Keywords

Soil gases are the gases found in the air space between soil components. The primary soil gases include nitrogen, carbon dioxide and oxygen. The oxygen is critical because it allows for respiration of both plant roots and soil organisms. Other natural soil gases are atmospheric methane and radon.

Geological keywords, such as “granite”, “lake”.  The definitions are generally taken from the AGI Glossary of Geology.  Keywords with a geographic context (e.g. Cape Smith Fold Belt, Selwyn Basin, Grenville Province) are assigned to a separate category.