From April 12 to 19, 1984, dust was collected by cascade impactor on Fuerteventura Island, 100 km from the Saharan coast. The samples were analyzed by X ray fluorescence spectrometry (elemental composition), by X ray diffraction (mineral constituents), and by scanning electron microscope (SEM) and energy dispersive X ray analyzer (EDXA) examination (shape, surface features, and mineralogy of particles), with the aim of determining the possible source areas of the dust. On the scale of dust clouds, another method allowed us to define the displacements of the dust: using remote sensing (METEOSAT II, National Oceanic and Atmospheric Administration (NOAA)) and computing trajectories for any starting or ending point at any time. These various methods gave complementary results and pointed out two successive episodes of dust with two different continental origins. The first originated from a nearby source in the Souss plain (southern Morocco) and was characterized by very fine quartz particles. The second drifted above more remote calcareous regions. This study allows us to show how different methods can be used to characterize dust and to find the source areas. The results suggest some general questions about the occurrence of coarse particles in the atmosphere and their role in the atmospheric deposition flux budget. ¿American Geophysical Union 1987