{"thcode":2,"term":{"code":1634,"name":"geologic time periods","parent":1663,"scope":null},"uf":[{"name":"geologic age","usewith":false},{"name":"geologic time","usewith":false}],"bt":[{"code":1663,"name":"time periods","parent":1,"scope":"Geologic time periods and seasons of the year"},{"code":1,"name":"Categories","parent":null,"scope":"Thematic terms for categorizing information resources.  This thesaurus is intended to support finding and understanding scientific information."}],"nt":[{"code":1652,"name":"Phanerozoic","parent":1634,"scope":"Eon of geologic time approximately 542 million years ago extending to the present. https:\/\/doi.org\/10.3133\/fs20103059"},{"code":1655,"name":"Precambrian","parent":1634,"scope":"General interval of geologic time before approximately 542 million years ago. https:\/\/doi.org\/10.3133\/fs20103059"}],"rt":[]}