Pinedale anticline, WY
US oil fields from above
7 reasons why oil is rare
Oil & NG Extraction “Wildcat” test wells (90% duds, lose $ but write-off)
Drill bit, “mud”, casing, directional drilling, blow-back control, flushing (9:1 water:oil), “fracking” tight reservoir
Definition/appraisal wells (bottom/sides) once outlined the pay zone
3D seismic + simulations
1st extraction gets < 30% of oil in place (OIP) 2nd : Repressurize by injecting water/nitrogen gas.
Pushes oil to wells, recovery boosted to ~50% Tertiary recovery: inject detergents/steam/CO2
Finally remove NG cap, stranding 30-40% oil
Well types & drill bits
Draining Oil/NG Field
11’
3
Other examples
Nitrogen injection Collapse
N. American Oil (NG) frontiers
Deep Gulf of Mexico Shale Oil (horizontal drilling) & “tight gas”
Not a recent technical breakthrough, merely sustained high oil prices
Unsustainable mode of natural gas extraction $5 M for fracking after $4M drilling / well
Canadian Tar (“Oil”) Sands (in situ processing) Arctic Ocean Shelf (horizontal drilling) East Coast
Off-shore oil infrastructureOff-shore drilling platform sequenceExtremely expensive, so big rush to move to next well
Reservoirs highly pressurized so fade rapidly
Oil very hot but deep water cold, so de-pressurized NG forms methane hydrate ices
up to 1994
X
“Tight” Oil in shale (animation) Mobilized by “fracking”
Oil field pyramidsReserves # of fields
Super giant >5 billion bbl 54
Giant 0.5-5 billion 263
Large 50-500 million 481
Others <50 million 70,000+
Field size
Flow rate
Many are> 60 yrs old
Many produce< 10 bbls / day