isla - kars
- island
- island arc
- island arc tholeiite
- iso grade map
- isoanomalic contour line
- isobar
- isobaric chart
- isobath
- isochemical metamorphism
- isochemical series
- isochore map
- isochromatic line
- isochron age
- isochron dating method
- isochrone
- isochrone age of interior of minerals
- isochronism
- isoclasite
- isoclinal
- isoclinal fold
