In the last 30 years, the mapping of bauxite deposits in Brazil has been carried out using drill holes. In this study, the refraction seismic method has been applied for the first time, with about 3000m of shallow profiles done on an experimental scale, at localities along the highway BR-10, as well as at Plato Esperança in the Jabuti region (PA), and near Açailândia county (MA), with the aim of delimitation of the bauxite layer. Although, the critical distance method has been used on some occasions to calculate thicknesses; this study has used the Generalized Reciprocal Method to process and interpret the data, to get the continuos delimitation of the layer being investigated. The GRM has an adventage compared to old traditional methods because, it delinates undulating refractors, infers undetected layers, and also is insensitive to dip angles up to 20 degrees. From the velocity analysis graph the velocity of the bauxite layer has been calculated, resulting in a mean of 840m/s. Using the time depth data it has been possible to map the bauxite, which has an irregular behavior and with a mean thickness of 5m. The geophysical research carried out at these areas turned out to be very important considering the fact that this method can be successfully applied to other regions having the same geological characteristics.
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