Argentina 30 clay mineral South America 12 Clay minerals 10 hydrothermal alteration 8 kaolinite 8 Kaolinite 6 Soils 6 diagenesis 6 paleoclimate 6 ASTER 4 Ammonium anomalies 4 Andes 4 Cordillera Frontal 4 Hydrothermal alteration 4 Mining exploration guide 4 Miocene 4 Organic carbon 4 Paleogene 4 Remote sensing 4 SWIR reflectance spectroscopy 4 San Juan 4 Scanning electron microscopy 4 Western Hemisphere 4 World 4 X-ray diffraction 4 ammonium 4 chlorite 4 cordillera 4 depositional sequence 4