Abstract

Understanding the relationship between subsurface flow paths on hillslopes and chemical weathering of bedrock is fundamental to understanding the timing and mechanisms that weather bedrock to saprolite. The link between chemical weathering of bedrock and contact time with reactive water along flow paths motivates this study. Water drives the chemical alteration of rock into saprolite, yet connected porosity generally declines with depth into the weathered profile. Saprolite formation, therefore, reflects coupled weathering and permeability development over time. This study uses numerical modeling and soil-moisture monitoring to explore the hydrology of the unsaturated zone and the influence of fracture density, hillslope gradient, and permeability contrasts within the saprolite development horizon on saprolite development.

Citation

Langston, A.L., Tucker, G.E., Anderson, R.S., and Anderson, S.P. (2011): Exploring Links between Vadose Zone Hydrology and Chemical Weathering in the Boulder Creek Critical Zone Observatory. Applied Geochemistry 26(S1): S70-S71.. DOI: 10.1016/j.apgeochem.2011.03.033