TECTONIC, ENVIRONMENTAL, AND HUMAN ASPECTS OF WEATHERING AND EROSION - A GLOBAL REVIEW USING A STEADY-STATE PERSPECTIVE

This review concerns the weathering process and how tectonics, geomorphic processes, and biology interact to control rates of denudation and the compositions of denudation products. In the first part of the review, I summarize several detailed syntheses of the tectonic and climatic aspects of chemical and physical denudation. Much of the review uses the under-explored concept of steady-state erosion to link chemical and physical erosion. The objective is to establish a context for comparing chemical, biological, physical, and human aspects of erosion. My choice of examples is affected by my field experience. I have worked primarily in neotropical watersheds, starting in the Amazon and Orinoco River systems. More recently, I have focused on small watersheds in Puerto Rico and Panama. I draw heavily from these data. In addition I use data from the Mackenzie River system and from studies of small, cold-climate watersheds, especially South Cascade Glacier in Washington. This combination of regional data sets allows comparison of similar tectonic environments in cold and warm climates. The impact of human activities in temperate zones is substantial and ubiquitous. -Author