Changes

[[file:evaluating-top-and-fault-seal_fig10-41.png|thumb|300px|{{figure number|3}}traps with a maximum post-100 Ma incremental strain > 1.6% are dry (traps H, I, J). Traps with a strain <1.6% are still intact and contain hydrocarbons (traps B-G). Trap A, a structure with very low strain, is dry because of natural hydraulic fracturing. Traps that were dry ue to other causes such as lack of reservoir or source are not included in this plot.]]

[[file:evaluating-top-and-fault-seal_fig10-41.png|thumb|300px|{{figure number|3}}traps with a maximum post-100 Ma incremental strain > 1.6% are dry (traps H, I, J). Traps with a strain <1.6% are still intact and contain hydrocarbons (traps B-G). Trap A, a structure with very low strain, is dry because of natural hydraulic fracturing. Traps that were dry ue to other causes such as lack of reservoir or source are not included in this plot.]]

Incremental strain analysis of a group of successes and failures in the Central Graben defines a strain threshold at approximately 1.6%. In [[:file:evaluating-top-and-fault-seal_fig10-41.png|Figure 3]], traps with a maximum post-100 Ma incremental strain > 1.6% are dry (traps H, I, J). Traps with a strain <1.6% are still intact and contain hydrocarbons (traps B-G). Trap A, a structure with very low strain, is dry because of natural hydraulic fracturing. Traps that were dry ue to other causes such as lack of reservoir or source are not included in this plot.

Incremental strain analysis of a group of successes and failures in the Central Graben defines a strain threshold at approximately 1.6%. In [[:file:evaluating-top-and-fault-seal_fig10-41.png|Figure 3]], traps with a maximum post-100 Ma incremental strain > 1.6% are dry (traps H, I, J). Traps with a strain <1.6% are still intact and contain hydrocarbons (traps B-G). Trap A, a structure with very low strain, is dry because of [[Natural hydraulic fracturing of top seals|natural hydraulic fracturing]]. Traps that were dry ue to other causes such as lack of reservoir or source are not included in this plot.

This empirical threshold provides an important tool for evaluating top seals. Prospects can be evaluated before drilling using incremental strain analysis. In this case, high-risk prospects are those with strains exceeding the threshold of 1.6%. Low-risk prospects are those with strains below the threshold.

This empirical threshold provides an important tool for evaluating top seals. Prospects can be evaluated before drilling using incremental strain analysis. In this case, high-risk prospects are those with strains exceeding the threshold of 1.6%. Low-risk prospects are those with strains below the threshold.