Changes

<gallery mode=packed style=center heights=200px>

<gallery mode=packed style=center heights=200px>

File:GeoWikiWriteOff2021-Tayyib-Figure1.png|{{Figure number|1}}Movement of the tectonic plate (Earth’s outer shell: Crust & Lithospheric Mantle) generate in-situ stress (from Duarte & Schellart<ref>Duarte, J., C., and W. P. Schellart, 2016, Introduction to plate boundaries and natural hazards, ''in'' J. C. Duarte and W. P. Schellart, eds., Plate boundaries and natural hazards: AGU Geophysical Monograph Series 219, p. 1-10.</ref>).

File:GeoWikiWriteOff2021-Tayyib-Figure1.png|{{Figure number|1}}Movement of the tectonic plate (Earth’s outer shell: Crust & Lithospheric Mantle) generate in-situ stress (from Duarte & Schellart<ref>Duarte, J., C., and W. P. Schellart, 2016, Introduction to plate boundaries and natural hazards, ''in'' J. C. Duarte and W. P. Schellart, eds., Plate boundaries and natural hazards: AGU Geophysical Monograph Series 219, p. 1-10.</ref>).

File:GeoWikiWriteOff2021-Tayyib-Figure2.png|{{Figure number|2}}Summary of the different factors causing rock stress (from Amadei & Stephanson<ref>Amadei, B., and O. Stephansson, 1997, Rock stress and its measurement: Amsterdam, Netherlands, Spring Dordrecht, 490 p.</ref>).

File:GeoWikiWriteOff2021-Tayyib-Figure2.png|{{Figure number|2}}Summary of the different factors causing rock stress (from Amadei & Stephanson<ref name=AmadeiStephansson>Amadei, B., and O. Stephansson, 1997, Rock stress and its measurement: Amsterdam, Netherlands, Springer Dordrecht, 490 p.</ref>).

File:GeoWikiWriteOff2021-Tayyib-Table1.png|'''Table 1''' Activities requiring knowledge of in-situ stresses. (from Amadei & Stephanson,1997 as cited in Zhang, L 2016) [3.0]

File:GeoWikiWriteOff2021-Tayyib-Table1.png|'''Table 1''' Activities requiring knowledge of in-situ stresses. (from Amadei & Stephanson<ref name=AmadeiStephansson /> as cited in Zhang<ref name=Zhang>Zhang, L., 2016, Engineering properties of rocks: Amsterdam, Netherlands, Elsevier, 394 p.</ref>

</gallery>

</gallery>

 

 

<gallery mode=packed style=center heights=200px>

<gallery mode=packed style=center heights=200px>

File:GeoWikiWriteOff2021-Tayyib-Figure3.png|{{Figure number|3}}Illustration of resolving an oblique stress vector into normal and shear components.

File:GeoWikiWriteOff2021-Tayyib-Figure3.png|{{Figure number|3}}Illustration of resolving an oblique stress vector into normal and shear components.

File:GeoWikiWriteOff2021-Tayyib-Figure4.png|{{Figure number|4}}Stress tensor components of an infinitesimal cube, representing a point in the rock, and their alignment with the cartesian axes. (from Zhang, L., 2016) [3.1]

File:GeoWikiWriteOff2021-Tayyib-Figure4.png|{{Figure number|4}}Stress tensor components of an infinitesimal cube, representing a point in the rock, and their alignment with the cartesian axes (from Zhang<ref name=Zhang />).

File:GeoWikiWriteOff2021-Tayyib-Figure5.png|{{Figure number|5}}Special orientation in space where all shear stresses equal to zero. (from Zhang, L., 2016) [3.2]

File:GeoWikiWriteOff2021-Tayyib-Figure5.png|{{Figure number|5}}Special orientation in space where all shear stresses equal to zero (from Zhang, L.ref name=Zhang />).

</gallery>

</gallery>

<gallery mode=packed heights=300px style=centered>

<gallery mode=packed heights=300px style=centered>

GeoWikiWriteOff2021-Tayyib-Figure8.png|{{Figure number|8}}Summary of the stress determination methods. (modified from Heidbach et al. [5.0], 2016, and Moawietz et al. [6], 2020)   

GeoWikiWriteOff2021-Tayyib-Figure8.png|{{Figure number|8}}Summary of the stress determination methods. (modified from Heidbach et al. [5.0], 2016, and Moawietz et al. [6], 2020)   

GeoWikiWriteOff2021-Tayyib-Figure9.png|{{Figure number|9}}Workflow of the integrated approach for in-situ stress determination. (from Hudson et al, 2003, as cited in Zhang, L. 2016) [3.3]

GeoWikiWriteOff2021-Tayyib-Figure9.png|{{Figure number|9}}Workflow of the integrated approach for in-situ stress determination (from Hudson et al, 2003, as cited in Zhangref name=Zhang />).

</gallery>

</gallery>

====Wellbore Stability Analysis (Optimizing Well Placement)====

====Wellbore Stability Analysis (Optimizing Well Placement)====

In fields operated by ONGC in India, the horizontal stress orientations were determined using logging tools to help optimize the trajectory of future wells in any fault system (Tiwari, 2013). Figure 21 summarizes the different fault systems in which wells can be drilled. In a normally faulted system, the preferred drilling direction for inclined or horizontal wells is the minimum horizontal stress direction. The resulting wellbore tends to be more stable, thus requires lower mud weight and lower cost. Whereas, in a strike-slip or thrust fault system, the preferred drilling direction for inclined or horizontal wells is the direction of the maximum horizontal stress.

In fields operated by ONGC in India, the horizontal stress orientations were determined using logging tools to help optimize the trajectory of future wells in any fault system (Tiwari, 2013). Figure 21 summarizes the different fault systems in which wells can be drilled. In a normally faulted system, the preferred drilling direction for inclined or horizontal wells is the minimum horizontal stress direction. The resulting wellbore tends to be more stable, thus requires lower mud weight and lower cost. Whereas, in a strike-slip or thrust fault system, the preferred drilling direction for inclined or horizontal wells is the direction of the maximum horizontal stress.

[[File:GeoWikiWriteOff2021-Tayyib-Figure21.png|center|framed|{{Figure number|21}}Different types of fault systems due to in-situ stresses. (from Zhang, L., 2016) [3.4]]] 

[[File:GeoWikiWriteOff2021-Tayyib-Figure21.png|center|framed|{{Figure number|21}}Different types of fault systems due to in-situ stresses (from Zhang<ref name=Zhang />).  

====Sanding Analysis (Optimizing Well Completion)====

====Sanding Analysis (Optimizing Well Completion)====

 

 

3.0 3.1 3.2 3.3 3.4 Zhang, L., 2016, Engineering properties of rocks. Oxford, United Kingdom: Butterworth-Heinemann. 

4.0 4.1 4.2 4.3 Fossen, H., 2016, Structural geology. Cambridge, United Kingdom: Cambridge University Press.

4.0 4.1 4.2 4.3 Fossen, H., 2016, Structural geology. Cambridge, United Kingdom: Cambridge University Press.