Validation of a 3d geomechanical model in wildcat exploration: a case study

Several wellbore instability problems have been encountered during drilling a shale formation in an offshore field, leading to the collapse of the main borehole and resulting in several sidetracks. In this study, an integrated 1D & 3D Geomechanical model was built for the field in order to investigate the major factors that control the instability problems from a Geomechanical point of view and to design an optimum mud window for planned wells in the field. Effect of bedding on wellbore stability was the most important factor to explain the observed drilling events. Optimized well paths for planned wells were proposed based on results of a sensitivity analysis of the effect of bedding orientation on wellbore stability. It has been observed that bedding exposed depends not only on well inclination but also on dip of the formation, attack angle, and azimuth.

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Seismic Driven 3D Geomechanical Model of Lower Paleozoic Shale Formation (Eastern Europe) – Case Study

78th EAGE Conference and Exhibition 2016 ◽

10.3997/2214-4609.201601443 ◽

2016 ◽

Cited By ~ 1

Author(s):

M. Słota-Valim ◽

K. Sowiżdżał ◽

H.B. Jedrzejowska-Tyczkowska

Keyword(s):

Eastern Europe ◽

Geomechanical Model ◽

Lower Paleozoic ◽

3D Geomechanical Model ◽

Shale Formation

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Impact of High Resolution 3D Geomechanics on Well Optimization in the Southern Gulf of Suez, Egypt

10.2118/206271-ms ◽

2021 ◽

Author(s):

Mohamed Elkhawaga ◽

Wael A. Elghaney ◽

Rajarajan Naidu ◽

Assef Hussen ◽

Ramy Rafaat ◽

...

Keyword(s):

High Resolution ◽

Pore Pressure ◽

Cost Optimization ◽

Oil Field ◽

Wellbore Stability ◽

Gulf Of Suez ◽

Geomechanical Model ◽

3D Geomechanical Model ◽

The Cost ◽

The Impact

Abstract Optimizing the number of casing strings has a direct impact on cost of drilling a well. The objective of the case study presented in this paper is the demonstration of reducing cost through integration of data. This paper shows the impact of high-resolution 3D geomechanical modeling on well cost optimization for the GS327 Oil field. The field is located in the Sothern Gulf of Suez basin and has been developed by 20 wells The conventional casing design in the field included three sections. In this mature field, especially with the challenge of reducing production cost, it is imperative to look for opportunites to optimize cost in drilling new wells to sustain ptoduction. 3D geomechanics is crucial for such cases in order to optimize the cost per barrel at the same time help to drill new wells safely. An old wellbore stability study did not support the decision-maker to merge any hole sections. However, there was not geomechanics-related problems recorded during the drilling the drilling of different mud weights. In this study, a 3D geomechanical model was developed and the new mud weight calculations positively affected the casing design for two new wells. The cost optimization will be useful for any future wells to be drilled in this area. This study documents how a 3D geomechanical model helped in the successful delivery of objectives (guided by an understanding of pore pressure and rock properties) through revision of mud weight window calculations that helped in optimizing the casing design and eliminate the need for an intermediate casing. This study reveals that the new calculated pore pressure in the GS327 field is predominantly hydrostatic with a minor decline in the reservoir pressure. In addition, rock strength of the shale is moderately high and nearly homogeneous, which helped in achieving a new casing design for the last two drilled wells in the field.

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Development of a new type of steel structure rack apparatus for 3D geomechanical model tests and structural integrity assessment

Boundaries of Rock Mechanics ◽

10.1201/9780203883204.ch169 ◽

2008 ◽

pp. 907-911

Author(s):

Y Li ◽

H Wang ◽

W Wang ◽

W Zhu ◽

J Han ◽

...

Keyword(s):

Structural Integrity ◽

Steel Structure ◽

Model Tests ◽

Geomechanical Model ◽

Integrity Assessment ◽

3D Geomechanical Model ◽

New Type

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Coupling a 3D geomechanical model with seismic velocity to predict pressure and the full stress tensor

10.3997/2214-4609.202038011 ◽

2020 ◽

Author(s):

M. Heidari ◽

M. Nikolinakou ◽

P. Flemings

Keyword(s):

Stress Tensor ◽

Seismic Velocity ◽

Geomechanical Model ◽

3D Geomechanical Model ◽

Full Stress Tensor

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Influence of Rock Plastic Behavior on the Wellbore Stability

10.2118/206557-ms ◽

2021 ◽

Author(s):

Elena Grishko ◽

Aboozar Garavand ◽

Alexey Cheremisin

Keyword(s):

Failure Criteria ◽

Wellbore Stability ◽

Standard Approach ◽

Plastic Behavior ◽

Element Formulation ◽

Geomechanical Model ◽

Plastic Properties ◽

Plastic Deformations ◽

3D Geomechanical Model

Abstract Currently, the standard approach to building a geomechanical model for analyzing wellbore stability involves taking into account only elastic deformations. This approach has shown its inconsistency in the design and drilling of wells passing through rocks with pronounced plastic properties. Such rocks are characterized by the fact that when the loads acting on them change, they demonstrate not only elastic, but also plastic (irreversible) deformations. Plastic deformations have an additional impact on the distribution of stresses in the rock of the near-wellbore zone on a qualitative and quantitative level. Since plastic deformations are not taken into account in the standard approach, in this case the results of the wellbore stability analysis are based on incorrectly calculated stresses acting in the rock. As a result, it can lead to misinterpretation of the model for analysis, suboptimal choice of trajectory, incorrect calculation of safe mud window and an incorrectly selected set of measures to reduce the risks of instability. The aim of this work is to demonstrate the advantages of the developed 3D elasto-plastic program for calculating the wellbore stability in comparison with the standard elastic method used in petroleum geomechanics. The central core of the work is the process of initialization of the elasto-plastic model according to the data of core tests and the subsequent validation of experimental and numerical loading curves. The developed 3D program is based on a modified Drucker-Prager model and implemented in a finite element formulation. 3D geomechanical model of wellbore stability allows describing deformation processes in the near-wellbore zone and includes the developed failure criteria. The paper shows a special approach to the determination of the mud window based on well logging data and core tests by taking into account the plastic behavior of rocks. An important result of this study is the determination of the possibility of expanding the mud window when taking into account the plastic criterion of rock failure.

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