About This Item

Share This Item

The AAPG/Datapages Combined Publications Database

AAPG Bulletin


Volume: 60 (1976)

Issue: 8. (August)

First Page: 1153

Last Page: 1188

Title: North American Drilling Activity in 1975

Author(s): Robert R. Johnston (2)


Total drilling activity in North America increased in 1975 compared with 1974. The 43,692 total wells drilled in the United States, Canada, and Mexico is an increase of 16.5% compared with 1974, and the 36,962 mi of footage drilled is a 14.1% increase over 1974.

Canada showed an increase of 1% in total wells drilled (4,242) but a 4.4% decrease in the amount of footage drilled (13,928,589). The 142 new-field wildcat discoveries accounted for a 27.3% success, an all-time high. Of these discoveries, 112 were in Alberta and 15 were in Saskatchewan. The new-field wildcats and new-pool wildcats accounted for 495 of the 667 exploratory discoveries. Exploratory success in Canada was 40.4% of the 1,649 exploratory wells drilled.

Mexico in 1975 drilled 353 wells, exploratory and development. This was a 13.5% decrease compared with 1974. Of the total wells, 87 were exploratory and 266 were development. New-field wildcat drilling accounted for 6 discoveries and a success of 11%. Overall exploratory success was 17%, resulting in 13 discoveries, 8 of which were in the Salina basin.

For the United States, drilling activity increased 18.8%, and footage drilled increased 16.4%, compared with 1974. The new-field discoveries, 876, were the highest since 1956. The ratio of dry holes to producers was the lowest in history, 5.96:1, and inversely the success was the highest, 14.35, which is substantially higher than the normal 9.11%.

Estimates of ultimate reserves discovered in 1975 in the United States showed an increase in volume over that discovered in 1974. The new fields in 1975 discovered an estimated 579.9 million BO and condensate and 6.3 TCFG. However, 1975 production still remains significantly greater than the amount found.

Pay-Per-View Purchase Options

The article is available through a document delivery service. Explain these Purchase Options.

Protected Document: $10
Internal PDF Document: $14
Open PDF Document: $24

AAPG Member?

Please login with your Member username and password.

Members of AAPG receive access to the full AAPG Bulletin Archives as part of their membership. For more information, contact the AAPG Membership Department at [email protected].