Keywords

A long, narrow, sinuous, steep-sided ridge composed of irregularly stratified sand and gravel that was deposited by a subglacial or englacial stream flowing between ice walls or in an ice tunnel of a stagnant or retreating glacier, and was left behind when the ice melted.  It may be branching and is often discontinuous, and its course can be at a high angle to the edge of the glacier.  Eskers range in length from less than 100 m to more than 500 km (if gaps are included), and in height from 3 m to more than 200 m.

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.