Multiple cosmogenic nuclides with different decay rates can be used to date exposure and burial of rocks over the timescales of radioactive decay. This paper reviews the development of such dating methods over the past ∼50 years, beginning with a historical perspective on early meteorite studies, and later focusing on recent examples in the terrestrial field using the ²⁶Al-¹⁰Be pair in quartz.

Two classes of terrestrial applications are discussed in detail. The first involves the use of ²⁶Al and ¹⁰Be in rock or sediment that has experienced a complex history of repeated exposure and burial. In these cases, the cosmogenic nuclides can only provide a minimum near-surface age. Examples include sediment from beneath desert sand dunes, and rocks from beneath cold-based glaciers. The second class of application uses ²⁶Al and ¹⁰Be to date discrete burial events, in cases where sediment has experienced a simple history of exposure followed by rapid burial. Examples include cave sediments, alluvial deposits, and sediment buried beneath glacial till. Finally, the half-lives of ²⁶Al and ¹⁰Be are discussed, with special attention given to discrepant estimates of the ¹⁰Be half-life. It is shown that geologic data are consistent with either half-life estimate of 1.51 m.y. or 1.34 m.y., but more closely conform to the shorter half-life.