Data for: A re-examination of the three most prominent Holocene tephra deposits in western Canada: Bridge River, Mount St. Helens Yn and Mazama

This supplementary dataset includes details on samples used in the study, previously published radiocarbon dates for Mount St. Helens Yn tephra, and all the glass geochemical data collected for Mazama, Bridge River, Mount St. Helens Yn, reference tephras and secondary standards.