James Hutton, the father of geology, put forth the principle of ________.

The only sequence to deposit sediment during the Cenozoic was the ________.

Based on the figure, what is the age of layer 7 relative to layer 3? 

Which statement best summarizes the development of the geologic time scale? 

Which of the following orogenies occurred in western North America? 

Who postulated the theory of inheritance of natural selection? 

Birds are believed to have evolved from ________.

An iridium-rich layer of clay, glass spherules, and shocked quartz grains strongly suggests that the K-T boundary extinctions were at least in part caused by ________.

Which of the following is a Cenozoic erosional feature of the Colorado Plateau (in North Arizona)?

Increased CO2 in the atmosphere results in ________