John Karlo- Your Next Dry Hole-Seal Failure

Two of the major components in conventional prospects, trap geometry, and reservoir presence can be so fully evaluated that these components often carry minimal exploration risk. In part as a consequence of this, the primary cause for dry holes and sub-economic discoveries has now shifted to being seal failure. A survey done by Schlumberger proposes that 45% of industry dry holes are owing to lack of seal. A recent paper by Rudolph and Goulding (2017) supports this describing a lookback study of exploration drilling by Exxon for a ten year period and finding that 50% of their dry holes were owing to trap failures and this percentage actually increased to 60% of dry holes in mature well understood plays. Despite this, there is a major mismatch between the importance of seals in hydrocarbon trapping and the sophistication of seal evaluation. In most workflows, seal evaluation is commonly done with little technical rigor during the time squeeze at the end of a prospect evaluation and the seal evaluation is often so superficial as to be nearly meaningless.