Marquard, J., R.E. Aalto, T.T. Barrows, B.A. Fisher, A.A. Aufdenkampe, and J.O. Stone. 2018. Earth Surfaces Processes and Landforms.
Understanding natural soil redistribution processes is essential for measuring the anthropogenic impact on landscapes. Although meteoric 10Be has been used to determine erosion processes within the Pleistocene and Holocene, fewer studies have used the isotope to investigate the transport and accumulation of the resulting sediment. Here we use meteoric 10Be in hilltop and valley site soil profiles to determine sediment erosion and deposition processes in the Christina River Basin (PA, USA). The data indicate natural erosion rates of 14 to 21 mm 10‐3 yr and soil ages of 26,000 to 57,000 years in hilltop sites. Furthermore, valley sites indicate an alteration in sediment supply due to climate change (from the Pleistocene to the Holocene) within the last 60,000 years and sediment deposition of at least 0.5–2 m during the Wisconsinan glaciation. The change in soil erosion rate was most likely induced by changes in geomorphic processes; probably solifluction and slope wash during the cold period, when ice advanced into the mid latitudes of North America. This study shows the value of using meteoric 10Be to determine sediment accumulation within the Quaternary and quantifies major soil redistribution occurred under natural conditions in this region.
This material is based upon work supported by the National Science Foundation. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation.