U.S. SEISMIC CREW COUNT DROPS 6 PCT IN FEBRUARY The number of seismic crews searching for oil and gas in the United States dropped by nine to a total of 151 crews, a decrease of six pct from January, the Society of Exploration Geophysicists said. The February total represented a 49 pct decrease from February 1986. Worldwide, the association's monthly survey showed that seismic exploration for oil and gas increased to 395 in February, up three from the month before. Africa added three seismic crews, the Middle East increased by two and the Far East added one while reductions were reported in Central and South America, Europe and the United States.