Changes

==Determination Methods of Stress==

==Determination Methods of Stress==

Determination methods of in-situ stresses can be classified into three categories as shown in figure 8. The loading method involves disturbing the in-situ stress condition in the rock such as pumping high pressure fluid into the formation to create fractures. The relief method involves isolating the rock sample partially or completely from the surrounding rocks and observe the natural rock response to the in-situ stress. Other methods can be used to deduce the in-situ stress in the rock such as geological and geophysical method. Since stress cannot be measured directly, the methods rely on the measurements of any change in rock volume or shape (Strain). Figure 9 shows the integration of the different methods in one workflow to infer the in-situ stress state.

Determination methods of in-situ stresses can be classified into three categories as shown in figure 8. The loading method involves disturbing the in-situ stress condition in the rock such as pumping high pressure fluid into the formation to create fractures. The relief method involves isolating the rock sample partially or completely from the surrounding rocks and observe the natural rock response to the in-situ stress. Other methods can be used to deduce the in-situ stress in the rock such as geological and geophysical method. Since stress cannot be measured directly, the methods rely on the measurements of any change in rock volume or shape (Strain). Figure 9 shows the integration of the different methods in one workflow to infer the in-situ stress state.

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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 Zhang, L. 2016) [3.3]