U.S. DEPARTMENT OF ENERGY ADVANCED OIL RECOVERY PROGRAM CLASS II SHALLOW-SHELF CARBONATE RESERVOIRS DE-FC22-93BC14983

Recovery of Bypassed Oil in the Dundee Formation Using Horizontal Drains James R. Wood Department of Geology Michigan Technological University

TOW 1-3 HD1 WELL SITE CRONUS EXPL. SPUDDED SEPT. 25, 1995SPUDDED SEPT. 25, 1995 COMPLETED OCT. 18, 1995COMPLETED OCT. 18, 1995 DEPTH 3518’ MD (3185’TVD)DEPTH 3518’ MD (3185’TVD) FLOWING BBLS/DAYFLOWING BBLS/DAY NO WATER CUTNO WATER CUT

MICHIGAN PROJECT TECHNIQUES l Horizontal Drilling l Well Logging l Modern Reservoir Management l Compile Database of All Historical, Geologic, Engineering, Production Data l Correlate Historical Reservoir Management with Production Histories

LOCATION MAP CRYSTAL FIELD FIELD STUDY AREA l l PROJECT OBJECTIVES l l Evaluate the Potential for Additional Recovery of Hydrocarbons in Michigan l l Develop: l l Partnerships with Industry to Test New Technologies for Improving Hydrocarbon Recovery in Existing Fields l l Resource Center for Technology and Information Transfer

MICHIGAN PROJECT Central Basin Study Area MICHIGAN PROJECT Central Basin Study Area CLARE ISABELLA MECOSTA MISSAUKEE MONTCALM OSCEOLA Crystal Field Belly Achers Douglas Reynolds Cato Hardy Dam Fork Coldwater Sherman Broomfield Gilmore Isabella Leaton Rosebush Vernon Currie Wise Freeman-Redding Lake George Winterfield Sylvan Evart & Prosper South Prosper Cranberry Lake & Cranberry Lake East Skeels Cedar Cat Creek Riverside

CRYSTAL FIELD WELLS USED IN STUDY (231)

Regional Distribution of Reservoir Lithology in Dundee Limestone Dolomite + Anhydrite

MICHIGAN BASIN STRATIGRAPHIC COLUMN MAJOR PRODUCING HORIZONS TRAVERSE DUNDEE NIAGARAN TRENTON PDC

EW CROSS-SECTION ACROSS MICHIGAN BASIN THROUGH CRYSTAL FIELD

Reed City Anhydrite Thins and is Absent in Vicinity of Crystal Field Part of Crystal Field Structure is Thought To Be Due to Salt Dissolution

Rogers City Carbonate Thins in Vicinity Of Crystal Field

CRYSTAL FIELD LOCATION MAP MONTCALM COUNTY, MI CRYSTAL FIELD

CRYSTAL FIELD CHARACTERISTICS l 2000 Acre Anticlinal Structure in Central Michigan Basin l Combination Structure/Diagenetic Trap l Fractured, Vuggy Dolomite Reservoir Capped With Thin Limestone and/or Shale l Strong Water Drive Reservoir l Average Pay Thickness 12 Feet, Maximum of 40 Feet. l Initial High Production Rates up to 9000 Bbls/Day Resulted in Inverse Coning of Water

STRUCTURE CONTOUR TOP DUNDEE FM. CI – 2 FT. TOW 1-3 HD FROST 1-5 HAPPY HOLIDAY 6-3 CRYSTAL FIELD DEMONSTRATION WELLS

CRYSTAL FIELD STRUCTURE CONTOUR TOW 1-3 HD

CRYSTAL FIELD 3D STRUCTURE TOW 1-3 HD TOP DUNDEE SALT COLLAPSE ??

TOW 1-3 HD WELL PLAN 650 FT. 8 5/8” CASING KICKOFF POINT ORIGINAL OIL/WATER CONTACT 3215 FT. 5 ½ “ TUBING ACTUAL HORIZONTAL LENGTH 95 FT. BEYOND CASING 7 7/8” HOLE 10 5/8” HOLE 3175 FT FT FT. VERTICALWELL. 450 FT FT FT. DUNDEE FM. BELL SH. TRAVERSE LM. CORE

TOW 1-3 HD-1 CORE PHOTO

CRYSTAL FIELD TOP DOLOMITE

RELATIONSHIP BETWEEN DUNDEE LIMESTONE & DOLOMITE AT CRYSTAL FIELD DOLOMITE LIMESTONE

Dundee Reservoir Lithologic Types l Limestone - depositional fabrics l Grainstone shoal sand bodies l Fenestral peritidal packstones and wackestones l Stromatoporoid/coral boundstone patch reefs l Dolomite - burial diagenetic fabrics l Fractured, vuggy, hydrothermal dolomite l Sucrosic, laminated, dolomite with anhydrite

Limestone Reservoir Fabrics l Stromatoporoid-coral boundstone patch reef l Intraparticle and intergranular porosity l Fractures augment moderate to high porosity/permeability l Main reservoir in one field present in others

Hydrothermal Dolomite Cement l Piece of slabbed core from the Leonard Oil-Lee #1 - Dry hole with oil shows Northwest of Crystal Field l Abundant fractures and vugs filled with white ”Saddle” (hydrothermal) dolomite

Limestone Reservoir Fabrics l Fenestral Peritidal packstones and wackestones l Vertical and horizontal fenestrae l High permeability and porosity l Main zone in several large fields

Thin-Section Photomicrograph Dundee Reservoir Crystal Field

Dundee Reservoir Characteristics l Lithology - Limestone or Dolomite l Pore Characteristics - Matrix, Vugs, and Fractures l Stratigraphy - Rogers City, Dundee, Reed City “Facies” l Production History – Initial High Oil/Water Ratios, Initial High Production Rates

LESSONS LEARNED: EVALUATION KEYS FOR IMPROVED RECOVERY ATTEMPTS l Reservoir Characterization –Accurate Mapping (esp. Dundee Fm.) –Porosity and Permeability –Dolomite Diagenesis Crucial l Production History –Field Development History –Field Wide/Individual Well Production –Well Status/Plugging Record

WHAT SHOULD HAVE BEEN DONE: l Avoid drilling wells low on structure l Map dolomite carefully l Focus on “Attic” oil l Spread DOE funding over more opportunities in more fields

FUTURE PLANS: l Project is ended but: –Re-examine Crystal Field TOW well in light of subsequent attempts to copy its success to see why it succeeded –Map dolomite over central Michigan Basin –Develop model for dolomite diagenesis

l l 27 Additional Devonian Horizontal wells l l 20 Dundee, 2 Traverse Lime, 3 Richfield, and 2 Detroit River Wells completed l l Average production about 30 bbls oil/day l l Total annual production - 300,000 bbls l l Gross wellhead value ($17/bbl) - $5,000,000/year l l Royalty owners’ share - $630,000/year l l State severance taxes - $250,000/year l l Federal, State, and local income taxes - $1,650,000/year l l Capital investment cost (27 wells) - $10,000,000 Economic Summary: HORIZONTAL WELLS

l Demonstration Well Tow 1-3 Produced 50,000+ Bbls Oil in 18 Months - No Water l Detailed Characterization of 30 Similar Fields l Drilling and Completion of Horizontal Drain l State Approval of Waiver of Liability for Pre-Existing Pollution in Field - Hundreds of Fields Are Similar Candidates l Stimulation of Interest in Horizontal Drilling - ~20 Dundee Permits in ; 78 wells currently permitted or drilling by 1998 l Horizontal Drilling has expanded statewide in several other formations. l Numerous undergraduate (50+), Masters (32+) and Ph.D (3) Students entered industry as direct result of DOE projects (1993 – 2002) Project Summary: BENEFITS

CRONUS EXPL. - TOW 1-3 HD1 WELL SITE

Project Summary: ADDITIONAL HD WELLS AT CRYSTAL FIELD l l Tow 1-3 HD1, BOPD; 135,000+ BBLS l l Frost 5-3 HD, water/oil l l Happy Holiday Tree Farm 6-3 HD, water/oil

Project Summary: FRACTURES l Fractures are present in most Dundee Dolomite reservoirs, enhancing oil productivity, but also allowing for water transport l Fractures enhance permeability, especially vertically, porosity may be altered by diagenetic changes. l Fractures and diagenesis have relation to structures and fault systems in basement l Fractures have strong relationship to hydrothermal systems that also produce pervasive dolomitization and HTD mineral suites

l 2 HART AWARDS l BEST NEW TECHNOLOGY l BEST NEW WELL Project Summary: AWARDS

DELIVERABLES (actually delivered ) l DIGITAL DATA l WELL LOCATIONS (53,000+) l FORMATION TOPS (465,000) l PRODUCTION HISTORY (40 Fields) l FIELD HISTORY – 40 Fields l WIRELINE LOGS - 50 l CORE DATA – 60 ft. Tow 1-3 l STRUCTURE AND ISOPACH MAPS l PROJECT CD-ROM – 500+ COPIES

PROJECT TEAM l MICHIGAN TECH UNIVERSITY l JAMES WOOD - PROJECT DIRECTOR l JACKIE HUNTOON - BASIN MODELING l WAYNE PENNINGTON - LOG ANALYSIS l WESTERN MICHIGAN UNIVERSITY l WILLIAM HARRISON - RES. CHARACTERIZATION l TERRA ENERGY, LTD. l CRAIG TESTER - PETROLEUM ENGINEER l ERIC TAYLOR - PETROLEUM GEOLOGY

Recovery of Bypassed Oil in the Dundee Formation Using Horizontal Drains James R. Wood Department of Geology Michigan Technological University