The Upper Gulf Coast district of Texas is composed of 29 counties in the southeastern part of the state. It is identical with Texas Railroad Commission District No. 3.

There were 1,306 wells drilled in the district in 1949, which is a 15 per cent increase over 1948. Of these, 179 were drilled in search of new structures. This represents a decrease of 16 per cent under 1948 and resulted in the discovery of 28 new fields as compared with 22 new discoveries in 1948. These new discoveries consisted of 9 oil fields, 14 gas-condensate fields and 5 gas fields. All are of minor importance, the East Village Mills field, Hardin County, being the most important.

Considerable more reserves were added by development in old fields. Eleven hundred twenty-seven wells were drilled on known structures which resulted in the discovery of 73 new sands, 30 new reservoirs, and 10 important extensions. This is a decrease of 13 per cent under 1948. Most of these additions to reserves were the result of the discovery of new fault segments and new sands on old salt domes. Gradual but steady step-out drilling in the Gillock field, Galveston County, was the most important field development.

Five wildcat wells were completed in the Gulf of Mexico, one of which discovered the State No. 245 gas-condensate field, offshore from Galveston County.

Geophysical activity totaled 1,958 crew-weeks as compared with 2,415 crew-weeks in 1948. This represents a decrease of 19 per cent. The reflection seismograph was by far the most actively used instrument. The most active counties were Brazoria, Matagorda, Jefferson, Liberty, Galveston, and Wharton, accounting for 57 per cent of the total. Offshore work totaled 274 crew-weeks, representing 14 per cent of the total.

The total oil and condensate production in 1949 amounted to 145,419,014 barrels, which is a decrease of 42,130,690 barrels under 1948.

The reflection seismograph, in conjunction with subsurface geology, was the most successful exploration method.