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  | isbn    = 0-89181-602-X

  | isbn    = 0-89181-602-X

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We often assume that a structure remains static when [[Calculating charge volume|charged]] by petroleum. Traps may be charged during structural growth, and [[accumulation]]s can be partially or completely spilled by later structural [[deformation]].

We often assume that a structure remains static when [[Calculating charge volume|charged]] by petroleum. Traps may be [[Calculating charge volume|charged]] during structural growth, and [[accumulation]]s can be partially or completely spilled by later structural [[deformation]].

Traps charged during structural growth are not destroyed by spillage as long as the trapping geometry is maintained during deformation because petroleum migrates with the structural closure much faster than the rate of structural growth.<ref name=ch11r15>Hubbert, M., K., 1953, [http://archives.datapages.com/data/bulletns/1953-56/data/pg/0037/0008/1950/1954.htm Entrapment of petroleum under hydrodynamic conditions]: AAPG Bulletin, vol. 37, p. 1954–2026.</ref> Conversely, if structural closure is destroyed during deformation, spillage occurs rapidly.

Traps charged during structural growth are not destroyed by spillage as long as the trapping geometry is maintained during deformation because petroleum migrates with the structural closure much faster than the rate of structural growth.<ref name=ch11r15>Hubbert, M., K., 1953, [http://archives.datapages.com/data/bulletns/1953-56/data/pg/0037/0008/1950/1954.htm Entrapment of petroleum under hydrodynamic conditions]: AAPG Bulletin, vol. 37, p. 1954–2026.</ref> Conversely, if structural closure is destroyed during deformation, spillage occurs rapidly.

Traps in which faults form part of the closure are especially susceptible to spillage during structural growth because movement on the fault may result in leakage. Movement on the fault is also likely to juxtapose permeable lithologies across the fault at some point in the movement. [[:file:predicting-preservation-and-destruction-of-accumulations_fig11-2.png|Figure 2]] shows spillage resulting from movement on a sealing fault.

Traps in which faults form part of the closure are especially susceptible to spillage during structural growth because movement on the fault may result in leakage. Movement on the fault is also likely to juxtapose permeable lithologies across the fault at some point in the movement. [[:file:predicting-preservation-and-destruction-of-accumulations_fig11-2.png|Figure 2]] shows spillage resulting from movement on a sealing fault.

As the fault displaces the units, an early charged trap (A, at t = 1) is juxtaposed against a sandstone at some later time (B, at t = 2). This probably will result in rapid spillage. If further fault movement restores favorable seal juxtaposition (C, at t = 3), additional petroleum charge will be needed to fill the new trap.

As the fault displaces the units, an early-[[Calculating charge volume|charged]] trap (A, at t = 1) is juxtaposed against a sandstone at some later time (B, at t = 2). This probably will result in rapid spillage. If further fault movement restores favorable seal juxtaposition (C, at t = 3), additional petroleum charge will be needed to fill the new trap.

==Evaluating spillage==

==Evaluating spillage==