How can you use rock mechanics to improve drilling safety and efficiency?

Although safe and efficient drilling operation is needed, let's not forget the reason to drill. Optimal drilling parameter means better chance to maintain the quality/producability of targeted reservoir. The idea of an optimal drilling parameter is the balance between driller objectives vs the geoscientist objectives, and rock mechanics help in achieving those.

The Oil & Gas industry is presently massively under-sampling smaller-scale faults due to the scale gap between well and seismic data. This has resulted in a clear under-estimation of the effects that faults and fracture networks have on drilling operations, and actually explains why drilling problems often can appear random and uncorrelated with lithology. When applying High-resolution Fault Processing (HR-FP) to seismic data, it becomes clear that wells ALWAYS penetrate many smaller-scale faults in both overburden and reservoir sections. These intersections are most times directly linked with drilling issues such as fluid losses, hydrocarbon shows, borehole stability issues, stuck pipe, well losses, gas kicks, sudden overpressures, etc.

In Addition one must integrate: Geological Analysis understanding: lithology, Stress Regime from well bore and regional data, Identify parasequences of no changing conditions, homogeneous stress zones, to optimiza casing designs and adapt with logging while drilling info for contingency.

An understanding of the earth's principal stresses is paramount to determine your operational window in which you can drill a well, specially, deep water well. The principal stresses will determine your fracture gradient which if you were to surpass it, you risk the integrity of the well.

While rock mechanic models are essential for drilling and also production, it is critical to integrate them with seismic observations. High-resolution Fault Processing (HR-FP) results have shown that many drilling problems are directly linked with the penetration of smaller-scale faults. HR-FP results allow to design wells to stay clear of faulted or fractured zones in either overburden or reservoir sections (drilling risk mitigation). A Geomechanical model allows to also predict which of the faults in the vicinity of a well path could be critically stressed and potentially open, resulting e.g. in fluid losses during drilling. My studies have shown that losses most times occur when drilling through the intersection location of two faults.

important to consider incorporating a shallow hazard high-resolution 3D seismic survey as an excellent addition to the optimization process, especially during the critical early stages of drilling.

Rock mechanics plays a pivotal role in leveraging drilling results by constructing a comprehensive geodynamic dataset derived from the drilling process. This dataset becomes an integral component seamlessly integrated into simulation models, thereby informing the strategic planning of reservoir life-term initiatives. This approach extends to the meticulous design and optimization of production and injection wells throughout the entirety of the development lifespan. By merging drilling-derived geodynamic insights with simulation modeling, practitioners can make informed decisions that contribute to the efficiency, longevity, and overall success of reservoir development projects.

Completely agree to all statements! Apart from safe and cost-effective drilling, geomechanical models are also critical for the understanding of flow in reservoirs. Faults and fractures oriented parallel or sub-parallel to the present-day stress direction can be critically stressed and preferentially open, and with this channel flow. It is best to verify this model with image log interpretations, to check if open fractures have a preferential orientation.

It’s quite important to have good knowledge about faults and fractures network and their distribution as well as their orientation and their participation radius . Induced fractures caused by drilling operation are important to identify as well. Borehole damage caused by drilling fluid and the depth of invaded zone necessary to quantify in order to better got right formation evaluation.