CalVO geologist Mae Marcaida examines thin layers of volcanic ash s...
By Volcano Hazards Program
2013 (approx.)
Detailed Description
CalVO geologist Mae Marcaida examines thin layers of volcanic ash sandwiched between thick beds of sediment deposited by ancestral Mono Lake in eastern California. Each ash layer is evidence of a past explosive eruption of the Mono Craters, which began erupting about 65,000 years ago just south of present-day Mono Lake. Marcaida and her colleagues use the chemistry of magnetic minerals (titanomagnetites) found in the ash to uniquely "fingerprint" each layer and link it to one of the more than 30 eruptive centers that form the Mono Craters chain. For more information about the Mono Craters ash study see: Geochemical fingerprinting of Wilson Creek tephra layers (Mono Basin, California) using titanomagnetite compositions.
Sources/Usage
Public Domain.