Thursday, April 28, 2011

Climate of the Cretaceous

During the late Cretaceous, Utah was around in the same place as it is today (meaning, same latitude, same longitude). That, however, does that mean that we had the same climate back then as we do today. The climate in Utah was hotter during this time because of increased volcanic activity, which released large amounts of carbon dioxide into the air. This increase in carbon dioxide upped the greenhouse effect back then, causing warming throughout the globe.

The warmer climate caused sea level to rise. Another process helped this as well. Ocean ridges are found on the seafloor at divergent boundaries where two plates are pulling away from each other and new crust is born. During the Cretaceous the plates were spreading extremely rapidly. This caused oceanic ridges to be elevated. When they do this they also push up the water, so the ocean water had to flow in somewhere and there happened to be a low ground right down the middle of the North American continent. Thus, half of Utah was under an arm of the ocean, and that arm would cover the interior of the U.S.

Unfortunately the ocean flooded out and the wet climate changed to dry, so we also had no beach to go swim in, but that doesn’t mean we didn’t have a good time. I think that my personal favorite thing that we did was the “Manual Labor." I had tons of fun digging through rocks and looking for clues. Sure, the first few hours proved fruitless, with me and Jessica finding only a few shells and one really ugly bug, but we knew that we were getting closer to our goal.

Once we started finding real bone things got exciting. I personally found two ribs, both of which were pretty “rotted out”, which basically means that they were in really bad shape. Scott Richardson marked them down on his chart and then wiped them away. We also found a really cool toe bone and one really strange looking bone that Scott was pretty sure was just another messed up rib but by the end of the day he still wasn’t 100% sure on what it was.

I had so much fun on this trip. I met many great people and I will always remember working on real dinosaur bones. I hope to return some day and help them on another dig site – and that time we’ll have to find to the skull. It’s right around the corner, I can feel it! ~Tauni

No comments: