Penny Higgins - Storyteller • Artist • Scientist
Combining Science and Joyful Creativity
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:
Continue reading “Strike and Dip – It’s Not A Dance Craze (But It Should Be!)”
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.
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”
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”
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”
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.
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”
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”
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. There will be others. Find them here.
Misconception: Streams are simply flowing water
Misconception: Rivers do not carve valleys, but only passively flow down them
Misconception: Although rivers can cut down over time, they do not cut to the sidesContinue reading “Misconceptions – Rivers Flow Passively over the Surface of the Earth”
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: Rivers flow south – sometimes modified to rivers in northern hemisphere flow south, while those in southern hemisphere flow northContinue reading “Misconception – Rivers Flow South”
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: Earth’s core is hollow, or that large hollow spaces occur deep within EarthContinue reading “Misconception – The Earth’s core is hollow, or that large hollow spaces occur deep within Earth”
Penny Higgins - Storyteller • Artist • Scientist