42-255-35511

Final Completion Horizontal

KOWALIK 228-1R

KARNES County · District 2 · MARATHON OIL EF LLC · SUGARKANE (EAGLE FORD)

Permits

1

Max Depth

22,130 ft

First Permit

2017-06-21

Latest Activity

2017-06-21

Lifespan

< 1 yr

Regulatory Status

Schedule

OFF SCHEDULE

Completion

2018-10-22

Shut-In

Plugged

Production Summary

Cum Oil

bbl

Cum Gas

mcf

First Production

2014-09

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 (10) Elevation 419 ft (GR)

CSV
FormationTop Depth (MD)Subsea (+above / −below SL)
YEGUA - DISPOSAL (Yegua)1,826 ft-1,407 ft
QUEEN CITY 4,037 ft-3,618 ft
REKLAW 4,704 ft-4,285 ft
CARRIZO 4,999 ft-4,580 ft
WILCOX - DISPOSAL (Wilcox)6,461 ft-6,042 ft
AUSTIN CHALK - H2S (Austin Chalk)11,809 ft-11,390 ft
EAGLE FORD - H2S (Eagle Ford)11,907 ft-11,488 ft
EDWARDS - H2S (Edwards)
FRIO - DISPOSAL (Frio)
SLIGO - H2S (Sligo)

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
42-255-35510 KOWALIK 228-1R · MARATHON OIL EF LLC
0.0 mi
Yegua 1,802'Yegua 1,826'Queen City 3,948'Queen City 4,037'Reklaw 4,416'Reklaw 4,704'Carrizo 4,906'Carrizo 4,999'Wilcox 6,461'Austin Chalk 11,809'Austin Chalk 11,858'Eagle Ford 11,907' +5 more
42-255-35509 KOWALIK 228-1R · MARATHON OIL EF LLC
0.0 mi
Yegua 1,802'Queen City 3,948'Reklaw 4,416'Carrizo 4,906'Austin Chalk 11,838'Eagle Ford 11,935'Frio Sligo Wilcox Edwards
42-255-37729 CHILDREN WESTON-MOBIL A SA · MARATHON OIL EF LLC
0.2 mi
Queen City 3,784'Reklaw 4,247'Carrizo 4,920'Wilcox 4,992'Austin Chalk 11,747'Eagle Ford 11,870'Frio Yegua Sligo Edwards
42-255-37703 RANCHO GRANDE TRUST-KOWALIK SA · MARATHON OIL EF LLC
0.2 mi
Queen City 3,784'Reklaw 4,247'Carrizo 4,920'Wilcox 4,992'Austin Chalk 11,777'Eagle Ford 11,889'Yegua Frio Sligo Edwards
42-255-37017 DAVILA-WESTON HENKE UNIT SA C · MARATHON OIL EF LLC
0.2 mi
Yegua 1,667'Queen City 4,065'Reklaw 4,462'Carrizo 5,052'Wilcox 6,225'Austin Chalk 11,877'Eagle Ford 12,002'Frio Sligo Edwards
42-255-37016 DAVILA-WESTON HENKE UNIT SA B · MARATHON OIL EF LLC
0.2 mi
Yegua 1,667'Queen City 4,065'Reklaw 4,462'Carrizo 5,052'Wilcox 6,225'Austin Chalk 11,885'Eagle Ford 12,003'Sligo Frio Edwards
42-255-37015 DAVILA-WESTON HENKE UNIT SA A · MARATHON OIL EF LLC
0.2 mi
Yegua 1,667'Queen City 4,065'Reklaw 4,462'Carrizo 5,052'Wilcox 6,225'Austin Chalk 11,886'Eagle Ford 12,012'Frio Sligo Edwards
42-255-37018 DAVILA-MOBIL A-KENNEDY UNIT SA · MARATHON OIL EF LLC
0.2 mi
Yegua 1,667'Queen City 4,065'Reklaw 4,462'Carrizo 5,052'Wilcox 6,225'Austin Chalk 11,847'Eagle Ford 11,968'Frio Sligo Edwards

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
12,221–21,065 ftPerforated

Casing (2)

SizeSet DepthCement
9.625"6,060 ft1,950 sx
5.5"21,174 ft3,100 sx

Permit History (1)

Applications (1)

#827451 A MARATHON OIL EF LLC
received 2017-06-05

Records & Logs

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

W-2/G-1 2023-04-12 log on file
W-2/G-1 2018-11-07 log on file
W-2/G-1 2018-09-07 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 28.770315
Lon -98.011187

Well Details

Well Number
12H
Max Depth
22,130 ft
Drill Type
Horizontal
County
KARNES
District
2
Completed
2018-10-22

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