Monday, July 15, 2013

Sed-head: Sedimentary Roxx

Maybe you know some things about rocks. Maybe you know *a lot* of things about rocks. You may have hear of rocks that form when über hot molten earth cools either below ground or spectacularly above ground. this happens in places like Hawai'i, where these brilliant scientists are scientifically examining 1000˚C-melt-your-face-off-hot lava from a conservative distance of 0ft. this kind of rock is called igneous. This class of rocks can form under or above the earth (intrusive versus extrusive) and have homogenous textures (example: fine grained basalts) or heterogeneous messy clumps of cemented-together crystals and scrapped off bits of the exit orifice (example: ignimbrite). 

The vast majority of igneous rocks form through this process.

Another, class of rocks form when other rocks under go a sort of metamorphosis. These are referred to as metamorphic rocks. Metamorphic rocks are like that cousin you have who used to try really had to be "cool," but just ended up looking like a douche-carnival scenster one weekend and then a preppy asshat surfer the next monday; metamorphic rocks are ~changed~ rocks that just want to be "cool" in the hipster thermodynamic sense. Because of the massive pressures and heats that some rocks, like many college students, face under the surface of the earth, certain minerals are more stable by becoming other minerals or by rearranging themselves in a more comfortable pattern. 

Sedimentary Rocks are the third class of rocks and really form the least thrilling group. While the other two classes of rocks can form under the earth, seds, begin their lives at the surface when either an igneous or metamorphic rock is exposed to the elements. The rock has weaknesses that allow ice, water, acid, or ground-shaking movements (earthquakes, landslides, your momma, etc.) to invade and weather it into small pieces called clasts. These pieces accumulate thanks to wind, water, gravity action into layers that become so heavy or get heated that they turn back into rocks. 

People don't make very good clasts. Too squishy.
A beautiful cross-section showing a slice of the "Baker's Quarry Formation". 

BELOW: A very complicated version of my blabber. Pretttttty skience.

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