Wells drilled in the Upper Texas Coast during 1977 totaled 1,584, an increase of 37% over 1976. Offshore development drilling increased 142% from 77 wells in 1976 to 186 in 1977, and onshore development activity was up 51.7%. During 1977, 532 exploratory wells were drilled onshore compared to 462 in 1976. The Oligocene was the most actively explored trend, accounting for most of the significant onshore discoveries. The Cretaceous-Jurassic trend showed a 67% increase in wildcat drilling over 1976. Additionally, seismic activity sharply increased in this trend. Offshore exploratory drilling continued its 3-year decline; however, significant discoveries were reported from Miocene and upper Oligocene rocks. It is estimated that the discovery of Shipwreck field (Galveston area will significantly increase offshore Texas gas reserves. In 1 federal and 3 state lease sales held in 1977, companies acquired 367,315 acres, predominantly bay and Gulf of Mexico tracts.