Drilling:
In 1972, Petroleos Mexicanos drilled 431 wells, 85 less than in 1971. Of the 431 wells, 143 were exploratory, 14 more than in 1971. Of the exploratory wells, 4 did not reach their objective because of mechanical failure. A total of 288 development wells also was drilled.

The total footage drilled during 1972 was 3,727,563 ft (1,136,452 m). Of this amount, 1,460,118 ft (445,158 m) was exploratory drilling, 4.9% more than in 1971. The average depth of exploratory wells was 10,210 ft and of development wells, 7,873 ft.

The success of new-field wildcats was 18.6%; the success of other types of exploratory wells was 24.5%.

Exploratory activities:
(1) Exploratory parties: during 1972, 75 exploration parties were in operation. Of these, 22 did field mapping; 17, subsurface mapping; 23, seismic mapping onshore and 5, seismic mapping offshore; 5, gravity meter; 1, terrestrial magnetometer; and 2, combination magnetometer and gravity meter. (2) Exploratory wells: in 1972, 143 exploratory wells were drilled. Of these, 4 did not reach their objective, because of mechanical failure. Of the 139 remaining wells, 88 were new-field wildcats, 11 of which were oil producers and 5, gas producers. This gives an exploration success of 18.6%. Of the exploratory failures, 46 were extension wells for deeper pool wildcats on producing structures; 9 were stratigraphic tests in new areas. Of the various types of exploratory wells, the success percentag was 24.5.

Annual production of oil and gas:
The annual production of crude oil and condensate during 1972 was 185,000,000 bbl, 4.08% more than in 1971. The daily liquid production was 505,494 bbl and the daily gas production was 1,803.8 MMcf. Total annual gas production was 660,232 MMcf.

Reserves:
At year end, the reserves of oil and gas reached 5,387.8 million bbl, a decline of 40,495 bbl with respect to 1971.