Day 28: Who Needs Carbon Dating?

On the morning of July 5th, we woke up in Redding, California. This is not by itself particulary interesting, but it makes me happy because (a) Megan Rapinoe, midfielder for the US Women’s National Team, is from Redding, and (b) later that day, Rapinoe and her teammates won the World Cup. I like coincidences like that.

We left Redding pretty quickly and drove an hour west to Lassen Volcanic National Park. I had never heard of Lassen before we started planning our trip, so I wasn’t surprised to learn that it’s on lists of least-busy national parks, easiest national parks to camp in, national parks with no lines, etc. If it’s not on your list of places to visit, I strongly recommend you add it. It was everything that all those lists named and more. 

Lassen is, as the name suggests, an area of past volcanic activity. While it has this in common with Crater Lake, it also has a significant difference: you can see a lot of active geothermal features like you’d see in Yellowstone, but you can do it without the long lines and large crowds that Yellowstone has. For example, there was Cold Boiling Lake:

 

At around 110 degrees the water isn’t exactly cold, but it’s also not boiling. The bubbles are from gases escaping from beneath the lake, a subtle reminder that this is still an active volcanic area. There was also this: 

The yellow in this picture is sulfur stains from active vents and hot springs. As you can see, the sulfur has made it difficult for plants to grow in the area, so I find the single, small tree growing in the middle of the hill fascinating.  Here’s an active sulfur spring:   
 

It’s difficult to tell from the picture, but the gray, dirty-looking area at the bottom of the picture is a boiling sulfur spring (I suspect it’s not as cold as the lake). While it’s facsinating to see features like this up close, it’s also a little disturbing to see steam rising farther in the distance, a somewhat less subtle reminder of just how recently this area had a volcanic erruption.
  

The Lassen volcano last errupted just over 100 years ago, in May, 1915. Because of this there is a lot of photographic evidence of how the area was changed immediately after the eruption and how it has recovered over the past century. Given the relatively recent eruption, the park was able to include this display along a nature trail:

 Notice the three small rocks, one directly in front of the display and the similarly-sized ones on either side of it. These rocks are each 100 years old, having formed in the last eruption. This stands in stark contrast to two other rocks that are just out of the frame but are shown in the display in the picture; each of those rocks is approximately 17,000 years old.
I find this absolutely fascinating, but I am no more able to explain why than I am able to explain why waking up in Megan Rapinoe’s hometown on the day she won the Wold Cup makes me happy. Beyond my inexplicable interest in this, though, a question occurred to me: how often do we create misconceptions in our students by the examples we choose in class? When we teach exponential growth and decay, we talk about carbon dating to establish the dates of fossils. In doing so, do we leave our students with the false impression that all geological things are really, really old? 

What other misconceptions might we help form by what we choose to focus on? I am not claiming that we should stop teaching carbon dating, or be sure to talk about young rocks like these (although I probably will this year since it’s on my mind). I am just wondering what more substantial misconceptions we might unintentionally foster. I’ll add this to the long list of things to keep in mind as I’m presenting material, asking questions, and helping to develop our integrated math curriculum this year.

Advertisements

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s