Wells drilled in the Upper Texas Gulf Coast during 1980 totaled 1,826, up over 35% from the previous year total of 1,344 and over 13% from the 1977 decade high of 1,584. Onshore development drilling accounted for most of the increase; activity was up 50% from 1979. Onshore exploratory drilling continued to climb, up from 406 wildcats in 1979 to 420 in 1980. Of these, 42% were in the Oligocene Trend, which remains the most actively explored trend in the coast. The onshore success rate was also up slightly, from 50 to 51 discoveries this year. Offshore exploratory drilling was on the rise in 1980, up 15%, while development drilling continued the 1978 decline trend, down 21% this year. Onshore geophysical activity totaled 1,174 crew weeks, up 224 from the 950 crew weeks in 1 79 and up 182 from the decade high of 992 in 1978. Offshore seismic activity increased to 156 crew weeks, a record high for the last 6 yr. In two state and one federal lease sales, the industry spent $1,480,820,025.03, acquiring 1,357,485.52 ac.