Technology Focus: Horizontal and Complex-Trajectory Wells (November 2010)

Abstract

Technology Focus In the late 1980s, I helped plan one of the first horizontal wells in the UK North Sea. One aspect I recall was trying to force well-planning software to form a sensible trajectory from the surface location to the geometrically defined horizontal targets. The software did not cooperate until we realized that we had to plan the well from the bottom up. We had to enter the toe and heel target locations first and then build the trajectory back to surface. I never had to do that before, but it worked. When asked to write this introduction, the significance of that experience became apparent. It was the first time I remember planning a well from the bottom up. As horizontal-drilling activity increased, so did focus on the reservoir to improve the payback from these “more expensive” wells. As confidence to deliver these wells grew and performance improved, consideration was given to more-complex trajectories to enhance reservoir performance further. Over the last 20 years, this focus on the reservoir has driven tremendous advances in drilling and completion technology. Initially, these technologies were applied in high-cost drilling locations, but now are relied upon to improve or even to enable productivity more widely. For example, in the Middle East, complex multilateral wells are commonly drilled by use of advanced technologies to improve reservoir performance. Another example is onshore North America. Since mid-2009, there are more rigs drilling horizontal wells in this area than any other type of well. Application of advanced technologies onshore North America has enabled production from otherwise stranded reserves in these unconventional reservoirs. It is difficult to imagine any capability over the last 20 years that has contributed more to sustaining affordable energy supply than widespread application of horizontal wells, and we should expect the level of complexity to grow as the energy supply tightens. Horizontal and Complex-Trajectory Wells additional reading available at OnePetro: www.onepetro.org IPTC 13066 • “Characterizing the Flow Units in Carbonates With Production Logging and Borehole Images: Developing a Workflow in Western Offshore India,” by Ram Avtar, ONGC India, et al. IPTC 13453 • “Utilizing Advanced Well-Placement Process To Develop Structurally Complex Areas in Maydan Mahzam Field (Offshore Qatar)” by A. Al-Ahmed, Qatar Petroleum, et al. SPE 132816 • “An Innovative, Low-Cost Approach to Deriving Stress Conditions To Maximize Reserves Recovery in Unconventional Reservoirs” by Jason Kneedy, Chesapeake Operating, et al.