Category Archives: Geology

If I Were a Mineral, Would You Rock My World?

Every science – actually every discipline any person can study – has some fundamental basics that are absolutely important.

You can’t study language without knowing the difference between a noun and a verb (and how that works with adjectives and adverbs).  You can’t study biology without knowing what a species is. And you can’t understand geology without knowing what the difference between a rock and a mineral is.

In teaching an introductory geology class, you might guess I spend quite a bit of time discussing the latter. I always think it should be obvious. But the only obvious thing is that it isn’t obvious.Continue reading “If I Were a Mineral, Would You Rock My World?”

Strike and Dip – It’s Not A Dance Craze (But It Should Be!)

Sedimentary rocks, those made of little crumbled bits of pre-existing rocks, are all originally deposited in horizontal layers (or very close to it). This is one of the most important principles in understanding how to assign ages to rocks.

The problem is, that most rock layers that we see are anything but perfectly horizontal. Take a look at this, for example:

Siccar Point. Credit: Dave Sousa CC 3.0 By-SA

Continue reading “Strike and Dip – It’s Not A Dance Craze (But It Should Be!)”

Cross Bedding and Finding Up

Sometimes, I have a terrible time explaining something to my students in class.

Sometimes, I can redeem myself by writing a blog post clearly explaining what I couldn’t get through in class.

One of those topics is cross-bedding in rocks. Now, if you’ve ever driven anywhere in the southwestern United States, you’ve seen lots of cross-bedding.

Crossbedding of sandstone near Mt. Carmel road, Zion Canyon, indicating wind action and sand dune formation prior to formation of rock. Credit: National Park Service photo by George A. Grant, 1929

This can happen at nearly any scale, from tens of feet in thickness, to inches in thickness. So, then, how do cross beds form?Continue reading “Cross Bedding and Finding Up”

Can Science Support Creationism?

Today, I’m giving at talk for RIT Skeptics with the above title. This post is the analogue version of the presentation for those who cannot attend. It’s also a good way for me to organize my thoughts in a linear fashion.

The point of the talk is to show whether or not some ideas of ‘Special Creation’ can be supported by science. Specifically, I’ll compare the Theory of Evolution with concepts of Intelligent Design and Scientific Creationism.Continue reading “Can Science Support Creationism?”

How Geology Has Benefited from the Military

Today is Veteran’s Day in the United States, a day in which we thank all members of our armed forces, past, present, and future, living or deceased, for their service in protecting our nation and keeping it strong.

I could write a kitchy post about how thankful I am (and I am, believe me. My father retired a full-bird Colonel from the United States Army), but instead I though I’d write about how the science of geology has benefited from the needs of the military.Continue reading “How Geology Has Benefited from the Military”

Misconceptions About How Glaciers Move

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 a few of those misconceptions, specifically dealing with how glaciers work. There will be others. Find them here.Continue reading “Misconceptions About How Glaciers Move”

Pangaea, Rodinia, and Their Oceans

I was asked a question via Twitter the other day that I thought warranted its own blog post.

The question was in regard past supercontinents, like Pangaea, which existed during the time of the dinosaurs (forming about 300 million years ago and lasting until about 70 million years ago), and the much-older Rodinia (existing between 1.1 billion and 750 million years ago). At these times (and probably other, even earlier times) all of the Earth’s major continents were combined into one huge continent.

The supercontinent of Pangaea, with the modern continents’ positions within the landmass outlined. Credit: Keiff CC 3.0 sa

Continue reading “Pangaea, Rodinia, and Their Oceans”

No Really, Not All Rivers Flow South – Niagara Falls

This is a little mini-rant. Remember this post from last week, in which I explain that rivers can, in fact, flow north? I was working on a little post for today describing the concept of knickpoints and rivers. It turns out Niagara Falls is a great example of this.

It turns out also that most likely all the satellite views of Niagara Falls you’ve seen on the Internet are oriented wrong.Continue reading “No Really, Not All Rivers Flow South – Niagara Falls”

Misconception – Waterfalls can get taller, but they don’t retreat

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 one of those misconceptions. There will be others. Find them here.

Misconception: Waterfalls can increase in height over time, but do not retreatContinue reading “Misconception – Waterfalls can get taller, but they don’t retreat”