42-013-36038

PRODUCING Horizontal

HIERHOLZER SEEWALD RETZLOFF SA4

ATASCOSA County · District 1 · MARATHON OIL EF LLC · EAGLEVILLE (EAGLE FORD-1)

Permits

2

Max Depth

18,000 ft

First Permit

2023-06-30

Latest Activity

2023-06-30

Lifespan

< 1 yr

Regulatory Status

Schedule

ON SCHEDULE

Completion

2024-05-22

Shut-In

Plugged

P-5 Org Status: Active

Production Summary

Cum Oil

bbl

Cum Gas

mcf

First Production

2023-08

Last Production

2026-07

Lease Production

Production is reported at the lease level. View production data, decline curves, and history on the lease page.

Formation Tops (11) Elevation 397 ft (GL)

CSV
FormationTop Depth (MD)Subsea (+above / −below SL)
SPARTA 2,964 ft-2,567 ft
QUEEN CITY 3,266 ft-2,869 ft
REKLAW 3,798 ft-3,401 ft
CARRIZO 4,446 ft-4,049 ft
WILCOX - DISPOSAL (Wilcox)4,505 ft-4,108 ft
ANACACHO - H2S (Anacacho)10,589 ft-10,192 ft
AUSTIN CHALK - H2S, DISPOSAL (Austin Chalk)10,745 ft-10,348 ft
BARTOSH
ESCONDIDO - H2S, DISPOSAL (Escondido)
NAVARRO - H2S (Navarro)
OLMOS - DISPOSAL (Olmos)

As reported by operators on W-2/G-1 completion filings (RRC wellbore records). Depths are measured depth; names appear as filed. Subsea = reported elevation − measured depth (negative = below sea level; vertical wellbores only). View filings & logs at RRC ↗

Offset Well Tops (nearest 8 wells with tops)

What nearby completed wells reported.

Cross-section
42-013-36037 HIERHOLZER SEEWALD RETZLOFF SA3 · MARATHON OIL EF LLC
0.0 mi
Sparta 2,964'Queen City 3,266'Reklaw 3,798'Carrizo 4,446'Wilcox 4,504'Anacacho 10,586'Austin Chalk 10,735'Reklaw Navarro Queen City Bartosh Escondido +1 more
42-013-36039 HIERHOLZER-CHAPMAN SA · MARATHON OIL EF LLC
0.0 mi
Queen City 3,266'Reklaw 3,798'Carrizo 4,446'Wilcox 4,504'Anacacho 10,591'Austin Chalk 10,751'Eagle Ford 10,902'Olmos Escondido Bartosh Navarro
42-013-35807 KELLNER-JONAS UNIT · MARATHON OIL EF LLC
0.4 mi
Queen City 2,913'Reklaw 3,684'Carrizo 4,188'Wilcox 4,527'Anacacho 10,613'Austin Chalk 10,763'Olmos Escondido Bartosh Navarro
42-013-35808 KELLNER-JONAS UNIT · MARATHON OIL EF LLC
0.4 mi
Queen City 2,913'Reklaw 3,684'Carrizo 4,188'Wilcox 4,527'Anacacho 10,618'Austin Chalk 10,764'Edwards Bartosh Escondido Olmos Navarro Georgetown
42-013-35809 KELLNER-JONAS UNIT · MARATHON OIL EF LLC
0.4 mi
Queen City 2,913'Reklaw 3,684'Carrizo 4,188'Wilcox 4,527'Anacacho 10,611'Austin Chalk 10,762'Olmos Bartosh Navarro Escondido
42-013-35810 KELLNER-JONAS UNIT · MARATHON OIL EF LLC
0.4 mi
Queen City 2,913'Reklaw 3,684'Wilcox 4,188'Anacacho 10,328'Anacacho 10,628'Austin Chalk 10,767'Carrizo Bartosh Navarro Olmos Escondido
42-013-35411 CHAPMAN ROTHE UNIT · MARATHON OIL EF LLC
0.9 mi
Queen City 2,858'Reklaw 3,433'Bartosh 3,686'Carrizo 4,104'Wilcox 5,520'Navarro 8,670'Olmos 9,057'Anacacho 10,386'Austin Chalk 10,524'Escondido
42-013-36122 STUBBY A · VERDUN OIL & GAS LLC
1.0 mi
Anacacho 10,732'Austin Chalk 10,861'Navarro Reklaw Bartosh Carrizo Escondido Wilcox Olmos Queen City

Nearest wells within 10 mi (surface locations). Click wells to select them, then open the cross-section to compare tops side by side (max 6 wells per section, including this one).

Perforations (1)

IntervalType
11,272–20,594 ftPerforated

Casing (2)

SizeSet DepthCement
9.625"5,260 ft1,295 sx
6"20,594 ft3,300 sx

Permit History (2)

Applications (2)

#891496 A MARATHON OIL EF LLC
received 2024-04-09
#891496 A MARATHON OIL EF LLC
received 2023-06-20

Records & Logs

3 completion filings on record · 1 with log images at RRC.

W-2/G-1 2024-08-02
W-2/G-1 2024-03-25
W-2/G-1 2023-11-27 log on file

Completion packets open directly (post-2011 filings include attached logs). Log images can't be deep-linked — clicking copies the API for you to paste.

Lat 28.790681
Lon -98.115644

Well Details

Well Number
4H
Max Depth
18,000 ft
Drill Type
Horizontal
County
ATASCOSA
District
1
Completed
2024-05-22

Operator

Location
HOUSTON
P-5 Status
Active (filed 2025-09-26)
Cum Oil (all leases)
409,189,156 bbl
Cum Gas (all leases)
1,029,735,602 mcf
Activities
CSGD/G, CSGD/P, G/PUR, GTHS/C, GTHS/G, GTHS/O, OPRS/G, OPRS/O
Total Permits
3,173