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NAL Agricultural Thesaurus

U.S. Department of Agriculture

Concept Breadcrumbs

Fields of Study > geology > geological eons > Precambrian time

Preferred Term:

Precambrian time

Definition:

The geological time from the formation of the Earth (4.55 billion years ago) to the start of the Cambrian period (about 570 million years ago).

Concept Schemes:

NALT Full

Broader Concept:

geological eons

Narrower Concepts:

URI:

https://lod.nal.usda.gov/nalt/290799

Download this Concept:

RDF/XMLCreated 2017-01-26, last modified 2017-11-10