Eonothems are not often used in practice as expert dating estimates can be and usually are specified into the more refined timelines of smaller chronostratigraphic units the smallest units used in dating .
Smaller chronostratigraphic units can be subdivided in turn down to the many defined stages .
Eonothems are not often used in practice as expert dating estimates can be and usually are specified into the more refined timelines of smaller chronostratigraphic units , which can be subdivided in turn down to the many defined stages , the smallest units used in dating .