Preliminary report on early Tertiary clastics, west-central Yukon

Examination of Early Tertiary clastic rocks in the Indian and Sixty Mile River areas has revealed that: 1) sediments are arranged in fining-upward sequences and are dominated by sandstone and to a lesser extent conglomerate; 2) the clastic sequence in the Indian River area is thicker than previously thought; and 3) conglomerate beds consist mainly of white vein quartz, Nasina Quartzite, Klondike Schist and chert pebbles. The metamorphic clasts were probably locally derived and the chert pebbles were eroded from the Ogilvie Mountains. These clastic rocks are interpreted as being deposited in separate, but coeval, continental basins that were mainly fed by southward flowing braided-rivers.