Real-time hydrocarbons sweet spot identification in shale formations while drilling horizontally using geo-mechanical and geophysical parameters

摘要

This work presents an innovative comprehensive approach to properly identify intervals with the most favourable potential and properties to produce hydrocarbons known as hydrocarbons 'sweet spots'. The approach is applied to horizontal wells in shale formations but not limited to this scenario. One of the singularities of this work rests on the proposal that rock properties are obtained from logging while drilling (LWD) techniques. This self-supported methodology is applied to characterise the reservoir from the stand points of geo-mechanics, geophysics, and geopressure. Rock and fluid properties measured along the horizontal section of the well while drilling served to generate a synthetic acoustic log. Changes in trends of geo-mechanical and geophysical properties such as brittleness and acoustic impedance are used as indicators of hydrocarbons presence. Ultimately, the methodology is proposed to properly select the intervals to complete and to optimise the length of the horizontal section of the well. [Received: March 23, 2017; Accepted: September 5, 2018]