HIERHOLZER RETZLOFF UNIT

Oil · District 01 · Lease #15621

Operator: MARATHON OIL EF LLC

Cum Oil

194k BBL

Cum Gas

215k MCF

casinghead

Wells

1

Production

2011-05 — 2025-12

Peak Month

2011-07

Production History

Cum Oil: 194,118 BBL Cum Gas: 214,727 MCF

RRC production reported through Apr 2026 · recent months incomplete

Decline Curve Analysis

qi

7,327 BBL/mo

Di (annual)

62.5%

b-factor

0.3

EUR

200,201 BBL

R-squared

0.781

type

hyperbolic

Operator History (from monthly production reports)

2011-11 — 2026-07 MARATHON OIL EF LLC 177 mo
2011-05 — 2011-10 HILCORP ENERGY COMPANY 6 mo

Wells (1)

WELL#APIOPERATORPERMITSDEPTHLAST_ISSUED
1HMARATHON OIL EF LLC113,5002011-02-17