OPPORTUNITIES FOR HORIZONTAL WELLS AND PROBLEMSIN PREDICTING THEIR PERFORMANCE

F.J. FAYERS S. ARBABI K. AZIZ

this article begins on the next page FFCANADIAN SPE/CIM/CANMET THIS IS A PREPRINT - SUBJECT TO cORRECTION PAPER NO. HWC94-57 A METHOD FOR COMPLETING HORIZONTAL WELLS BY Jim B. Surjaatmadja Halliburton Energy Services PUBLICATION RIGHTS RESERVED THIS PAPER IS TO BE PRESENTED AT THE CANADIAN SPE/CIM/(CANMET INTERNATIONAL CONFERENCE ON RECENT ADVANCES IN HORIZONTAL WELL APPLICATIONS, MARCH 20-23,1994, CALGARY, CANADA. DISCUSSION OF THIS PAPER IS INVITED. SUCH DISCUSSION MAY BE PRESENTED AT THE TECHNICAL MEETING AND WILL BE CONSIDERED FOR PUBLICATION IN SPE AND CIM JOURNALS IF FILEDIN WRITING WITH THE TECHNICAL PROGRAM CHAIRMAN PRIOR TO TFIE CONCLUSION OF THE MEETING. ABSTRACT A new approach to complete horizontal wells is proposed to make future stimulation work much more effective. Current well design formulations, largely influenced by vertical well technologies, do not tend themselves well to further stimulation. Treatment of wells that have been depleted to noneconomical levels may generate marginal production increases. The new method uses hydrajetting technology to enhance the ability to successfully stimulate a horizontal well. It uses ahydrajetting tool that is capable of creating fan- shaped slots in the formation behind the casing in order to direct _fracture initiation correctly. Only limited size slots are cut through the casing, thus maintaining its integrity. Using this new approach will result in more effective treatment of localized areas, and will drastically improve stimulation or damage-bypass treatments. Tortuosities of fracture paths are reduced if not eliminated. Patent applications have been filed on the subject matter contained in this paper. INTRODUCTION Horizontal wells have a large potentialto improve the oil production rates and ultimate recovery of many reservoirs. technology, especially with the advanced stages of drilling and completion technology in this area. In fact, it has been demonstrated that re-entering an existing vertical wellbore to drill a horizontal segment is economically feasible.""" When low cost is the overriding concern in completing a horizontal Nvell, openhole completions are generally selected if borehole stability is not a problem. Such completions, however, do not provide options for remedial actions in the future. In addition, this type ofcompletion does not allow effective means for abandoning the well, and may be costly to manage during the later stages of the life of the well. Slotted liner completions provide advantages over the openhole method by their relatively low cost, yet better protection against wellbore collapse. However, as in openhole c:ompletions, slotted liners provide very few options for remedial procedures. Cemented casing completions are the most expensive, but they provided, most options currently available in vertical wefl technology. Effective stimulations, isolation of zones, andother remedial actions are possible. Well abandonment can also be performed effectively. Although initially more costly, in in any situations cemented casing completions proved to be very cost effective throughout the life of the well.