With the help of infrared images from an area, remote sensing creates coloured images which show the content of clay minerals , carbonates and sulfates and their locations. Such an image can be taken, for example, by the ASTER instrument on satellite Terra: see Figure 2.4. This satellite was launched in 1999 by NASA, carrying the Japanese Advanced Spaceborne Thermal Emission and Reflection Radiometer (short ASTER) amongst others.
