Geomechanics

Application of geomechanics technologies underpins Apache’s well delivery and production growth agenda.  Focus areas include drilling, completions and reservoir exploitation. 

In the drilling arena, Apache applies ‘best-in-industry’ software and know-how to help minimize problems of borehole instability, a recognized industry-wide problem contributing to drilling inefficiency and ‘non-productive time’.  Geomechanics specialists compile and analyze a wide range of subsurface data – from seismic, wire-line logs and previous drilling experiences – to evaluate the magnitude of stresses and pressures to be encountered along a planned well trajectory.  From this, the properties of the drilling fluids to be used in the well construction can be properly specified to both prevent uncontrolled releases of hydrocarbons (a ‘blowout’) from occurring and to maintain stability. 

Geomechanics technologies play an increasingly important integration role in the exploitation of Apache’s world-wide unconventional hydrocarbon resources – from shale gas reservoirs in Argentina and Canada to low permeability (tight) oil-bearing formations onshore U.S.  Horizontal well drilling and the implementation of multi-stage hydraulic fracturing stimulation technologies is revolutionizing the availability of hydrocarbons worldwide.  Horizontal wells are more challenging from a drilling and well construction standpoint than conventional vertical wells. Borehole stability considerations, therefore, are foremost among the technologies applied when planning wells of this kind.  Geomechanics specialists work closely with their subsurface and completions engineering counterparts in applying state-of-the-art methods to identify the most suitable locations to stimulate along the horizontal wellbore, and to assess the hydraulic pressures required to fracture the formation.  This integrated approach ensures the most cost-effective enhancements to hydrocarbon production are applied to a specific formation.

Geomechanics through the life of a field
 

Offshore, Apache’s geomechanics capabilities in sand-production prediction are being applied to evaluate the sanding risk in weakly-cemented reservoirs and to guide the selection of appropriate sand exclusion completion technologies, where needed.  Prediction methods have been developed in-house that incorporate the most up-to-date understanding of causal mechanisms.  Where tolerable sand production is expected – particularly later in the life of the well – active sand management strategies can be implemented to maintain oil production without the risk of severe sanding events from occurring. In this way, geomechanics technologies are being used to extend the productive life-span of Apache’s existing well-stock, and therefore maximizing the return on initial investment.

In deepwater, Apache’s geomechanics understanding and experience is amongst the industry’s best.  In above-salt developments (typically Pliocene and Miocene in age), reservoir rocks tend to be weak and deformable when hydrocarbons are produced.  In-depth understanding of rock compressibility is used to anticipate additional hydrocarbons that can be recovered from this additional reservoir drive energy.  Similarly, geomechanics capabilities are applied to the design of well components to resist the compaction that results from hydrocarbon production.  In sub-salt exploration and field development, advanced geomechanical understanding of the mechanical (creep) behavior of salt is applied to assure efficient well construction through the salt, as well as the long-term integrity of wells.  The high cost of drilling in deepwater requires close attention to detail.  Geomechanics technologies in the areas of pore pressure prediction, wellbore stability and reservoir appraisal are widely applied to help drive Apache’s expansion plans in this challenging environment.