AADE FMG Meeting

Presenting – “Mud Requirements for Rock with Strength Anisotropy”

 

The talk will focus on experiences drilling through rock exhibiting strength anisotropy. Rock anisotropy is observed in many shales across the world associated with weak bedding laminations and leads to varying MW requirements based on angle relative to the bedding plane through them. In addition, most of these shales show high sensitivity to water content in the mud leading to chemical instability. The instability issues in such shale are many times attributed to invasion of the drilling fluids into micro-fractures along bedding planes leading to suggestion of reducing MW. It has been observed multiple times that this is incorrect hypothesis and raising the MW based on borehole hoop stresses and anisotropic well formation while monitoring mud rheology and water activity will stabilize the wellbore.

 

Shekhar V. Gosavi completed his Ph.D. in Mechanical Engineering from Kansas State University in 2006 and started his career with ExxonMobil at Upstream Research Company. In various roles in last 18 years at ExxonMobil, he has contributed in areas of borehole management, fracturing/stimulation, injection, hydraulics, hole cleaning, integrity testing and other geomechanics aspects towards drilling and completions applications. Currently, as Principal Borehole Management Engineer, Shekhar is responsible for all aspects of Borehole Management area to provide operational guidance and support to all the business units as well as mentoring, training, and providing strategic & technological advancements for ExxonMobil. 

 

Presenting – “Wellbore Geomechanics: Drilling Fluids Aspects”

 

Wellbore geomechanics understanding is essential to prevent issues like rock collapse or fracture and consequences to wellbore stability such as pack off and mud losses. We review what are the key aspects related to drilling fluids and their impact on wellbore stability. Mud Weight helps to manage the geological component of wellbore stability by promoting a delicate balance between the wellbore radial pressure and circumferential rock stresses. Some failure mechanisms are revealed with a thorough analysis of drilling events, such as weak plane failure, delayed failure, and more. Finally, physicochemical interactions such as ionic diffusion and hydraulic diffusion can affect pore fluid pressure. In summary, understanding these drilling fluid aspects and rock failure aspects together is essential for maintaining stable wellbores during drilling operations.

 

Dr. Claudia Bonin is a Technology Principal at Halliburton, based in Houston. Dr Bonin’s expertise lies in Geomechanics Technology. Her role involves understanding rock behavior, wellbore stability, and mitigating risks during drilling. She worked as a global manager in Geomechanics for Halliburton Consulting from 2009 to 2018. Dr Bonin is also current chair of the SPE Geomechanics Technical Section. Before joining Halliburton, Dr Bonin worked as a Post-Doctoral Researcher in the Department of Mechanics and Materials Science at Rice University. She holds a bachelor’s degree in civil engineering and a PhD in Structural Engineering from the University of Campinas. 

 

 

Presenting – “Utilizing Geomechanics for Designing Wellbore Strengthening Material in the Mexican Onshore Projects”

 

Ixachi is an onshore Mexican gas field that presents severe wellbore stability issues while drilling through the Superior Eocene to the Paleocene. The lithology in these formations includes conglomerates, shales, and sandstones. The drilling problems reported include tight holes and hole enlargements, pack-offs, high torques and drags, shale swelling, excessive cavings (both angular and block cavings), partial and total fluid losses. The purpose of this presentation is to show how the geomechanical model was used to mitigate drilling risks, prevent fluid losses, and increase well performance by optimizing the mud window, casing depth and for drilling fluid additive selection.  The effectiveness of the fluid selection was verified by executing the PPT tests and the geomechanical fracture width model was used for designing wellbore strengthening material, anti-losses, and bridging materials.

 

Claudio Rabe is a Geomechanics Advisor with 20 years of international experience in consulting in pore pressure and fracturing gradient modelling (1D and 3D), wellbore stability, sand production, rock-fluid interaction, salt creep analysis, fault leaking, source rock quality evaluation, cap rock integrity, hydraulic fracturing (conventional and unconventional), and geomechanics for CCUS, gas storage and geothermal projects.  Experience on field and laboratory data acquisition and interpretation, laboratory testing execution, pre and real time modelling, basin modelling, analytical and numerical modelling, research and development solutions in oil and gas and energy transition.