CIW

Chemical index of weathering (CIW) from river sediment of Madagascar. The mean CIW of average 158 elemental compositions of upper continental crust (CIWUCC) is from Rudnick and Gao (2005). The three 159 geological domains (As, IK, and Ant) are indicated and are different in age and major lithological 160 composition (Tucker et al., 2014). Compositional and morphological effects are evident with low CIW.