Category Archives: Geology

Misconception – Crust and Lithosphere are the Same Thing

There are many misconceptions about geological concepts. There is a list here, developed by Kent Kirby of the University of Minnesota. This post is to debunk one of those misconceptions. There will be others. Find them here.

Misconception: Crust and Lithosphere (or plates) are synonymous termsContinue reading “Misconception – Crust and Lithosphere are the Same Thing”

Cleavage … and Fracture

Did that catch your eye?

Yes, this is a geology post. I’m thinking about cleavage because it came up in class today. I would really like to do a demonstration of cleavage by smashing a calcite crystal to bits in front of the class. Don’t think that’s going to happen, alas.

But since I was thinking about it, I thought I’d write about it. So…Continue reading “Cleavage … and Fracture”

The Size and Age of the Universe

As I prepare for my fourth semester of teaching introductory geology, I remember that the first couple of lectures usually throw me. I decided to prepare in advance for the moments I look at my notes and have no idea where I was going.

Yes, kids, it happens. I am not an expert in everything that might ought to be covered in an introductory geology classes. Sometimes I get flummoxed when I’m lecturing about things that are not within my realm of expertise.Continue reading “The Size and Age of the Universe”

Color – Part Three – Rock Formations

Earlier this week, I explained how color can be quantified and how the use of color might be used to examine orbital cycles in ancient rocks.

Here, I’ll describe another potential application. In this case, we’d like to be able to better define the boundary between the older Uinta Formation and the overlying Duchesne River Formation. (As an aside, Duchesne is pronounced Doo-shayne.)Continue reading “Color – Part Three – Rock Formations”

Color – Part Two – The Hanna Formation

So, now that I’ve explained color in yesterday’s post, let’s see what some geological data look like.

These are ugly graphs of raw data constructed in Excel. I wouldn’t publish these, but we can use them to visualize the data at a first pass.

Let’s start in the Hanna Basin. This summer, my field assistant and I measured the rock thickness and took color measurements with the RM200QC in a critical part of the Hanna Formation that most likely includes the Paleocene-Eocene boundary (55 million years ago). You can see the travelogues for those days in the field here and here.Continue reading “Color – Part Two – The Hanna Formation”