The information and graphs here are from a summary of the Hirsch Report, which was commissioned (then promptly buried) by the Department of Energy:
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Oil Discoveries in Billions of Barrels 1930-2005
This chart, not part of the Hirsch Report but available on many oil statistic websites shows the oil discoveries in Billions of Barrels over the past 75 years. The big spikes are: late 30's Texas, late 40's Saudi Arabia, last tall spike in early 70's is the North Sea.
Oil Discoveries minus Production, we started using more that we discovered in the mid 80's
This chart, from the Hirsch Report and found on many oil statistics websites, shows production and consumption combined. As the chart shows for years the worlds oil companies found more oil than they were producing. But the picture goes into the red in the mid 80's. From that time to present we are using more oil than oil being discovered.
Same chart with Drilling Overlay, Yellow line = drilling.
More drilling worldwide did not stop the negative numbers. This is the same chart as above but also showing the feet of wildcat drilling for oil. This chart is used by many to show that more exploration world wide did not stop the numbers from remaining n the red. This chart is used by many experts to validate the notion that we have passed the era of cheap oil.
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From Hirsch's Congressional testimony:
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PRODUCTION PEAKING
World oil demand is forecast to grow 50 percent by 2025. To meet that
demand, ever-larger volumes of oil will have to be produced. Since oil production
from individual oil fields grows to a peak and then declines, new fields must be
continually discovered and brought into production to compensate for the
depletion of older fields and to meet increasing world demand. If large quantities
of new oil are not discovered and brought into production somewhere in the
world, then world oil production will no longer satisfy demand. Peaking means
that the rate of world oil production cannot increase; it does not mean that
production will suddenly stop because there will still be large reserves remaining.
As indicated in Table I, some forecasters believe that world oil production
peaking might occur very soon. Others argue that we may have more than a
decade of plentiful oil.
Until recently, OPEC assured the world that oil supply would continue to be
plentiful, but that position is changing. Some in OPEC are now warning that oil
supply will not be adequate to satisfy world demand in 10-15 years. Dr. Sadad
al-Husseini, retired senior Saudi Aramco oil exploration executive, is on record as
saying that the world is heading for an oil shortage; in his words “a whole new
Saudi Arabia (will have to be found and developed) every couple of years'' to
satisfy current demand forecasts. So the messages from the world’s
“breadbasket of oil” are moving from confident assurances to warnings of
approaching shortage.
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http://www.nyswda.org/LegPosition/HirschReport.htm