GEOLOGICAL FORCES The poems on "Geological Forces" examine various forces that directly affect the surface of the planet. 1:GEOLOGISTS A geologist studies the materials that make up the earth. They’re trying to figure out what’s been happening since earth’s primordial(1) birth. The materials don’t talk or write so they use indirect evidence(2). It’s tricky stuff and depends much on repetition and common sense. Like they say the earth has a core, mantle and crust, kind of like an egg. Yet, how can geologists know this I must urgently beg? Well, they bounce seismic waves through the crust and mantle to the earth’s core, And look for consistent patterns and echoes, if not sure they’ll bounce still more. They know that waves behave differently as they bounce off materials of differing density, Struggling to understand, using echoes and wave patterns, the Earth’s inner ferocity. Convection currents, lithosphere, aethenosphere; scientists use many a big word. Allow me to define these big words, just in case you haven’t heard. The lithosphere is the rigid layer of the mantle and the earth’s crust While the aethenosphere is the soft layer beneath the lithosphere and will always push and thrust For the heat of the core causes convection currents in the upper mantle, not by choice but because it must, Because of differing densities of matter that varies between hot and cold, Working on a grand scale, like soup warmed on a stove I’ve been told. As the mantle near the hot core begins to heat up and rise, It pushes away the upper, cooler layers, which then sink to no surprise. This part of the mantle is then heated up and the process continues ever more. Say what you want about geology, but admit that it is never, ever a bore!   1: Primordial-The very beginning of creation. 2: Indirect Evidence-Evidence gathered that was not directly seen by an eyewitness. When a detective tries to solve a crime, they are often using indirect evidence. Since no one has seen the inside of the Earth, scientists have no choice but to use indirect evidence to attempt an understanding on how the Earth came to be.

An illustration of how water erosion works.

Study this illustration before proceeding to poem.

King's Canyon National Park

Lots of erosion going on here!

2: WEATHERING, EROSION AND DEPOSITION Weathering, erosion and deposition all change the earth. Indeed, its been going on since the earth’s very birth. Weathering comprises of all the forces that break things down, While erosion includes the forces that move this stuff around And deposition is when this eroded stuff finally lands on the solid ground. Constructive and destructive forces are always changing the land. And, by the way, I don’t just mean soft stuff like fine and silky sand Constructive forces build matter up while destructive forces wear matter away, Examples are wind, moving water, gravity, volcanoes, waves, and tides and come what may. Given enough time, the mightiest mountain will wear down, And, yes, even you are not forever, but there's no need to frown, For from one form to another does matter always change. Thank heavens, for this is how you came onto the range.

Glacial erosion at work.

Glaciers move slowly but their affect on the landscape is powerful.

Glacier National Park.

An example of glacial erosion.

3: GLACIERS A glacier is basically a moving block of ice, Sculpturing the landscape in ways both rough and concise. Glaciers usually form in high mountain country Where weather leans more towards the blustery wintry. Huge glaciers also form in cold places like Greenland, Spreading like pancake batter on a cold frying pan. How does this mighty block of ice form you are bound to say? Well, for starters, it needs to snow quite a lot and be cold throughout the day. As the snow accumulates, its weight begins to squeeze down, And this squeezing down turns snow to ice by the kilo pound. Over many years, you’ll have a block of ice with a great and fearsome might, Changing the landscape throughout the day and the pitch-black night. As the glacier slowly moves, it picks up a lot of sediment and rock, Cutting, scraping and grinding the land in ways to make you gawk. Making the land beautiful and giving it awesome majesty, And from the air, it takes the look of a complex tapestry,

An illustration of different types of volcanoes.

Notice that most volcanoes fall into three categories.

4: Volcanoes: A volcano is basically an opening in the Earth’s crust. When gas builds up in the underground magma, upward will it thrust, For these gases build up pressure in the magma chamber(5) deep underground, As these gases are released, nature will thunder a most ominous sound. The magma is forced up the volcano’s pipe with remarkable and awesome might. Now the lava flow begins, creating floods, mudflows and other tales of fright. How thick the lava will be is determined by its temperature and silica(6) content. Higher the temperature and lower the silica amount; thinner lava will nature vent. Thicker lava will be more chunky with much trapped gas inside. It’s quite a bit more unpredictable I will to you earnestly confide. Magma can also rise when it is squeezed or is less dense than surrounding material inside the earth. These natural processes have been shaping the landscape of the earth since its primordial birth. The earth has an explosive heart and may rest but will never sleep. Scientists will never completely understand her secrets which are found so very deep. 5: Magma Chamber-A large reservoir in the crust of the earth that is occupied by a body of magma. 6: Silica-Naturally occurring silicon dioxide. (SiO2) It is a glasslike compound.

Some examples of mechanical weathering.

What's the difference between mechanical and chemical weathering?

5: Weathering and Life: Mechanical(7) and chemical weathering(8) slowly break down almost every thing. This process of destruction and renewal does much benefit to us bring, For it is the process of death and renewal which gave life its first tenuous hold, Which eventually evolved into the eyes and ears of the universe will I venture forth so bold. Soil, which grows our food, is a mixture of eroded rock and decayed organic matter. If weathering didn’t take place, they’d be no food for us humans, not even a tatter. Our moon doesn’t change very much because the geological forces to make it happen aren’t in place, Which brings forth the question of whether a cosmic body without life is to us a total waste? As one who loves to look at the stars and the moon, I say these creations are an awesome mystery, Whose creation was necessary to create the Earth, which has its own unique and fascinating history.   7: Mechanical Weathering-The breaking down of a substance through physical forces. If you break apart a rock with a hammer, that is an example of mechanical weathering. 8: Chemical Weathering-The breaking down of a substance through chemical forces. When plants secrete a slightly acidic acid that breaks down rock, this would be an example of chemical weathering.

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