Increasing Drilling Efficiency and Reducing Risk by Actively Steering toward the Target with Seismic while Drilling Tech

Abstract

Summary In 2017, Eni drilled a deviated exploration well. The well presented challenges due to a complex subsurface with depth uncertainty and close proximity to a salt structure. This structural uncertainty created a risk that the target true location could be significantly different to the pre-drill prognosis. This case study describes how the operator helped to mitigate against this risk and map the position of the wellbore in the surface seismic cube by utilizing Seismic While Drilling (SWD) to acquire real-time (RT) seismic checkshot’s and up-going reflection measurements. The technology was successfully deployed over three hole sections to efficiently acquire the RT checkshot survey, a Zero Offset Vertical Seismic Profile (ZVSP), a RT Vertically Incident Vertical Seismic Profile (VIVSP) and an Offset Vertical Seismic Profile (OVSP) surveys without using any rig time.