Late Triassic Bivalve 'Monotis' in Accreted Terranes of Alaska

摘要

Late Triassic bivalves of the genus Monotis occur in at least 16 of thelithotectonic terranes and subterranes that together comprise nearly all of Alaska, and they also occur in the Upper Yukon region of Alaska where Triassic strata are regarded as representing non-accretionary North America. The purposes of this report are to enlarge upon these general conclusions and to provide needed documentation at a refined taxonomic level of the Monotis faunas presently known from Alaskan accreted terranes. Additionally, the authors hope that the illustrations, diagnoses, and identification key will enable Alaskan geologists to use this report as a field guide to the various species of Monotis.