So How Did They Get There?

        What first intrigued me about the Great Sand Dunes, was the fact that they seemed so out of place. Like I explained in my previous post, it just didn’t seem like the dunes belonged in the middle of the Rocky Mountains. Now that I am becoming slightly more familiar with geographical processes, there is more explanation as to why these seemingly random land forms exist. What I learned is that there are actually two different mountain ranges that surround the dunes. One is called the Sangre de Cristo mountain range and the other is the San Juan Mountain Range. These mountain ranges exist because the process of moving plates within the Earth’s surface. This is what we call plate tectonics. The specific plate process that created the mountain ranges is convergence, where the plates came together and the Earth’s surface came up and together to create the mountains. Between the ranges is what we call a valley which is the flat land between the mountain ranges. This valley is where the actual dunes are located. As we all know the dunes are formed from sand which was blown into the valley by wind. Specifically the type of rock that makes up each dune is sandstone which is a classic sedimentary rock. Now I know a little further as to why the dunes are there and about what the dunes are made up of specifically.