Integration of Pore Pressure/Fracture Gradient Prediction Methods and Real-Time Annulus Pressure Measurements Optimizes Drilling in Deltaic Environments

2007 ◽  
Author(s):  
Jeremy A. Greenwood ◽  
Mohamed Abdallah
Keyword(s):  
Real Time ◽  
Pore Pressure ◽  
Prediction Methods ◽  
Pressure Measurements ◽  
Fracture Gradient

Real-Time Pore Pressure and Fracture Gradient Evaluation in All Sedimentary Lithologies

1995 ◽  
Vol 10 (04) ◽  
pp. 215-222 ◽  
Author(s):  
P.W. Holbrook ◽  
D.A. Maggiori ◽  
Rodney Hensley
Keyword(s):  
Real Time ◽  
Pore Pressure ◽  
Fracture Gradient

Realtime Drilling Geomechanics Service, Case Study, Offshore Malaysia

2015 ◽  
Author(s):  
Babak Heidari ◽  
Sook Ting Leong ◽  
Nguyen Truong Son ◽  
M Zafril Aznor
Keyword(s):  
Real Time ◽  
Pore Pressure ◽  
Main Concern ◽  
Drilling Performance ◽  
Weight Window ◽  
Advance Notice ◽  
Complex Structural ◽  
Well Data ◽  
Fracture Gradient ◽  
Real Time Information

Abstract Real Time Drilling Geomechanics (RTDG) provides relevant real time information and integrated workflow to help clients in reducing operational risk and nonproductive time (NPT) through drilling in marginal economical and technically challenging environments. Dulang-B field is a technical challenge due to its complex structural geological environment. All the existing wells failed to penetrate into deep reservoir F40 sands due to wellbore instabilities issues. Overpressure in F-sands remains always the main concern and challenge which led to unsafe drilling environment and significant nonproductive time in the field. Avoiding drilling surprises means more than being prepared for problems when they occur; it means averting them in the first place. Appropriate safe mud weight to drill each formation, must be defined to overcome different overpressure zones and identify the best position for casing seat of each hole section of the well. With the knowledge acquired through pore pressure and fracture gradient modeling, well behavior could be foretold with enough advance notice to allow drilling team to calmly make technically sound operational decisions that lead to optimal drilling performance. This study presents the challenges and the main results of the collaborative drilling approach via RTDG (Real Time Drilling Geomechanics) operation in well DL-B28 ST2. This study focuses on the overpressure and narrow safe mud weight window as well as level of uncertainty over prognosis formation tops which has to be managed by integrating LWD seismicVISION* and RTDG which had clear impacts on decision making process. The real time measurement approach by utilizing actual well data provided the best solution to accurately constrain pre-drill pore pressure and fracture gradient model.

Real Time Integration of ECD, Temperature, Well Stability and Geo/Pore Pressure Simulations during drilling a challenging HPHT well

2010 ◽  
Author(s):  
Rolv Rommetveit ◽  
Knut Steinar Bjorkevoll ◽  
Pierre Rolf Cerasi ◽  
Stein Tjelta Havardstein ◽  
Mikkel Fjeldheim ◽  
...  
Keyword(s):  
Real Time ◽  
Pore Pressure ◽  
Time Integration

Overcoming Hole Instability in Highly Deviated Wells in the Kafr El Sheikh Shale, Offshore Mediterranean, Egypt

2021 ◽  
Author(s):  
Yasser Kholaif ◽  
Mahmoud Elmaghraby ◽  
Annick Nago ◽  
Jean-Michel Embry ◽  
Pramit Basu ◽  
...  
Keyword(s):  
Risk Assessment ◽  
Lower Bound ◽  
Real Time ◽  
Pore Pressure ◽  
Nile Delta ◽  
Stress Sensitivity ◽  
Rock Properties ◽  
Well Drilling ◽  
Geomechanical Monitoring ◽  
Deviated Wells

Abstract Drilling challenges in offshore Nile Delta have been largely documented in the literature. Operators are often confronted with drilling problems related to shale swelling, cavings, tight holes in combination with increased risks of lost circulation in some of the highly depleted formations. The Kafr El Sheikh shale in particular, has been linked to many instances of wellbore instability, due to its mineralogical composition (estimated to be mostly smectite, >70%). From offset well drilling experience, it could also be noticed that insufficient mud weight was often used to drill through the Kafr El Sheikh Shale, causing wellbore failure in shear due to lack of support of the wellbore wall. In the past, multiple mud weight designs have been implemented relying solely on pore pressure as lower bound of the mud window. With the increased use of geomechanics, it has been demonstrated that the lower bound should be taken as the maximum of the pore pressure and borehole collapse pressure, thus accounting for the effects of formation pressure, horizontal and vertical stresses, rock properties as well as wellbore trajectory. It has been proven that slight overpressure is often encountered halfway through the Kafr El Sheikh formation, which would typically result in slightly higher borehole collapse pressures. In the study fields, the operator expressed interest in drilling highly deviated wells (> 60-70 degrees). This raised concerns for increased drilling challenges, especially in the Kafr El Sheikh. A comprehensive and systematic risk assessment, design of a fit-for-purpose solution and its implementation during drilling took place in the fields of interest. Offset well data analytics from the subject fields supported a holistic evaluation of drilling risks associated with the Kafr El Sheikh, providing good understanding of stress sensitivity on deviation, azimuth and lithology. Upon building a robust geomechanical model, calibrated against offset well drilling experience, pre-drill mud weight and drilling practices recommendations were provided to optimize the drilling program. Near real-time geomechanical monitoring was implemented which helped to manage the model uncertainties. The implementation of a holistic risk assessment, including geomechanical recommendations and near real-time geomechanical monitoring, was effective to lead the drilling campaign successfully. As a result, three high angle wells (> 60-70 degrees) were drilled through the challenging Kafr El Sheikh formation without any hole instability. An integrated risk assessment of hole instability, managed in stages (pre-drill and during drilling), has helped to understand and simulate the behaviors of the formation. Proactive decisions have established a controlled drilling environment for successful operations.

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