A. Dunne, D. Elmore, P. Muzikar, Purdue University

Geomorphology 27 (1999) 3-11

A variety of geomorphic processes can be studied with the accumulation of cosmogenic nuclides in exposed materials. The quality of these studies depends on the accuracy of the isotope production rate. This production rate depends on several factors, many of which have been modeled either experimentally or theoretically.

The aim of this paper is to address the effects of geometric shielding (shielding which results from obstructions which partially or complete block incident cosmic radiation) for both the simple case of thick, cosmic-ray blocking obstructions and the more complex problem of shielding by depth on a sloped surface. This work is valid only for production of cosmogenic nuclides through spallation by high energy cosmic-ray secondaries in that it is based on the assumption that a decrease in the cosmic-ray flux will correspond proportionally to a decrease in the production rate.