COALBED METHANE PRODUCTION USING SHORT TO MEDIUM RADIUS HORIZONTAL WELLS

THE OBJECTIVE OF THIS PROJECT IS TO ADVANCE AN INNOVATIVE METHOD FOR COMMERCIALLY PRODUCING COALBED METHANE (CBM). CBM IS TYPICALLY PRODUCED USING CONVENTIONAL VERTICAL WELLS THAT HAVE BEEN HYDRAULICALLY STIMULATED TO ENHANCE THE FORMATION PERMEABILITY. THIS DOES NOT ALLOW FOR EFFICIENT REMOVAL OF THE TOTAL RESOURCE UNLESS DRILLING IS ACCOMPLISHED ON A CLOSE SPACING, WHICH ADVERSELY AFFECTS ECONOMICS. HORIZONTAL DRILLING FROM VERTICAL WELLS WILL PROVIDE THE BENEFIT OF ACCESS TO A LARGE PART OF THE COAL SEAM FROM A SINGLE WELL. IT WILL ALSO ALLOW ORIENTATION OF THE WELL TO ACHIEVE MAXIMUM GAS PRODUCTION. WITH THE EXISTING NATURAL FRACTURES IN COAL (CLEATS), HYDRAULIC FRACTURING FROM VERTICAL WELLS PROPAGATES PARALLEL TO THE PRIMARY FACE CLEATS. HORIZONTAL WELLS CAN BE ORIENTED PERPENDICULAR TO THE FACE CLEATS, LEADING TO MAXIMUM BENEFITFROM EXISTING FRACTURES. THE RESEARCH IN THIS PROJECT WILL ANSWER QUESTIONS REGARDING THE APPLICATION OF THIS DRILLING TECHNOLOGY TO CBM AND OTHER FRACTURED RESERVOIR PRODUCTION, INCLUDING THE TYPES OF DRILLING MUDS TO MAXIMIZE CBM PRODUCTION, THE TYPES OF DEWATERING TECHNIQUES TO BE USED, AND WHETHER THE ECONOMICS WILL JUSTIFY THE COST. THE RESEARCH WILL BE CARRIED OUT AT THE BIG RUN FIELD, WETZEL COUNTY, WV, BY REVITALIZING THIS FIELD, WHICH HAS PRODUCED OVER 2 BCF OF GAS FROM COALBEDS AT A DEPTH OF LESS THAN 1000 FEET. THE EXISTING WELLS HAVE DECLINED TO THE POINT WHERE THEY AVERAGE LESS THAN 1 MCFD PER WELL. THE RESULTS CAN ALSO BE TRANSPOSED TO OTHER SITES WHERE CBM PRODUCTION IS DECLINING, OR TO TOTALLY NEW SITES.