This account describes how advanced well placement technology helped to optimize horizontal well position and maximize hydrocarbon production in deep water turbidite reservoirs. The deep reading directional electromagnetic tool, a latest-generation LWD (Logging While Drilling) measurement, was the technology differentiator for optimizing well placement in a number of deep water horizontal wells.
The new directional measurement is highly sensitive to reservoir boundaries and therefore gives early warning of conditions requiring steering adjustments while drilling horizontal wells, maximizing well position in the reservoir. This paper shows how thin oil rims, faulted reservoirs and those with highly variable structure were able to be developed more efficiently. By reducing uncertainties about the reservoir, the new technology helped optimize production, eliminate sidetracks and minimize well construction cost and risk.
One of the main challenges of maintaining a horizontal wellbore inside a thin hydrocarbon bed is the uncertainty of formation dip. Inside a hydrocarbon bed, real time resistivity images often yield dips that are more representative of stratigraphic features rather than structure defining reservoir boundaries (from surrounding, conductive shale beds). The deep-reading azimuthal electromagnetic measurement helped in early detection of neighboring conductive beds, and the distance to these beds. This ensured that the wellbore was drilled parallel to the structure and inside the ‘sweet spot’ away from non-productive layers.
As reservoirs become more challenging to develop, the use of advanced technology often helps minimize risk. When fields are developed with horizontal wells, it is desirable to maximize well position inside the reservoir layer since the rate of increase in hydrocarbon production increases as horizontal length in the reservoir increases. We show an example of how advanced well placement technology was successful in doubling hydrocarbon production rate compared with wells in the same field drilled with conventional technology.