This paper illustrates the benefits of Digital Elevation Models (DEM) created from SPOT images for the exploration of sedimentary basins. We chose two examples in Spain : one located in the Ebro sedimentary basin, the other located on the southern border of the Soria basin. The data used consisted of a pair of SPOT panchromatic images, a SPOT XS image and a Landsat TM image for the first area and a pair of SPOT XS images for the second test area. The work consists of making up a 3D database, followed by interpretation of stereo pairs computed from ortho-images and the DEM. The interpretations are made on a stereoscopic desk and the results are digital files of the observed faults and lithology. Synthesis of perspective views made at the same time provide a better understanding of the structures and help to test their geometric consistency. Finally this study involves making calculations on the geometry of these interpretations : we demonstrate that we can accurately measure layer directions and dips, sediment thicknesses and fault throws. Thus knowledge about relief given by DEM helps to interpret remote detection images in 3D space, and particularly to accurately quantify the results of these interpretations.