Monday, April 28, 2008
I did some driving today through the Columbia River Gorge and around Mount Hood, and I wanted to share with you some really cool geology from the area.
First of all, I should probably provide some background. The Columbia River Gorge has been (after all, it is still being formed) formed through a series of events that have occurred to give it its current configuration. This configuration was especially important for the Oregon Trail, but that’s a whole different post.
Anyway, between 17 and 12 million years ago, the Columbia River plateau formed from a series of flood basalt flows. These flows were unlike anything we see today. The area covered by these flows (similar flows occurred in the Deccan Traps) includes portions of today’s Washington, Oregon, and Idaho - to the tune of 164,000 square kilometers. As these basalt flows (think the same kind of rock found in the Hawai’ian islands) cooled, the rocks cracked, forming columnar basalts. I was able to see these columnar basalts when I visited several waterfalls along the gorge.
Since then, the area witnessed the birth of the Cascade Mountain range. Unlike other mountain ranges such as the Sierra Nevadas or the Appalachian Mountains, the Cascade Range consists of a series of volcanoes. Among these volcanoes are the infamous Mount St. Helens, Mount Rainier, and Mount Hood. Because of their proximity to subducting tectonic plates, these volcanoes erupt with a siliceous magma that is very viscous (hard to flow). These rocks form a special kind of volcanic rock called andesite, and can be seen not only throughout the Cascades, but also the Andes (hence the name - ande-site). Today, as I circled around Mount Hood, I came across some of those andesites.
At the same time the Cascades were forming, the entire area has undergone a tectonic uplift, raising the continental crust. The action from the mighty Columbia River has served to form what is now known as the Columbia River Gorge. It’s the same kind of process that has helped form the Grand Canyon. As the continental crust raises, the river’s force has scoured out the landscape as it makes its way to the ocean. Because the area rose so rapidly (in geologic times, mind you), the river gouged out a narrow passageway instead of meandering its way across the land. To picture the difference between the two processes, think of a comparison between the Grand Canyon and the Mississippi River delta. One is deep and narrow, one is wide and flat.
Well folks, there you have it. Geology 101 from the Cascades. I hope the next time you step out your front door, think of all the things that had to take place in the past to shape the land to its current configuration!
Friday, April 25, 2008
Here is more information on the "Atmosphere: Change is in the Air" website:
Explore Earth’s changing atmosphere. Discover how our ever-changing atmosphere transports substances around the globe, protects life from destruction, and supports millions of chemical reactions. Find out how scientists track changes in the atmosphere and why they matter to everything that breathes.
This web site incorporates images and information from the Atmosphere: Change is in the Air exhibition developed by the Smithsonian’s National Museum of Natural History, which was on display at the Museum through November 2006. The exhibition explores the chemistry, properties, and significance of earth’s atmosphere—the invisible envelope that surrounds and affects us all.
Tuesday, April 15, 2008
Then there are days where I'm reminded of how much I love what I do, and how cool and very utterly exciting all of it is.
Today started like that first description. Scratch that - the past week has been like that first description. As I sat down to write this blog entry, however, today became one of those days that's like the second description. I was instantly reminded of why I got into this buisness in the first place:
Science + New ways to view the world = Awesomeness
The variables in the above equation can be substituted with just about any kind of scientific pursuit, such as it is in the title of this blog entry.
What in the world am I talking about, you might ask? It's simple. Take one constantly erupting volcano, add in some high-tech observations from 705 km (438 miles) above the Earth, and presto! Instant awesomeness.
Kilauea volcano has been making the news rounds lately because it started erupting from the main caldera in March. (You can find out information about the eruption here). According to the Associated Press, prior to the March eruptions, Kilauea's caldera hadn't erupted since 1924. Back then, the best scientific data we could get about volcanic gases came from a view rare souls who were brave enough to get as close as they dared. Flash forward to the present. Now, the Ozone Monitoring Instrument (OMI) aboard the Aura spacecraft has been taking daily data on the SO2 emissions from Halema 'uma 'u vent. These data show the enormous amout of SO2 that is spewing from the vent, and give us that information on a daily basis.
Like I said, one of the reasons why I love what I do.
The images on this page show 1. Kilauea from the ground and from 2. Aura's OMI instrument.
OMI SO2 measurements
Earth Observatory article on OMI SO2 and Kilauea
Thursday, April 3, 2008
Check out the Yuri's Night 2008 website for more information on festivities, tickets, directions, etc. Hope to see you all there!