Results: 1 - 3 of 3
Dec 31, 1957
Bulletin
… Lower Cenomanian substage of the Upper Cretaceous. Lithologic sections are … John area. The Lower Cretaceous-Upper Cretaceous boundary occurs at …
Dec 31, 1960
Bulletin
… basal sandstone member of the Upper Cretaceous Belly River formation. … eastward regression of the late Cretaceous Colorado sea. The …
Feb 28, 1946
Report
… to be underlain by non-marine Upper Cretaceous rocks in which coal …