Preliminary evaluation of bedrock potential for naturally occurring asbestos in Alaska

Abstract

Naturally occurring asbestos (NOA) develops in predictable geologic settings worldwide. Various geologic units throughout Alaska include rock types that could potentially host naturally occurring asbestos minerals. This report and digital data release show geologic map units throughout Alaska rated according to their interpreted potential to host NOA. To summarize locations of known asbestos occurrences, we searched the U.S. Geological Survey's (USGS's) Alaska Resource Data File (http://ardf.wr.usgs.gov) and Mineral Resource Data System (http://mrdata.usgs.gov/mineral-resources/mrds-ak.html) for references to asbestos in Alaska and compiled the resulting 62 documented asbestos occurrences. To better predict additional locations where NOA may exist in Alaska, we compiled published geologic mapping throughout the state, developed a set of criteria to rate relative NOA potential according to rock type, and assigned a rating to each bedrock map unit. The products of this work are (1) a report and summary maps that present an overview of the problem and discussion of the data compilation methods and information sources, (2) a table listing known occurrences of naturally occurring asbestos in Alaska, and (3) digital geologic maps that portray the extent of various bedrock units that have been mapped throughout Alaska and a ranking of their interpreted relative potential for hosting asbestos minerals.