"The geology of the northeastern Brooks Range does not match anything that we've studied in the neighboring region of North America," said Strauss, the research lead of the study.

Graptolites of Early and Middle Ordovician age have been found in a thin, phyllitic slate unit that underlies the Baird Group in the Baird Mountains of the western Brooks Range, Alaska. Previously, ...

"The geology of the northeastern Brooks Range does not match anything that we've studied in the neighboring region of North America," said Strauss, the research lead of the study.