HIERHOLZER UNIT

Oil · District 01 · Lease #15669

Operator: MARATHON OIL EF LLC

Cum Oil

135k BBL

Cum Gas

104k MCF

casinghead

Wells

1

Production

2010-12 — 2026-03

Peak Month

2010-12

Production History

Cum Oil: 134,524 BBL Cum Gas: 104,063 MCF

RRC production reported through Apr 2026 · recent months incomplete

Decline Curve Analysis

qi

3,450 BBL/mo

Di (annual)

43.4%

b-factor

0.3

EUR

135,208 BBL

R-squared

0.785

type

hyperbolic

Operator History (from monthly production reports)

2010-12 — 2026-07 MARATHON OIL EF LLC 188 mo

Wells (1)

WELL#APIOPERATORPERMITSDEPTHLAST_ISSUED
1HMARATHON OIL EF LLC315,7862012-05-17