Changes

==Ductility-time plots==

==Ductility-time plots==

Ductility-time plots can be constructed from shale compaction curves and burial history curves. Burial history curves give the depth of burial of a top seal at a specific time. Shale compaction curves let us infer the shale density at a specific depth of burial and time.

Ductility-time plots can be constructed from shale compaction curves and burial history curves. Burial history curves give the depth of burial of a top seal at a specific time. Shale compaction curves let us infer the shale density at a specific depth of burial and time.

The following figure is a ductility-time plot for an Upper Jurassic top seal in the Central Graben, North Sea. The plot shows the paleodensity and inferred paleoductility during progressive burial of shales at the 141- and 151-m.y sequence boundaries. Prior to approximately [[length::100 m]].y, the Late Jurassic shale top seal had a density of 3 and was ductile. Strain prior to [[length::100 m]].y. would not contribute to seal risk. Any deformation occurring after [[length::100 m]].y. could have caused fracturing, given sufficiently high strains.

[[:file:evaluating-top-and-fault-seal_fig10-37.png|Figure 3]] is a ductility-time plot for an Upper Jurassic top seal in the Central Graben, North Sea. The plot shows the paleodensity and inferred paleoductility during progressive burial of shales at the 141- and 151-m.y sequence boundaries. Prior to approximately [[length::100 m]].y, the Late Jurassic shale top seal had a density of 3 and was ductile. Strain prior to [[length::100 m]].y. would not contribute to seal risk. Any deformation occurring after [[length::100 m]].y. could have caused fracturing, given sufficiently high strains.

 

==See also==

==See also==