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 waterflooding. 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 drainage, revising the waterflood process through drilling patterns, and evaluating the specific completion techniques. Equally, the question warrants answers on current HWMSF restimulation, 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.
Krešo Kurt holds the position of Director of Schlumberger Moscow Research center in Russia, responsible for the research programs in digital core and materials, modeling at pore scale level, multiphase flow, rock thermal properties, machine learning and cloud applications.
Krešo Kurt has graduated petroleum engineering from the University of Zagreb, Croatia, and has been based in Moscow, Russia, for the last 17 years. He has more than 29 years of worldwide onshore and offshore exposure and experience in multiple oilfield service domains with Schlumberger.
In his previous role as Advisor to the Schlumberger president for the area, he was 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, with specific emphasis on horizontal well multistage refracturing in low- to mid-permeability conventional reservoirs under waterflood.
Krešo Kurt has published technical papers for SPE and Russian technical journals, received the Schlumberger Well Services R&D Input Award, and holds multiple patents related to hydraulic fracturing stimulation and IOR/EOR.
Krešo Kurt has been a member of SPE and EAGE for years and served on program committees of international and Russian technical conferences. From 2011 to 2014, he served as the Program Director for the SPE Moscow Section, for which he was awarded the Regional Service Award in 2014. From 2014-2018, he was the SPE Moscow Section Chairperson.