A drilling technology guided by well-seismic information integration

Abstract

The predictions by drilling-related mechanical and geological models are in some degree inaccurate due to non-unique solution of seismic velocity model. To address this problem, a new drilling technology guided by well-seismic information integration is proposed which consists of seismic velocity update of drilled formations, seismic velocity prediction of the formation ahead of drilling bit, and the prediction of geological feature and drilling geological environmental factors ahead of bit. In this technology, real information (velocity, formation and depth) behind the drilling bit and local pre-stack seismic data around the wellbore being drilled are used to correct the primitive seismic velocity field for a re-migration of seismic data and to update geological features and drilling geological environmental factors ahead of the drilling bit. Field application shows that this technology can describe and predict the geological features, drilling geological environmental factors and complex drilling problems ahead of the bit timely and improve the prediction efficiency and accuracy greatly. These new updated results are able to provide scientific basis for optimizing drilling decisions.

Keywords

• formation ahead of bit
• seismic velocity model
• geological feature
• drilling geological environmental factor
• real time prediction
• drilling decision optimization