『Abstract
The spatial and temporal changes in hydrology and pore water
elemental and87/86Sr compositions were used to determine
contemporary weathering rates in a 65 to 226 ky old soil chronosequence
formed from granitic sediments deposited on marine terraces along
coastal California. Cl-corrected Na, K and Si increased with depth
denoting inputs from the weathering of plagioclase and K-feldspar.
Solute 87/86Sr exhibited progressive mixing of sea
water-dominated precipitation with inputs from less radiogenic
plagioclase. Linear approximations to these weathering gradients
were used to determine plagioclase weathering rates of between
0.38 and 8.9×10-15 moles m-2 s-1.
The lack of corresponding weathering gradients for Ca and Sr indicated
short-term equilibrium with the clay ion exchange pool which requires
periodic resetting by natural perturbations to maintain continuity,
in spite of soil composition changes reflecting the effects of
long-term weathering.』
Introduction
Results
Conclusions
References