →
| Formation | MD ft | Subsea |
|---|---|---|
| Queen City | 3,035 | -2,786 |
| Reklaw | 3,396 | -3,147 |
| Bartosh | 3,795 | -3,546 |
| Carrizo | 4,036 | -3,787 |
| WilcoxWILCOX - DISPOSAL | 5,324 | -5,075 |
| NavarroNAVARRO - H2S | 8,987 | -8,738 |
| OlmosOLMOS - DISPOSAL | 9,323 | -9,074 |
| AnacachoANACACHO - H2S | 10,804 | -10,555 |
| Austin ChalkAUSTIN CHALK - H2S, DISPOSAL | 11,041 | -10,792 |
| EscondidoESCONDIDO - H2S, DISPOSAL | — | — |
Perforations
Perforated and open-hole intervals.
| From | To | Type |
|---|---|---|
| 11,610 | 17,787 | Perforated |
Casing
Strings as reported, shallowest first.
| Casing in | Set at | Hole in | Cement |
|---|---|---|---|
| 9.625 | 5,342 | 12.25 | 1,741 S |
| 5.5 | 17,897 | 8.5 | 3,177 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 21, 2018 | Feb 22, 2018 | 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 42-013-35414 → W-2, G-1, plugging reports, as PDFs
- Completion packets for 42-013-35414 → 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.
Guajillo Unit 8 South42-013-35413
0.0 KM · Marathon Oil EF LLC · Section with this well →
| Queen City | 3,035 | -2,785 |
| Reklaw | 3,396 | -3,146 |
| Bartosh | 3,795 | -3,545 |
| Carrizo | 4,036 | -3,786 |
| Wilcox | 5,324 | -5,074 |
| Navarro | 8,987 | -8,737 |
| Olmos | 9,323 | -9,073 |
| Anacacho | 10,789 | -10,539 |
10 TOPS · FIRST 8
Guajillo Unit 8 South42-013-35415
0.0 KM · Marathon Oil EF LLC · Section with this well →
| Queen City | 3,035 | -2,784 |
| Reklaw | 3,396 | -3,145 |
| Bartosh | 3,795 | -3,544 |
| Carrizo | 4,036 | -3,785 |
| Wilcox | 5,324 | -5,073 |
| Navarro | 8,987 | -8,736 |
| Olmos | 9,323 | -9,072 |
| Anacacho | 10,800 | -10,549 |
10 TOPS · FIRST 8
Guajillo Unit 8 South42-013-35416
0.0 KM · Marathon Oil EF LLC · Section with this well →
| Queen City | 3,035 | -2,784 |
| Reklaw | 3,396 | -3,145 |
| Bartosh | 3,795 | -3,544 |
| Carrizo | 4,036 | -3,785 |
| Wilcox | 5,324 | -5,073 |
| Navarro | 8,987 | -8,736 |
| Olmos | 9,323 | -9,072 |
| Anacacho | 10,792 | -10,541 |
10 TOPS · FIRST 8
Guajillo Unit 8 South42-013-35417
0.0 KM · Marathon Oil EF LLC · Section with this well →
| Queen City | 3,035 | -2,783 |
| Reklaw | 3,396 | -3,144 |
| Bartosh | 3,795 | -3,543 |
| Carrizo | 4,036 | -3,784 |
| Wilcox | 5,324 | -5,072 |
| Navarro | 8,987 | -8,735 |
| Olmos | 9,323 | -9,071 |
| Anacacho | 10,788 | -10,536 |
10 TOPS · FIRST 8
Guajillo Unit 8 North42-013-35544
0.1 KM · Marathon Oil EF LLC · Section with this well →
| Queen City | 3,027 | -2,779 |
| Reklaw | 3,389 | -3,141 |
| Carrizo | 4,029 | -3,781 |
| Wilcox | 5,317 | -5,069 |
| Anacacho | 10,827 | -10,579 |
| Austin Chalk | 11,056 | -10,808 |
| Bartosh | — | |
| Navarro | — |
10 TOPS · FIRST 8
Guajillo Unit 8 North42-013-35545
0.1 KM · Marathon Oil EF LLC · Section with this well →
| Queen City | 3,027 | -2,778 |
| Reklaw | 3,389 | -3,140 |
| Carrizo | 4,029 | -3,780 |
| Wilcox | 5,317 | -5,068 |
| Anacacho | 10,825 | -10,576 |
| Austin Chalk | 11,053 | -10,804 |
| Navarro | — | |
| Olmos | — |
10 TOPS · FIRST 8
Guajillo Unit 8 North42-013-35546
0.1 KM · Marathon Oil EF LLC · Section with this well →
| Queen City | 3,027 | -2,777 |
| Reklaw | 3,389 | -3,139 |
| Carrizo | 4,029 | -3,779 |
| Wilcox | 5,317 | -5,067 |
| Anacacho | 10,820 | -10,570 |
| Austin Chalk | 11,052 | -10,802 |
| Bartosh | — | |
| Escondido | — |
10 TOPS · FIRST 8
Guajillo Unit 8 North42-013-35547
0.1 KM · Marathon Oil EF LLC · Section with this well →
| Queen City | 3,027 | -2,775 |
| Reklaw | 3,389 | -3,137 |
| Carrizo | 4,029 | -3,777 |
| Wilcox | 5,317 | -5,065 |
| Anacacho | 10,812 | -10,560 |
| Austin Chalk | 11,044 | -10,792 |
| Navarro | — | |
| Olmos | — |
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/01335414, documented in the API reference.