How geomechanics leads to safer and faster drilling operations

Abstract

Geomechanics is a discipline that is becoming increasingly relevant. When a new well is drilled, there is some uncertainty since there is not a lot of direct information of the local drilling conditions. The geomechanical study of the area and drilling history of the wells formerly drilled around this new emplacement improve the knowledge of the geomechanical problems that the driller can face. To be aware of the issues that happened in neighbor wells provides enough information for faster and safer drilling.

The defined workflows can be used for reducing the uncertainty in terms of drilling and defining the different stresses and strains among other geomechanical properties to define areas of compaction and subsidence.

The first approach to characterize a planned trajectory is to analyze and classify all the events that took place in previous drilling operations. Afterwards, 1D Geomechanical Models can be performed for the drilled and planned wells. Stability of the wellbore can be also analyzed to check which sections of a trajectory can be problematic. On the other hand, a trajectory can be better defined in order to avoid conflictive zones such as overpressured formations.

Apart from the 1D analysis, also 3D geomechanical models can be performed to define the in-situ stresses in the studied area as well as the generation of strains and the evolution of stresses during drilling operations. This kind of analyses through time is useful to optimize well trajectory and to study specific problems such as compaction and subsidence. In addition, the use of reliable constitutive models to represent the geomaterials behavior considering relevant features as anisotropy, elasto-plastic behavior, ductile/brittle response, dilatancy effects, among others, will allow to improve the stability analysis of the wellbore and optimize the well trajectory.

SUPRIMIR The objective of this paper is to present the importance of geomechanics and the advances on this field that is becoming more and more relevant.

AAPG Datapages/Search and Discovery Article #90192 © 2014 European Regional Conference and Exhibition, Barcelona, Spain, May 13-15, 2014