WELL · 42-317-40784 · DISTRICT 8
Cox 12-9 Unit 1 #222
Martin County · Spraberry (Trend Area) field · Producing · Horizontal
Cox 12-9 Unit 1 #222 (API 42-317-40784) is a horizontal well in Martin County operated by Diamondback E&P LLC, completed January 19, 2023 and listed as producing on the RRC schedule.
The RRC has issued one drilling permit (amended once), issued March 28, 2017, permitted to 11,000 ft.
It was permitted by Endeavor Energy Resources L.P. and has since transferred to Diamondback E&P LLC on the wellbore schedule.
Completion filings report 10 formation tops, including Santa Rosa, Yates, Queen, Grayburg.
Its lease has reported 2.08M barrels of oil and 5.16M mcf of gas since August 2017, last reporting in July 2026. The lease carries 13 wells, so these are lease totals, not this well alone.
Operator of record
Permitted by Endeavor Energy Resources L.P.; the EWA schedule now lists a different operator.
Midland, TX · P-5 Y, filed Mar 4, 2026 · 5,231 permits on file · (855) 247-5920
SOURCE · RRC EWA WELLBORE SCHEDULE
What each RRC source says
| Wellbore schedule | Diamondback E&P LLC |
| Production reports | Diamondback E&P LLCthrough Apr 2026 |
| Latest permit | Endeavor Energy Resources L.P.Mar 28, 2017 |
The sources disagree, which usually means a transfer or a lease-level production filing by a different entity. Petrora goes with the schedule.
- 11,000
- total depth, ft
- 2
- permits on file
- Mar 28, 2017
- last permit issued
- Jan 19, 2023
- completed
- 2.08M
- cumulative oil, bbl
- 5.16M
- cumulative gas, mcf
PRODUCTION FROM PDQ LEASE REPORTS · Aug 2017 THROUGH Jul 2026
Regulatory status · RRC wellbore file
- Schedule
- ON SCHEDULE
- Completed
- Jan 19, 2023
- Shut in
- —
- Plugged
- —
Operator's P-5 on the schedule: X
Surface location
32.305274, -102.005548
OpenStreetMap → · Google Maps →
Permit surface location from the RRC GIS record, in Martin 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 13 wells in total, so volumes are shared.Why →
| Lease | Field | Reporting operator | Wells | Oil, bbl | Gas, mcf | Reported |
|---|---|---|---|---|---|---|
| Cox 12-9 Unit 1 O-10-49245 | Spraberry (Trend Area) | Diamondback E&P LLC | 13 | 2.08M | 5.16M | Aug 2017 – Jul 2026 |
Oil, barrels lease total
Last 12 months 498,220 · prior 12 818,801(-39%)
Gas, mcf lease total
Last 12 months 2,481,154 · prior 12 1,502,229(+65%)
Chain of custody
Every operator that reported production on this well's lease, in order.
- 1Endeavor Energy Resources L.P.Aug 2017 → Dec 2024
- 2Diamondback E&P LLCJan 2025 → Apr 2026
Permits
| Permit | Type | Operator | Received | Issued | Spud | Depth |
|---|---|---|---|---|---|---|
| 824811-98 | Drill | Endeavor Energy Resources L.P. | Apr 20, 2017 | Mar 28, 2017 | May 21, 2017 | 11,000 |
| 824811-99 | Drill | Endeavor Energy Resources L.P. | Mar 24, 2017 | Mar 28, 2017 | Apr 22, 2017 | 11,000 |
Completions
| Completed | Lease | Field | Operator | Status | Depth |
|---|---|---|---|---|---|
| — | — O-10-49245 | — | — | — | — |
Formation tops
As filed on W-2/G-1. Subsea from 2,834 ft elevation.Download CSV →
| Formation | MD ft | Subsea |
|---|---|---|
| Santa Rosa | 1,000 | 1,834 |
| Yates | 2,750 | 84 |
| Queen | 3,505 | -671 |
| Grayburg | 4,283 | -1,449 |
| San AndresSAN ANDRES - ACTIVE CO2 FLOOD; H | 4,350 | -1,516 |
| Cisco | 5,276 | -2,442 |
| Spraberry | 8,015 | -5,181 |
| Dean | 9,078 | -6,244 |
| Wolfcamp | 9,780 | -6,946 |
| Pennsylvanian | — | — |
Perforations
Perforated and open-hole intervals.
| From | To | Type |
|---|---|---|
| 10,130 | 17,751 | Perforated |
Casing
Strings as reported, shallowest first.
| Casing in | Set at | Hole in | Cement |
|---|---|---|---|
| 13.375 | 1,890 | 17.5 | 1,640 S |
| 9.625 | 9,046 | 12.25 | 1,365 S |
| 5.5 | 17,875 | 8.5 | 2,300 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 15, 2023 | Oct 2, 2023 | — |
| 00 | Feb 8, 2019 | Dec 14, 2018 | Yes |
| 00 | Jan 26, 2018 | Oct 25, 2017 | 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 42-317-40784 → W-2, G-1, plugging reports, as PDFs
- Completion packets for 42-317-40784 → scanned completion filings
Log images are in archives with no per-well link: the RRC's Neubus archive (2004 onward) and the University Lands library. 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.
Cox 12-9 Unit 142-317-45619
0.3 KM · Endeavor Energy Resources L.P. · Section with this well →
| Santa Rosa | 1,000 | 1,826 |
| Yates | 2,753 | 73 |
| Queen | 3,617 | -791 |
| Grayburg | 3,968 | -1,142 |
| San Andres | 4,725 | -1,899 |
| Clear Fork | 6,470 | -3,644 |
| Spraberry | 7,789 | -4,963 |
| Wolfcamp | — |
11 TOPS · FIRST 8
Cox 12-9 Unit 142-317-45620
0.3 KM · Endeavor Energy Resources L.P. · Section with this well →
| Santa Rosa | 1,000 | 1,826 |
| Yates | 2,755 | 71 |
| Queen | 3,620 | -794 |
| Grayburg | 3,973 | -1,147 |
| San Andres | 4,732 | -1,906 |
| Clear Fork | 6,472 | -3,646 |
| Spraberry | 7,791 | -4,965 |
| Wolfcamp | — |
11 TOPS · FIRST 8
Cox 12-9 Unit 142-317-45617
0.3 KM · Endeavor Energy Resources L.P. · Section with this well →
| Santa Rosa | 1,000 | 1,826 |
| Yates | 2,755 | 71 |
| Queen | 3,619 | -793 |
| Grayburg | 3,970 | -1,144 |
| San Andres | 4,731 | -1,905 |
| Spraberry | 7,791 | -4,965 |
| Precambrian (Undifferentiated) | — | |
| Cisco | — |
16 TOPS · FIRST 8
Cox 12-9 Unit 142-317-45616
0.3 KM · Endeavor Energy Resources L.P. · Section with this well →
| Santa Rosa | 1,000 | 1,826 |
| Yates | 2,755 | 71 |
| Queen | 3,620 | -794 |
| Grayburg | 3,792 | -966 |
| San Andres | 4,732 | -1,906 |
| Clear Fork | 6,481 | -3,655 |
| Spraberry | 7,805 | -4,979 |
| Dean | — |
11 TOPS · FIRST 8
Cox 12-9 Unit 142-317-45615
0.3 KM · Endeavor Energy Resources L.P. · Section with this well →
| Santa Rosa | 1,000 | 1,826 |
| Yates | 2,757 | 69 |
| Queen | 3,604 | -778 |
| Grayburg | 3,982 | -1,156 |
| San Andres | 4,733 | -1,907 |
| Spraberry | 7,779 | -4,953 |
| Wolfcamp | — | |
| Dean | — |
10 TOPS · FIRST 8
Cox 12-9 Unit 142-317-45618
0.3 KM · Endeavor Energy Resources L.P. · Section with this well →
| Santa Rosa | 1,000 | 1,826 |
| Yates | 2,754 | 72 |
| Queen | 3,620 | -794 |
| Grayburg | 3,972 | -1,146 |
| San Andres | 4,732 | -1,906 |
| Clear Fork | 6,472 | -3,646 |
| Spraberry | 7,794 | -4,968 |
| Cisco | — |
12 TOPS · FIRST 8
Cox 12-9 Unit 142-317-45621
0.3 KM · Endeavor Energy Resources L.P. · Section with this well →
| Santa Rosa | 1,000 | 1,827 |
| Yates | 2,757 | 70 |
| Queen | 3,623 | -796 |
| Grayburg | 3,977 | -1,150 |
| San Andres | 4,739 | -1,912 |
| Clear Fork | 6,476 | -3,649 |
| Spraberry | 7,793 | -4,966 |
| Devonian | — |
15 TOPS · FIRST 8
Cox 12-9 Unit 142-317-45622
0.3 KM · Endeavor Energy Resources L.P. · Section with this well →
| Santa Rosa | 1,000 | 1,827 |
| Yates | 2,756 | 71 |
| Queen | 3,622 | -795 |
| Grayburg | 3,975 | -1,148 |
| San Andres | 4,739 | -1,912 |
| Clear Fork | 6,477 | -3,650 |
| Spraberry | 7,806 | -4,979 |
| Cisco | — |
11 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/31740784, documented in the API reference.