Between 65 And 145 Million Years Ago Which Of These Rivers Flowed Towards The Pacific Ocean?

 During the Late Cretaceous period, which occurred between 65 and 145 million years ago, the Earth was a very different place from what we see today. The continents were arranged differently, with a supercontinent called Pangaea having broken up and the land masses in the process of separating into the continents we know today. This period saw the evolution and diversification of many new species, including the dinosaurs, which dominated the terrestrial ecosystems.

One of the factors that influenced the ecology and distribution of life during the Late Cretaceous was the availability of water. Rivers were an important source of freshwater for many animals, including dinosaurs, and they also played a role in shaping the landscape and creating habitats for aquatic species. However, the specific rivers that existed during this time period are not well known, and much of the evidence has been lost to geologic processes such as erosion and plate tectonics.

Despite the challenges in studying ancient river systems, scientists have been able to make some educated guesses about the rivers that may have existed during the Late Cretaceous. This is done by studying the geology and sedimentary deposits of the time period, as well as the fossils of animals and plants that are associated with river environments.

One possible river that may have flowed towards the Pacific Ocean during the Late Cretaceous is the ancestral form of the Colorado River. The modern-day Colorado River is a major river that flows through several western states in the United States, including Arizona, California, and Nevada, before emptying into the Gulf of California. However, the Colorado River basin was not formed until after the Late Cretaceous, so any ancestral river that existed during this time period would have had a different course and drainage basin.

Another possible river that may have flowed towards the Pacific during the Late Cretaceous is the ancestral form of the Columbia River. The modern-day Columbia River is a large river that flows through the Pacific Northwest region of the United States and empties into the Pacific Ocean. The Columbia River basin was also not fully formed during the Late Cretaceous, but it is possible that an ancestral version of the river may have existed in some form during this time period.

The Sacramento River is another possible candidate for a river that may have flowed towards the Pacific during the Late Cretaceous. The modern-day Sacramento River is a major river in northern California that empties into the San Francisco Bay. Like the other rivers mentioned, the Sacramento River basin was not fully formed during the Late Cretaceous, but it is possible that an ancestral version of the river may have existed at that time.

While these rivers are possible candidates for rivers that may have flowed towards the Pacific during the Late Cretaceous, it is important to note that much of the evidence has been lost to geologic processes over time. Studying the geological history of the Earth during this time period is challenging, and scientists must rely on a variety of different sources of data to reconstruct what the world was like millions of years ago.

Despite these challenges, scientists continue to study the geologic history of the Earth in order to better understand the evolution and distribution of life during the Late Cretaceous and other periods of Earth's history. By piecing together the available evidence, they hope to gain a better understanding of the complex interplay between geology, climate, and life on Earth over time.