Recently, we've checked out posters about major extinction eras in our planet's history, plate tectonics, and geodsy ("the science of accurately measuring and understanding three fundamental properties of the Earth: its geometric shape, its orientation in space, and its gravity field— as well as the changes of these properties with time," definition per the National Ocean Service).
Today, we checked out a poster all about the rock types of the United States thanks to a poster from the American Geosciences Institute, which represents more than a quarter-million geoscientists.
One side of the poster featured a map of North America which was color-coded for geologic features of the land. Right away, the kids noticed that one of the colored categories of geologic types was plutonic rocks, and that they're plentiful in the Puget Sound region, where we live. They were pretty certain that the label didn't mean the ground in the areas was from Pluto, but we wanted to research the label.
We learned that characteristics of plutonic rock includes tightly packed mineral grains of medium size (1 to 5 millimeters), with the grains being of roughly equal size. All of the mineral matter is in a crystalline form, and plutonic rocks typically look like granite. The reason they have large mineral grains is because they cooled over tens of thousands of years, or longer, and that allowed the individual crystals to grow large.
Studying the map, the kids also noticed a wide swath of the middle of North America was labeled as being siliciclastic. We turned to Google to find out more about that, and quickly found a lecture (in PDF form) all about the classification of sedimentary rocks, including clastic (siliciclastic), with subcategories of sandstones, mudstones (shales), and conglomerates.
When we flipped the poster over, we saw a banner headline that read "Celebrate Geologic Map Day! Friday, October 16, 2015." That would be today!
One item the poster prominently mentioned was that 2015 is the bicentennial celebration of first nationwide geological map. How 'bout that?!
The amazing map was made by William 'Strata' Smith (23 March 1769 – 28 August 1839).
Smith worked for mining companies and over time, became to recognize the different strata in land that had been excavated, and he realized that the combinations of distinctive fossils within a rock can be used to identify it.
During his field work, Smith amassed an enormous and unique fossil collection, which he used as evidence to order his strata and make his maps. The Natural History Museum in the United Kingdom now has more than 2,000 of Smith’s fossils in their care.
Unfortunately, Smith's map was initially overlooked by the scientific community - and his work was frequently plagiarized. At one point, he was in such financial ruin, he spent time in a debtors' prison. Fortunately, Smith eventually received accolades for his work, and recognition for his accomplishments, and became known as the "Father of Geology".
You really should check out a big ol' image of Smith's history making map in this PDF from National History Museum in the United Kingdom.
http://www.nhm.ac.uk/content/dam/nhmwww/discover/first-geological-map-of-britain/william-smith-1815-geological-map.pdf
We are rather fond of the official title Smith gave to his map: 'A Delineation of the Strata of England and Wales, with Part of Scotland; Exhibiting the Collieries and Mines, the Marshes and Fen Lands Originally Overflowed by the Sea, and the Varieties of Soil According to the Variations in the Substrata, Illustrated by the Most Descriptive Names'.
Many things made the map remarkable, one being Smith's innovative use of color and shading to represent each rock layer. In all, he had twenty-three strata, meticulously hand-colored in different tints.
I was hoping to find a biographical video to show the kids about "Strata" Smith. Luckily, I landed on a great clip from the British Geological Survey, with an actor playing the Father of Geology.
https://youtu.be/CoUf1-_Lp54
HE'S NUMBER ONE: Last night, we had the good fortune of clear skies, allowing us to witness a fly over of the International Space Station.
This morning, one of the first emails I read let us know that today, ISS resident Scott Kelly has now broken the record for cumulative time in space by a U.S. astronaut.
Photo: NASA
As of today, over four missions, Kelly has spent 383 days off of the Earth, breaking the record of 382 days, previously held by Astronaut Mike Fincke.
Unfortunately, the clouds didn't allow us to see tonight's 8:18 ISS fly over. Hopefully Commander Kelly heard us chanting "You're Number One!" from our roofdeck.
Some other notable numbers: NASA astronaut Mike Lopez-Alegria has spent 215 consecutive days in space. Scott Kelly will break that record on Oct. 29. NASA astronaut Peggy Whitson has spent 377 total days in space. But neither of them are near Russian cosmonaut Gennady Padalka's 879 Days, the record for most cumulative days in space by any human.
This morning, one of the first emails I read let us know that today, ISS resident Scott Kelly has now broken the record for cumulative time in space by a U.S. astronaut.
As of today, over four missions, Kelly has spent 383 days off of the Earth, breaking the record of 382 days, previously held by Astronaut Mike Fincke.
Unfortunately, the clouds didn't allow us to see tonight's 8:18 ISS fly over. Hopefully Commander Kelly heard us chanting "You're Number One!" from our roofdeck.
Some other notable numbers: NASA astronaut Mike Lopez-Alegria has spent 215 consecutive days in space. Scott Kelly will break that record on Oct. 29. NASA astronaut Peggy Whitson has spent 377 total days in space. But neither of them are near Russian cosmonaut Gennady Padalka's 879 Days, the record for most cumulative days in space by any human.
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