The format of "North American Drilling Activity in 1981" is essentially the same as in former years with the exception that statistics from Mexico are no longer available and, therefore, future publications will cover only those activities occurring in the United States and Canada.

In 1981, Canada showed a decrease of 21.8% in total wells drilled (7,186) and a 22.1% decrease in the amount of footage drilled (26,954,094). The 205 new-field wildcat discoveries represented a success rate of 43%. Of these discoveries, 84 were in Alberta and 79 were in Saskatchewan. The new-field and new-pool wildcats accounted for 70.3% of the 1,926 exploratory discoveries. In Canada, 61.4% of the 3,137 exploratory wells drilled were successful.

In the United States, total drilling activity during 1981 increased 28.9% (80,537 wells), and footage drilled increased 26.8% (69,365 mi) compared with 1980. There were 1,423 new-field discoveries--a 6.2% increase over 1980. The ratio of new-field dry holes to producers was 4.66:1, and the success rate was 17.7%, substantially higher than the normal 9 to 11%.

Estimates of ultimate reserves discovered in 1981 in the United States showed an increase in volume of liquids and gases over those discovered in 1980. The new fields in 1981 discovered an estimated 652.99 million bbl of oil and condensate and 4.3 tcf of gas. However, 1981 production remains significantly greater than the amount found.