The total of wells drilled in south Texas in 1962 decreased by 3.7% from 1961. Exploratory drilling decreased by 8.5% and development drilling decreased by 2%. Wildcat discoveries were 23.7% greater than in 1961. The wildcat success ratio of 1:6 is an increase over the success ratio of 1:8 in 1961. Production increased in 1962, oil by 2.4% and gas by 4.6%. The first discovery of commercial quantities of hydrocarbons in the James Limestone and the Sligo Limestone in south Texas will encourage additional exploration for reserves in the Cretaceous section below the Edwards Limestone. Two Wilcox discoveries in Duval County and a multipay Frio discovery in San Patricio County give promise of being major fields. Geophysical activity decreased by 18.7% from 1961. The largest decrease was in seismic activity in the Cretaceous and Jurassic trend.