Detecting transience in slow evolution landscapes using cosmogenic nuclides and high resolution morphometry

Vincent Godard (1) , Andre Salgado (2) , Lionel Siame (1) , Jules Fleury (1) , Team Aster (1)

1 CEREGE - Centre européen de recherche et d'enseignement des géosciences de l'environnement
2 UFMG - Universidade Federal de Minas Gerais = Federal University of Minas Gerais [Belo Horizonte, Brazil]

<p>Transient evolution and adjustment to changing tectonic and climatic boundary conditions is an essential attribute of landscapes. We present a new approach to detect and quantify transience in slow erosion landscapes over 100 ka timescales. We compare curvature and cosmogenic nuclides measurements (¹⁰Be and ²⁶Al) at hilltop sites with predictions of hillslope diffusion theory, in the slowly evolving quartzitic Serra do Cip&#243; range in SE Brazil, and we observe a distinctive signature of an acceleration of denudation. The timing of this increase cannot be unequivocally associated with a single climatic event but is consistent with climatically-modulated important fluctuations in precipitation and erosion in this area during Middle and Late Pleistocene.</p>

Domaines: Géomorphologie; Tectonique; Géochimie

Vincent Godard, Andre Salgado, Lionel Siame, Jules Fleury, Team Aster. Detecting transience in slow evolution landscapes using cosmogenic nuclides and high resolution morphometry. EGU General Assembly, Apr 2021, Vienna, Austria. ⟨10.5194/egusphere-egu21-10051⟩. ⟨hal-03209511⟩