Special report; geophysical activity in 1987

Statistical data on worldwide geophysical activity in 1987 are presented in this report. Data were gathered from survey questionnaires that were mailed to over 475 oil companies, contractors, government agencies, and institutions throughout the free world. Information has been collected from all users of geophysical techniques in the areas of petroleum, mining, groundwater, and geothermal exploration, and from those who employ geophysical methods in engineering, environmental, oceanography, and research. Two hundred fifteen questionnaires were returned with data for this report. This compares to 251 questionnaires returned with data for the 1986 report and 214 returns for the 1985 report.