Soils on two sequences of terrace levels were studied in an area of the Amazon Basin in Bolivia with a perudic soil moisture regime to examine the effects of pedogenic processes over increasing increments of time. The two sequences each contain four topographic levels, including one level in the current floodplain. One sequence is derived from sediment from rocks in the Andes with relatively abundant weatherable minerals. The other sequence is in sediments from a foothills region from materials with low contents of weatherable minerals. Both areas had a presence of carbonates in the source area. Frequently flooded soils on the floodplains of both terrace sequences have high exchangeable base saturation percentages reflecting the influence of carbonate-rich flood water. Soils on all of the higher, older, non-flooding terraces have much lower base saturation percentages and high aluminum saturation percentages. Exchangeable potassium (and sodium) contents were low in all soils, even in the soil on the floodplain (youngest) site which formed in sediments with high contents of weatherable minerals. Soils exhibited increasing evidence of pedogenesis on increasing higher (older) terraces. The pedogenic processes that were evident included a decline in weatherable mineral (mica) content. The terrace sequence formed in sediments with a higher clay contents showed evidence of more clay illuviation. The transition from an eluvial to illuvial horizon in these soils was very indistinct. Stronger grades of soil structure are present in the older soils, but stronger grades of soil structure are also closely related to higher clay contents. Within the terrace sequence developed in sediments with a higher content of weatherable minerals, colors were generally redder on increasingly higher levels. Parent sediments in the other sequence have a distinctly red color making pedogenic development of color difficult to observe.