Simulation of Wells with Fishbones using ECLIPSE

Abstract

Fishbones is a new stimulation technology that aims to provide hydraulic fracturing like stimulation while also leaving the operator in full control of the stimulation process. The technology creates up to several hundred thin, 12 meter long laterals that extend orthogonally out from the wellbore. This increases the effective wellbore radius and improves well to reservoir communication. Three full scale tests of Fishbones have previously been conducted and found successful. This thesis considers fine scale simulation of a well with Fishbones in ECLIPSE. Two different ways of modeling the Fishbones laterals, as fractures and as laterals, are compared. Modeling the Fishbones laterals as fractures was found to give a more accurate solution than defining them as laterals, but with an increased run time. Several cases that investigated the effect of Fishbones in a well producing under steady state conditions were run. Fishbones was found to increase production by up to 60% compared to an unstimulated well, depending on spacing between the Fishbones laterals. The increase in production from a well with Fishbones also depend on the Fishbones lateral length. Doubling the Fishbones lateral length increased production rate by 80% compared to an unstimulated. Long needles with long spacing was found to give a higher increase in production compared to an unstimulated well than short needles with short spacing. Cases with Fishbones in a well that had severe damage in the near wellbore area showed that Fishbones was able to remove the effect of the damage and in some cases even increase the production above that of an unstimulated and undamaged well. Fishbones also increased production in formations with a low kv/kh compared to an unstimulated well. Fishbones was also capable of penetrating impermeable layers close to the well and improving communication throughout the reservoir. Upscaling using an apparent wellbore radius was also investigated. An apparent wellbore radius was found to be able to match the production rate and flowing bottom hole pressure (depending on well control) from a well with Fishbones in all flow conditions.