The San Franciscan Volcanic Field, Arizona (open access)

The San Franciscan Volcanic Field, Arizona

Introduction: This report deals primarily with the volcanic phenomena of the region as determined in the field and laboratory.
Date: 1913
Creator: Robinson, Henry Hollister
System: The UNT Digital Library
Recurrent Tropidoleptus Zones of the Upper Devonian in New York (open access)

Recurrent Tropidoleptus Zones of the Upper Devonian in New York

From introduction: This report describes the four zones, three well-marked and one subordinate, in the Upper Devonian rocks, each of which contained several species that are common in the typical Hamilton formation of the Cayuga Lake section and are associated with very few of the really characteristic species of the faunas normal to the formations in which they are found.
Date: 1913
Creator: Williams, Henry Shaler
System: The UNT Digital Library