00871cam a22002171  4500001001300000003000400013005001700017008004100034010001700075035001900092040002600111050002200137100005700159245022100216260004300437300004900480490004300529504003200572650002800604650002100632gs 25000068 DLC20260227111329.0830606s1925    dcua     b   f000 0 eng    ags 25000068   a(OCoLC)9580315  aDLCcMWalBdOrPSdDLC00aQE75b.B9 no. 7691 aWilmarth, M. Graceq(Mary Grace),d1866-1949,ecomp.14aThe geologic time classification of the United States Geological survey compared with other classifications, accompanied by the original definitions of era, period and epoch terms.cA compilation by M. Grace Wimarth.  aWashington,bGovt. print. off.,c1925.  avi, 138 p.bpl. (fold. tab.) tables.c23 cm.0 aU. S. Geological survey. Bulletinv769  aBibliographical references. 0aGeology, Stratigraphic. 0aGeological time.