What assumptions were made?
Reader Anonymous asserts Hubbert “… did not state under existing innovations” when peak oil production would be reached. Nevertheless, on page 24 of the initial Hubbert (1956) document, we discover the list below passage:
Secondary healing methods are gradualy being enhanced so that eventually a scmewhat larger but still unknown portion of the oil underground ought to be extracted than is now the case. Due to the fact that of the sluggishness of the secondary recovery procedure, however, it appears unlikely that any improvement that can be made within the next 10 to 15 years can have any considerable impact upon the date of conclusion. A more possible result ot improved healing will be to minimize the rate of decline after the culmination with regard to the rates revealed in Figure 21.
Here is Figure 21:
This entry was posted on November 2, 2022 by Menzie Chinn.
I would say that Hubbert did indeed condition his prediction on the innovations available. He likewise essentially held pretty continuous those assumed innovations for a 10-15 year window (so, to about 1966 to 1971)