Modelling of Time-Dependent Wellbore Collapse in Hard Brittle Shale Formation under Underbalanced Drilling Condition

<table class="figure-group"><tr class="fig-image" id="a"><td><object data="https://static.hindawi.com/articles/geofluids/volume-2019/1201958/figures/1201958.fig.004a.svgz" name="1201958.fig.004a" type="image/svg+xml"></object></td></tr><tr class="fig-caption"><td><b>(a) </b>Confining pressure 0 MPa</td></tr><tr class="fig-image" id="b"><td><object data="https://static.hindawi.com/articles/geofluids/volume-2019/1201958/figures/1201958.fig.004b.svgz" name="1201958.fig.004b" type="image/svg+xml"></object></td></tr><tr class="fig-caption"><td><b>(b) </b>Confining pressure 25 MPa</td></tr><tr class="fig-image" id="c"><td><object data="https://static.hindawi.com/articles/geofluids/volume-2019/1201958/figures/1201958.fig.004c.svgz" name="1201958.fig.004c" type="image/svg+xml"></object></td></tr><tr class="fig-caption"><td><b>(c) </b>Confining pressure 50 MPa</td></tr></table>

<div>Triaxial test results of original rock in the W-82 well (depth 4150 m).</div>

Geofluids

fig4

Figure 4

Figure 4: Modelling of Time-Dependent Wellbore Collapse in Hard Brittle Shale Formation under Underbalanced Drilling Condition 