Time as a Factor in the Genesis of Four Soils Developed in Recent Alluvium in Pennsylvania

摘要: Four soils developed in recent alluvium the Ridge and Valley physiographic region of central Pennsylvania were studied an attempt to relate chronologic age pedologic age. Wood or charcoal found at boundary between a buried soil profile each site was radiocarbon dated. These dates as follows: (i) < 205, (ii) 320 ± 80, (iii) 470 80 (iv) 1955 years B. P., indicate maximum which profiles developed. The relative distinctness horizons evaluated by field morphology rating scale, volume (in cross section) oriented illuvial clay films situ weathering minerals these that morphological properties are effective distinguishing differences alluvial differ approximately 1,500 age, but not when only few hundred years. data also cambic can develop <200 still present after 2,000 formation.