Zett A.,British Petroleum |
Webster M.,British Petroleum |
Noordermeer A.,British Petroleum |
Hockley M.,GE Oilfield Technology |
And 3 more authors.
Petrophysics | Year: 2012
As horizontal wells become increasingly common, the need to make measurements to optimize well health and manage the reservoir also increases. Production logging in horizontal wells with multiphase flow presents data acquisition challenges in the form of conveyance method and sensor selection. In this paper we present an approach to logging a horizontal well using new generation array sensors. The well was cased and perforated with high water cut and sand production. Logging while tractoring a combination of conventional (centralized) and array sensors provided a good quality data set that enabled successful identification and shut-off of sand and water. The use of a new impeller design in a mini-spinner array helped overcome the challenges sand production posed in the well. Smaller mini-spinner thresholds improved the velocity profile, allowing us to identify water recirculation at very low rates. An array resistance measurement provided an estimate of water holdup. Tool rotation proved an important benefit for array sensors run in this harsh environment. Tool rotation helped keep the sensors free from debris while the traditional centralised spinner showed an increased tendency for jamming when intersecting sand accumulations in casing troughs or restrictions along the well trajectory. In addition, the rotating array sensors provide good circumferential coverage in the well. A sand detection instrument was used in combination with the production logging string. The instrument is combinable with the production logging string and simultaneous data acquisition permits to integrate all sensors, allowing a robust interpretation of sand influx and water salinity. This paper focuses on the acquisition of new generation array data to help meet the well intervention objectives leading to a commercial and technically successful outcome. It identifies the strengths and gaps of current technology relative to existing challenges in horizontal wells and the need to move to array measurements. © 2012 Society of Petrophysicists and Well Log Analysts. All Rights Reserved.