Rising or falling sea level can be initiated by global climate change or tectonic events like mountain building. During cold periods, like ice ages, more of the world’s water is stored in continental glaciers (e. g., Greenland), causing sea-level fall. As the planet warms and the ice melts, sea level then rises. Tectonic processes create mountains and adjacent inland depressions (basins) that in turn collect water and sediments transported from the highlands. During the formation of the Canadian Rockies, a seaway formed between the Rockies and the continental interior of the United States and Canada. This waterway, called the Cretaceous Interior Seaway, existed ~145 to 66 million years ago and spanned from the present-day Gulf of Mexico north through western Canada. Some of the sediment deposited at the base of this sea eroded from the Canadian Rockies. Mountain topography is created by tectonic processes that deform and uplift rock. However, its form is highly dependent on the various processes that erode it. For example, hillslopes can erode by landslides, rivers, soil creep, or even glaciers; each process leaves its unique signature.
a. Rainwater once flowed from the Canadian Rockies into the Cretaceous Interior Seaway.
b. Stromatolites are the geologic evidence that indicates that this region was tectonically active.
c. There is no evidence of tectonic activity in the Gigapan image.
d. There is evidence that the location shown in the Gigapan image once was near a shoreline.
e. The mean annual temperature of the location shown in the Gigapan image was once much lower than it is today.