The diffusion of helium through sedimentary rocks
Abstract
Helium is produced by the radioactive decay of the nuclides of certain minerals and it is commonly assumed that a portion of this helium migrates from its source through overlying rocks to the atmosphere. In this paper the effect of diffusion control on the migration of helium in sediments has been evaluated by the construction of a series of mathematical models to represent a wide range of practical situations. These models range from that with a single infinite, uniform layer of sediment to that with n different, finite uniform layers of sediments. The problem has been reduced to onedimensional diffusion with the PreCambrian basement rocks as the source of helium and the diffusion equation has been solved for this system with differing boundary conditions. The nlayer models have been evaluated by a series of suitable approximations at each of the interfaces between the layers and in this way the relationship between the helium concentrations in successive layers has been obtained. The effect of these approximations has been illustrated by using them to evaluate some of the singlelayer models. Some of the singlelayer and twolayer models have been evaluated using representative values for the parameters introduced in the analysis.
 Publication:

Geochimica et Cosmochimica Acta
 Pub Date:
 March 1961
 DOI:
 10.1016/00167037(61)901119
 Bibcode:
 1961GeCoA..22..106N