GEOMAGNETISM ENVIRONMENTAL MAGNETISM PALEOMAGNETISM ARCHEOMAGNETIC DATING POTTERY SECULAR VARIATION PALEOMAGNETIC SECULAR VARIATION PALEOINTENSITY SOUTH AMERICA MAGNETIC MINERALOGY AND PETROLOGY ROCK AND MINERAL MAGNETISM ARCHEOINTENSTIY TIME VARIATIONS: SECULAR AND LONGER SPATIAL VARIATIONS: ALL HARMONICS AND ANOMALIES PALEOINTENSITY METHODS COOLING-RATE CORRECTION MICROWAVE