Plate Tectonics on the Eminence Immersion

The picture of a convergent tectonic boundary pulls together our immersion trip to Eminence, and the geology we’ve been studying this quarter. We saw granite boulders at Elephant Rocks; climbed on a rhyolite outcrop near the Current River; spelunked through limestone/dolomitic caverns; and looked at sandstone and shale outcrops on the road to and from … Continue reading “Plate Tectonics on the Eminence Immersion”

Plate Tectonics and the Earthquake in Japan

The magnitude 8.9 earthquake that devastated coastal areas in Japan shows up very clearly on the United States Geologic Survey’s recent earthquake page. Based on our studies of plate tectonics, we can see why Japan is so prone to earthquakes, and we can also see why the earthquake occurred exactly where it did. View Larger … Continue reading “Plate Tectonics and the Earthquake in Japan”

Geothermal energy and plate tectonics

The question came up about where are good places for geothermal energy, and the answer, of course, was to introduce plate tectonics. It was a quick introduction, and a refresher for the 8th graders, but the interest was there and it seemed impactful. It also provided a link to talk about the Icelandic volcano that’s … Continue reading “Geothermal energy and plate tectonics”

Assessment with the Toilet Paper Timeline of Earth History

With a larger class, and quite a bit of space in the gym, I had more flexibility working on the toilet paper timeline compared to the last time. I built in a friendly race to see which group could find a set of events first, and allowed me to highlight nine different, important, series of … Continue reading “Assessment with the Toilet Paper Timeline of Earth History”

Inverse Relationships

Inverse relationships pop-up everywhere. They’re pretty common in physics (see Boyle’s Law for example: P ∝ 1/V), but there you sort-of expect them. You don’t quite expect to see them in the number of views of my blog posts, as are shown in the Popular Posts section of the column to the right. Table 1: … Continue reading “Inverse Relationships”

The Geology of St. Albans, Missouri

The area around the Fulton School has just two types of geology: young, floodplain sediments; and old limestone bedrock. Missouri River Flood Plain Sediments: The flat area next to the Missouri River that would get flooded regularly if the rivers weren’t regulated) Holocene (last 10,000 years) Clays and Silts (mud) deposited when the river floods. … Continue reading “The Geology of St. Albans, Missouri”

The Freezing Core Keeps the Earth Warm

The inner core of the Earth is made of solid metal, mostly iron. The outer core is also made of metal, but it’s liquid. Since it formed from the solar nebula, our planet has been cooling down, and the outer core has been freezing onto the inner core. Somewhat counter-intuitively, the freezing process is a … Continue reading “The Freezing Core Keeps the Earth Warm”

Tsunami Geometry: Calculating the Height of a Tsunami using Basic Geometry

Since we’re working on geometry this cycle, I thought it would be an interesting exercise to think about how we could use geometry to think about how the strength of tsunamis decreases with distance from the source. Of course, we’ll have to do this using some intense simplification so we can actually apply the tools … Continue reading “Tsunami Geometry: Calculating the Height of a Tsunami using Basic Geometry”