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A stream sediment survey was conducted in a semi-arid area in north-eastern Algeria. The survey includes a comparative study between results obtained from total analysis (XRF) and cold-extraction analysis (AAS), and assesses the relative success of the two data sets in delineating known mineralization and bedrock types. Samples were collected from ephemeral streams and water-bearing rivers and a sampling density of 1 sample km(-2) has been found to be effective in delineating most of the known mineralization and serpentinite bedrock. Anomalies occur mainly in the ephemeral streams but decay downstream after 1000 m, whereas in rivers values only rarely reach concentration levels above the regional background. Known lead, zinc and copper bearing veins, as well as the serpentinites, were well delineated by both analytical techniques. However, the iron mineralization could only be confirmed by the total analysis data set. In addition, new anomalies, similar to those of the sulphide mineralization, were discovered in the SW of the study area. Finally, it is suggested that the cold-extraction technique may offer an acceptable and cheaper alternative to total analysis for outlining serpentinites (cxCo and cxNi) and base-metal mineralization (cxCu, cxPb and cxZn).