WELL · 42-013-36038 · DISTRICT 1
Hierholzer Seewald Retzloff SA4 #4H
Atascosa County · Eagleville (Eagle Ford-1) field · Producing · Horizontal
Hierholzer Seewald Retzloff Sa4 #4H (API 42-013-36038) is a horizontal well in Atascosa County operated by Marathon Oil EF LLC, completed May 22, 2024 and listed as producing on the RRC schedule.
The RRC has issued one drilling permit (amended once), issued June 30, 2023, permitted to 18,000 ft.
Completion filings report 11 formation tops, including Sparta, Queen City, Reklaw, Carrizo.
Its lease has reported 277K barrels of oil and 373K mcf of gas since August 2023, last reporting in July 2026.
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 LLCJun 30, 2023 |
- 18,000
- total depth, ft
- 2
- permits on file
- Jun 30, 2023
- last permit issued
- May 22, 2024
- completed
- 277K
- cumulative oil, bbl
- 373K
- cumulative gas, mcf
PRODUCTION FROM PDQ LEASE REPORTS · Aug 2023 THROUGH Jul 2026
Regulatory status · RRC wellbore file
- Schedule
- ON SCHEDULE
- Completed
- May 22, 2024
- Shut in
- —
- Plugged
- —
Operator's P-5 on the schedule: Active
Surface location
28.790681, -98.115644
OpenStreetMap → · Google Maps →
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; this well is the only one on it.Why →
| Lease | Field | Reporting operator | Wells | Oil, bbl | Gas, mcf | Reported |
|---|---|---|---|---|---|---|
| Hierholzer Seewald Retzloff SA4 O-1-21182 | Eagleville (Eagle Ford-1) | Marathon Oil EF LLC | 1 | 277K | 373K | Aug 2023 – Jul 2026 |
Oil, barrels lease total
Last 12 months 78,750 · prior 12 138,851(-43%)
Gas, mcf lease total
Last 12 months 87,831 · prior 12 227,472(-61%)
Chain of custody
Every operator that reported production on this well's lease, in order.
- 1Marathon Oil EF LLCMar 2024 → Apr 2026
Permits
| Permit | Type | Operator | Received | Issued | Spud | Depth |
|---|---|---|---|---|---|---|
| 891496-98 | Drill | Marathon Oil EF LLC | Apr 9, 2024 | Jun 30, 2023 | Feb 13, 2024 | 14,000 |
| 891496-99 | Drill | Marathon Oil EF LLC | Jun 20, 2023 | Jun 30, 2023 | Jul 26, 2023 | 18,000 |
Completions
| Completed | Lease | Field | Operator | Status | Depth |
|---|---|---|---|---|---|
| — | — O-1-21182 | — | — | — | — |
Formation tops
As filed on W-2/G-1. Subsea from 397 ft elevation.Download CSV →
| Formation | MD ft | Subsea |
|---|---|---|
| Sparta | 2,964 | -2,567 |
| Queen City | 3,266 | -2,869 |
| Reklaw | 3,798 | -3,401 |
| Carrizo | 4,446 | -4,049 |
| WilcoxWILCOX - DISPOSAL | 4,505 | -4,108 |
| AnacachoANACACHO - H2S | 10,589 | -10,192 |
| Austin ChalkAUSTIN CHALK - H2S, DISPOSAL | 10,745 | -10,348 |
| Bartosh | — | — |
| EscondidoESCONDIDO - H2S, DISPOSAL | — | — |
| NavarroNAVARRO - H2S | — | — |
| OlmosOLMOS - DISPOSAL | — | — |
Perforations
Perforated and open-hole intervals.
| From | To | Type |
|---|---|---|
| 11,272 | 20,594 | Perforated |
Casing
Strings as reported, shallowest first.
| Casing in | Set at | Hole in | Cement |
|---|---|---|---|
| 9.625 | 5,260 | 12.25 | 1,295 S |
| 6 | 20,594 | 8.75 | 3,300 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 | Aug 14, 2024 | Aug 2, 2024 | — |
| 00 | May 6, 2024 | Mar 25, 2024 | — |
| 00 | Dec 20, 2023 | Nov 27, 2023 | 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 42-013-36038 → W-2, G-1, plugging reports, as PDFs
- Completion packets for 42-013-36038 → 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 neighbours, subsea-aligned so they line up regardless of surface terrain.
Hierholzer Seewald Retzloff SA342-013-36037
0.0 KM · Marathon Oil EF LLC · Section with this well →
| Sparta | 2,964 | -2,567 |
| Queen City | 3,266 | -2,869 |
| Reklaw | 3,798 | -3,401 |
| Carrizo | 4,446 | -4,049 |
| Wilcox | 4,504 | -4,107 |
| Anacacho | 10,586 | -10,189 |
| Austin Chalk | 10,735 | -10,338 |
| Escondido | — |
11 TOPS · FIRST 8
Hierholzer-Chapman SA42-013-36039
0.0 KM · Marathon Oil EF LLC · Section with this well →
| Queen City | 3,266 | -2,869 |
| Reklaw | 3,798 | -3,401 |
| Carrizo | 4,446 | -4,049 |
| Wilcox | 4,504 | -4,107 |
| Anacacho | 10,591 | -10,194 |
| Austin Chalk | 10,751 | -10,354 |
| Eagle Ford | 10,902 | -10,505 |
| Bartosh | — |
11 TOPS · FIRST 8
Kellner-Jonas Unit42-013-35807
0.6 KM · Marathon Oil EF LLC · Section with this well →
| Queen City | 2,913 | -2,482 |
| Reklaw | 3,684 | -3,253 |
| Carrizo | 4,188 | -3,757 |
| Wilcox | 4,527 | -4,096 |
| Anacacho | 10,613 | -10,182 |
| Austin Chalk | 10,763 | -10,332 |
| Navarro | — | |
| Olmos | — |
10 TOPS · FIRST 8
Kellner-Jonas Unit42-013-35808
0.6 KM · Marathon Oil EF LLC · Section with this well →
| Queen City | 2,913 | -2,482 |
| Reklaw | 3,684 | -3,253 |
| Carrizo | 4,188 | -3,757 |
| Wilcox | 4,527 | -4,096 |
| Anacacho | 10,618 | -10,187 |
| Austin Chalk | 10,764 | -10,333 |
| Olmos | — | |
| Bartosh | — |
12 TOPS · FIRST 8
Kellner-Jonas Unit42-013-35809
0.6 KM · Marathon Oil EF LLC · Section with this well →
| Queen City | 2,913 | -2,483 |
| Reklaw | 3,684 | -3,254 |
| Carrizo | 4,188 | -3,758 |
| Wilcox | 4,527 | -4,097 |
| Anacacho | 10,611 | -10,181 |
| Austin Chalk | 10,762 | -10,332 |
| Escondido | — | |
| Bartosh | — |
10 TOPS · FIRST 8
Kellner-Jonas Unit42-013-35810
0.6 KM · Marathon Oil EF LLC · Section with this well →
| Queen City | 2,913 | -2,482 |
| Reklaw | 3,684 | -3,253 |
| Wilcox | 4,188 | -3,757 |
| Anacacho | 10,328 | -9,897 |
| Austin Chalk | 10,767 | -10,336 |
| Olmos | — | |
| Navarro | — | |
| Escondido | — |
10 TOPS · FIRST 8
Chapman Rothe Unit42-013-35411
1.5 KM · Marathon Oil EF LLC · Section with this well →
| Queen City | 2,858 | -2,452 |
| Reklaw | 3,433 | -3,027 |
| Bartosh | 3,686 | -3,280 |
| Carrizo | 4,104 | -3,698 |
| Wilcox | 5,520 | -5,114 |
| Navarro | 8,670 | -8,264 |
| Olmos | 9,057 | -8,651 |
| Anacacho | 10,386 | -9,980 |
10 TOPS · FIRST 8
Stubby A42-013-36122
1.6 KM · Verdun Oil & Gas LLC · Section with this well →
| Anacacho | 10,732 | -10,363 |
| Austin Chalk | 10,861 | -10,492 |
| Wilcox | — | |
| Bartosh | — | |
| Carrizo | — | |
| Escondido | — | |
| 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/01336038, documented in the API reference.