ROCK PEN CLEARFORK UNIT

Oil · District 7C · Lease #13010

Operator: ST. MARY LAND & EXPLORATION CO.

Cum Oil

927k BBL

Cum Gas

14k MCF

casinghead

Wells

28

Production

1993-01 — 2021-03

Peak Month

1993-01

Production History

Cum Oil: 926,618 BBL Cum Gas: 13,714 MCF

RRC production reported through Apr 2026 · recent months incomplete

Decline Curve Analysis

qi

17,497 BBL/mo

Di (annual)

32.3%

b-factor

0.3

EUR

912,958 BBL

R-squared

0.965

type

hyperbolic

Operator History (from monthly production reports)

2000-06 — 2021-07 ARMOR PETROLEUM, INC. 254 mo
1997-07 — 2000-05 ST. MARY LAND & EXPLORATION CO. 35 mo
1996-07 — 1997-06 ST. MARY LAND & EXPL. CO. -CMC 12 mo
1993-01 — 1996-06 SIETE OIL AND GAS CORPORATION 42 mo

Wells (28)

WELL#APIOPERATORPERMITSDEPTHLAST_ISSUED
2230CORE PETRO, LLC23,7002008-03-13
2115CORE PETRO, LLC13,8001992-08-18
27CORE PETRO, LLC23,8001992-02-12
2224SIETE OIL AND GAS CORPORATION13,7001990-07-26
2225CORE PETRO, LLC13,7001990-06-21
2223SIETE OIL AND GAS CORPORATION23,9001989-07-24
2221CORE PETRO, LLC13,8501988-06-15
2112SIETE OIL AND GAS CORPORATION13,7001986-02-04
2220CORE PETRO, LLC13,6501985-12-02
2110SIETE OIL AND GAS CORPORATION13,6001985-11-19
2219SIETE OIL AND GAS CORPORATION13,9001985-02-11
2307SIETE OIL AND GAS CORPORATION13,8501985-01-03
2304SIETE OIL AND GAS CORPORATION13,8501984-11-19
2303SIETE OIL AND GAS CORPORATION13,9001984-11-16
2306SIETE OIL AND GAS CORPORATION14,0001984-11-16
2217CORE PETRO, LLC13,7501984-05-22
2216CORE PETRO, LLC13,8001984-04-24
1901ARMOR PETROLEUM, INC.27,2001984-04-03
2106CORE PETRO, LLC13,6001984-02-27
2214CORE PETRO, LLC13,8001984-01-30
2215SIETE OIL AND GAS CORPORATION13,7501983-12-14
2104CORE PETRO, LLC13,7001983-12-08
2103CORE PETRO, LLC13,8001983-10-18
2211CORE PETRO, LLC13,8001983-10-18
2212CORE PETRO, LLC13,8001983-10-18
2209CORE PETRO, LLC13,8001983-08-25
2207CORE PETRO, LLC13,7001983-03-09
2205CORE PETRO, LLC13,7001982-12-10