Study of the erosion rates in the upper Maracujá Basin (Quadrilátero Ferrífero/MG, Brazil) by the in situ produced cosmogenic 10Be method

摘要

The present work quantifies the erosive processes in the two main substrates (schists-phyllites and granites-gneisses) of the upper Maracujá Basin in the Quadrilátero Ferrífero/MG, Brazil, a region of semi-humid tropical climate. Two measuring methods of concentration were used: (i) in situ produced 10Be in quartz veins (surface erosion rates) and (ii) 10Be in fluvial sediments (basin erosion rates). The results confirm that (i) erosion tends to be more aggressive close to the headwaters than in the lower parts of the basin and (ii) the region is now affected by dissection. Copyright ? 2006 John Wiley & Sons, Ltd.