Since the 1960s, the Amazonian forest has been shrinking with the advance of primarily commercial cultivated areas. The pattern is being strengthened by high population growth and the migration of populations towards these newly deforested pioneer fronts. These trends are causing space to be appropriated to the detriment of forested areas. It has become essential to be able to locate areas on the pioneer front quickly and systematically in order to characterize new phases in advancing deforestation as they occur. However, satellite tools with high spatial resolution are not suited to monitoring of this type, as their temporal resolution is too broad and data processing is characteristically complex. Although low–resolution satellite images therefore seem more appropriate to these analyses, they can raise major problems when the target areas are very specific. In order to use imagery with low spatial resolution, such as SPOT-VEGETATION images, this study proposes a monitoring methodology based on a deforestation front of very small size. The method could be extrapolated to other deforestation fronts to investigate new areas to be monitored and thus establish diagnoses of the temporal dynamics of landscape transformation.