Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
8906909 | Earth and Planetary Science Letters | 2018 | 11 Pages |
Abstract
In contrast to the previous studies, we do not observe an increase in the OSL sensitivity of quartz with transport distance; for example, Tapajós and Xingu Rivers show more sensitive quartz than Solimões and Madeira Rivers, even though the latter have a significantly larger catchment area and longer sediment transport distance. Interestingly, high sensitivity quartz is observed in rivers draining relatively stable Central Brazil and Guiana shield areas (denudation rate ξ=0.04 mmyrâ1), while low sensitivity quartz occurs in less stable Andean terrains (ξ=0.24 mmyrâ1). An apparent linear correlation between quartz OSL sensitivity and denudation rate suggests that OSL sensitivity may be used as a proxy for erosion rates in the Amazon basin. Furthermore, luminescence sensitivity measured in sand or silt arises from the same mineral components (quartz and feldspar) and clearly discriminates between Andean and shield sediments, avoiding the grain size bias in provenance analysis. These results have implications for using luminescence sensitivity as a proxy for Andean and shield contributions in the stratigraphic record, providing a new tool to reconstruct past drainage configurations within the Amazon basin.
Related Topics
Physical Sciences and Engineering
Earth and Planetary Sciences
Earth and Planetary Sciences (General)
Authors
A.O. Sawakuchi, M. Jain, T.D. Mineli, L. Nogueira, D.J. Jr., C. Häggi, H.O. Sawakuchi, F.N. Pupim, C.H. Grohmann, C.M. Chiessi, M. Zabel, S. Mulitza, C.E.M. Mazoca, D.F. Cunha,