WELL · 42-255-33666 · DISTRICT 2
Challenger Unit A #10H
Karnes County · Eagleville (Eagle Ford-2) field · Producing · Horizontal
Challenger Unit A #10H (API 42-255-33666) is a horizontal well in Karnes County operated by Marathon Oil EF LLC, completed November 30, 2015 and listed as producing on the RRC schedule.
The RRC has issued one drilling permit, issued March 15, 2014, permitted to 18,000 ft.
Completion filings report 10 formation tops, including Yegua, Frio, Queen City, Reklaw.
Its lease has reported 2.93M barrels of oil and 4.38M mcf of gas since February 2012, last reporting in July 2026. The lease carries 11 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 LLCMar 15, 2014 |
- 18,000
- total depth, ft
- 1
- permits on file
- Mar 15, 2014
- last permit issued
- Nov 30, 2015
- completed
- 2.93M
- cumulative oil, bbl
- 4.38M
- cumulative gas, mcf
PRODUCTION FROM PDQ LEASE REPORTS · Feb 2012 THROUGH Jul 2026
Regulatory status · RRC wellbore file
- Schedule
- ON SCHEDULE
- Completed
- Nov 30, 2015
- Shut in
- —
- Plugged
- —
Operator's P-5 on the schedule: Active (A)
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 11 wells in total, so volumes are shared.Why →
| Lease | Field | Reporting operator | Wells | Oil, bbl | Gas, mcf | Reported |
|---|---|---|---|---|---|---|
| Challenger Unit A O-2-10519 | Eagleville (Eagle Ford-2) | Marathon Oil EF LLC | 11 | 2.93M | 4.38M | Feb 2012 – Jul 2026 |
Oil, barrels lease total
Last 12 months 33,350 · prior 12 59,017(-43%)
Gas, mcf lease total
Last 12 months 46,926 · prior 12 87,757(-47%)
Chain of custody
Every operator that reported production on this well's lease, in order.
- 1Marathon Oil EF LLCMay 2013 → Apr 2026
Permits
| Permit | Type | Operator | Received | Issued | Spud | Depth |
|---|---|---|---|---|---|---|
| 780218-99 | Drill | Marathon Oil EF LLC | Feb 19, 2014 | Mar 15, 2014 | Jun 7, 2014 | 18,000 |
Completions
| Completed | Lease | Field | Operator | Status | Depth |
|---|---|---|---|---|---|
| — | — O-2-10519 | — | — | — | — |
Formation tops
As filed on W-2/G-1. Subsea from 317 ft elevation.Download CSV →
| Formation | MD ft | Subsea |
|---|---|---|
| YeguaYEGUA - DISPOSAL | 1,089 | -772 |
| FrioFRIO - DISPOSAL | 3,200 | -2,883 |
| Queen City | 3,229 | -2,912 |
| Reklaw | 3,589 | -3,272 |
| Carrizo | 4,089 | -3,772 |
| WilcoxWILCOX - DISPOSAL | 4,789 | -4,472 |
| Anacacho | 10,429 | -10,112 |
| Austin ChalkAUSTIN CHALK - H2S | 10,547 | -10,230 |
| EdwardsEDWARDS - H2S | 10,630 | -10,313 |
| Eagle FordEAGLE FORD - H2S | 10,816 | -10,499 |
Perforations
Perforated and open-hole intervals.
| From | To | Type |
|---|---|---|
| 10,990 | 16,368 | Perforated |
Casing
Strings as reported, shallowest first.
| Casing in | Set at | Hole in | Cement |
|---|---|---|---|
| 9.625 | 5,282 | 12.25 | 1,680 S |
| 5.5 | 16,509 | 8.5 | 1,955 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 | Aug 25, 2016 | Aug 22, 2016 | Yes |
| 00 | Oct 9, 2014 | Jul 22, 2014 | 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 42-255-33666 → W-2, G-1, plugging reports, as PDFs
- Completion packets for 42-255-33666 → 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.
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/25533666, documented in the API reference.