Changes

* Bridging off by swelling formations or a collapsed hole.

* Bridging off by swelling formations or a collapsed hole.

[[file:fishing_fig1.png|thumb|{{figure number|1}}Differential sticking. Copyright: Exploration Logging, 1979.]]

[[file:fishing_fig1.png|thumb|{{figure number|1}}Differential sticking. © Exploration Logging, 1979.]]

[[file:fishing_fig2.png|thumb|{{figure number|2}}Key seating. Copyright: Short, 1981; courtesy of PennWell Books.]]

[[file:fishing_fig2.png|thumb|{{figure number|2}}Key seating. © Short, 1981; courtesy of PennWell Books.]]

When material is left in the hole due to these or other factors, a decision must be made whether to try to recover the material, to sidetrack around the original material, to abandon the well, or to attempt to complete in a shallower zone. Because all but the first of these options are costly, and the last is often undesirable, an attempt to recover the fish is almost always made.

When material is left in the hole due to these or other factors, a decision must be made whether to try to recover the material, to sidetrack around the original material, to abandon the well, or to attempt to complete in a shallower zone. Because all but the first of these options are costly, and the last is often undesirable, an attempt to recover the fish is almost always made.