During 1970 the oil industry in North America drilled more than 30,000 mi of hole with 33,270 wells. Compared with 1969 this is a substantial decrease of approximately 12% in both wells and footage.
The 29,467 wells in the United States represented a decrease of 13.5% and the 3,280 wells in Canada, a decrease of 10.4%. Mexico was the exception; the total of 523 wells is a slight increase of 1% compared with 1969.
In the face of this drop in drilling activity, new-field discoveries in 1970 reported an increase in new oil and gas reserves from the 1969 reserves. The report of 4 major field discoveries caused this increase. Without these 4 fields, the estimated reserves of the other 125 new-field discoveries in 1970 would have declined from 1969 figures in about the same ratio as the drop in exploration drilling activity.
The major fields on the North Slope of Alaska were reported for the first time. These field reserves are handled separately because of their very large size and because of their geographic remoteness.
Exploratory drilling in the U.S. continues the long-term downward trend apparent since 1956. In some categories of wells, the 1970 numbers are the lowest in 21 years.
The amount of future domestic reserve additions from new-field discoveries also will decrease if this downtrend in exploration drilling continues.