Growth - Are We Understimating Recent Discoveries?

King, Keith C.¹ (1) ExxonMobil Exploration Company, Houston, TX

Estimates of oil resources in established fields tend to grow as inplace potential is more completely understood and recovery factors improve with continued development. This study evaluates historical growth and examines factors that will control future growth. Resulting findings are (1) historical oil resource growth has been greater than newly discovered resources over the past 25 years (2) uncertain and variable factors control future growth and (3) estimates of future growth based on these factors could be from 200 to 1000 GBO, broadly similar to the USGS estimates. This analysis calculates past resource additions by comparing reported field sizes in 5 year intervals between 1981 and 2006 of the IHS global database of discovered fields. Historical resource growth during this period added 530 GBO. Measured on a yearly basis these additions averaged 2% per year up to 70 years after discovery. Predicting future growth is more speculative than measuring previous growth since factors that influence future field growth may not follow the same trends as observed in the historical study. By looking at global recovery efficiencies of fields in various stages of development we can estimate potential resource additions associated with fields as they move from undeveloped to developed-with-IOR. In conclusion, there are numerous factors that will determine future growth, technology development to tackle difficult reservoir, technology transfer to oil rich regions, shifts in reporting practice and pace of development investment. Monitoring how these factors evolve and interplay will significantly impact future oil supplies.