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GY140 – Physical Geology

What can rocks tell us about the earth's history?

Mosquito Range near Fairplay, Colorado. Photo by Becky Zentmyer '05.
Mosquito Range near Fairplay, Colorado. Photo by Becky Zentmyer '05.


Professor Eric Leonard email

GY 140 is a one-block course that introduces the fundamentals of geoscience using the Rocky Mountain and Colorado Plateau settings as a natural laboratory. We will investigate the record of the Earth’s history preserved in the rocks and the dynamic geologic processes active in the mountain and desert environments. We will also focus on how human activities are affected by and affect these processes.

We will (weather cooperating) spend more than half of our class time in the field, on trips ranging from a half-day to five-days length. The field trips will be project oriented and are probably the most important part of the class. We will be camping out all of the third week of the block, so you will need to be prepared, physically and psychologically, for the vagaries of Colorado weather (this holds for our other trips as well).

Our goal is that by the end of the class you will be able to “read the landscape” in the Rocky Mountain West and elsewhere. Whether this class is a first step towards a Geology major or your only venture into the earth sciences, we hope that you will carry away from it an appreciation of how this region has been shaped by geological processes and how those processes influence its human inhabitants.

About the Instructors

I suppose that my interest in geology grew from backpack/climbing trips I took into the California Sierra Nevada as a teenager – scrambling over talus and glacial deposits (although I didn’t know what they were at the time), and jumping across meandering and braided streams. Or maybe it came even earlier from growing up in San Francisco about 10 miles from the San Andreas Fault. In any case, my own meandering course from an undergraduate European History major and a master’s degree in Geography, to a PhD in Geological Sciences, eventually brought me to the CC Geology Department. My professional work in Geology, besides teaching, involves studies of past glaciation and climate change and attempts to understand how landforms and structures at the surface of the earth reflect what is happening deep inside the earth. I am also very interested in how geologic processes affect humans and how humans affect geologic processes. Mainly though, I just love trying to figure out how the earth works … and walking through the mountains or the desert, soaking it all in, is a great fringe benefit! — Professor Eric Leonard

My name is Wesley Paulson. I graduated from CC as a Geology major last year, and have spent the current year as paraprof in the Geology Department. The Plate Tectonics class I took my sophomore year was what sparked my interest in geology. We took a field trip to Kilbourne Hole, a volcanic crater in New Mexico about 15 miles from the Mexican border. We spent the day collecting xenoliths – chunks of the Earth’s mantle and the continental crust that have been ripped off from the surrounding “country” rock into the magma chamber and encrusted in magma, before being erupted at the surface. After we had time to go around and collect samples, the class gathered together and put the xenoliths in order, starting with the ones that formed deepest beneath the surface. This exercise, which gave the opportunity to visualize what rock types lie deep in the Earth, in places that humans have never been, fascinated me. For me, this provides a great example of how geology can give us an understanding of, and an appreciation for, many different processes that have occurred, and are occurring, on Earth. — Wesley Paulson

Prerequisite: No credit after GY 130