Society of Petroleum Engineers
Distinguished Lecturer 2018-19 Lecture Season
The Unfulfilled Expectation of Horizontal Wells with Multistage Fracture Completions in Conventional Reservoirs: A Solution
Krešo Kurt Butulo
Schlumberger
Abstract:
This lecture presents approaches for increasing production from horizontal wells with multistage fracture (HWMSF) completions in conventional reservoirs. HWMSF completions are now regularly being drilled and completed in low-to-mid- permeability oil-bearing conventional reservoirs (k<10 md) where the oilfield is under water flooding. Although the industry has closed the HWMSF technology gap of drilling and completing these wells, the productivity has been below the expected level. The production is characterized by either an early-time relatively high production rate followed by a steep production decline and water breakthrough or low initial production and even lower late-time production. What went wrong and what can be done? The lessons learned in unconventional reservoirs are not pertinent to conventional formations. Hence, the problem was examined from the reservoir standpoint, focusing on achieving adequate pressure support to maximize drain-age, revising the water flood process through drilling patterns, and evaluating the specific completion techniques. Equally, the question warrants answers on current HWMSF re-stimulation, addressing methodology applied to specific completion design, the horizontal wellbore azimuthal orientation within the stress field, and, finally, the operating condition of the injector and producer wells. The lecture discusses novel designs for refracturing and for future reservoir development, and, at the same time, is a plea to the drilling, completion, and reservoir engineering teams to integrate their competencies to optimize these complex production systems.
Biography:
Krešo Kurt Butula holds the position of Reservoir Management Advisor to the Schlumberger President for Russia and Cen-tral Asia. He has a Masters degree in petro-leum engineering, University of Zagreb, Croatia, and has been based in Moscow, Russia, for the last 15 years. He has more than 27 years of worldwide onshore and offshore exposure and experience in multiple oilfield service domains. Currently, he is responsible for the assessments and integration process for complex subsurface projects and for defining the company business model and technological solutions, including new directions in Schlumberger R&E centers in Russia. Krešo Kurt has published a series of several technical papers for SPE and Rus-sian journals, received the Schlumberger Well Services R&D Input Award, and holds several patents related to hydraulic fracturing stimulation and IOR/EOR. He is a member of SPE and EAGE and a member of the Society of Core Analysts. He has been on program committees of international and Russian tech-nical conferences. He served as the Program Director for the Moscow SPE Section and was awarded the Regional Service Award in 2014. Since 2014, he has been the SPE Moscow Section Chairperson. He is a fluent speaker of Russian, English, German, Italian, and Croatian.