Nature's Birth
The earth has a history just as every living, breathing thing on her does. Let's take a brief, yet closer, scientific look at how it all began by taking a trip back through time.
CENOZOIC ERA
- Quarternary Period (aka Neogene Period) -
modern man appears; began 2 million years ago.
- Tertiary Period (aka Paleogene Period) -
large carnivores appear; large grazing animals appear; began 65 million years ago.
MESOZOIC ERA
- Cretaceous Period -
flowering plants appear; began 135 million years ago.
- Jurassic Period -
birds appear; began 190 million years ago.
- Triassic Period -
mammals appear; formation of Atlantic ocean begins; dinosaurs appear; began 225 million years ago.
PALEOZOIC ERA
- Permiam Period -
began 280 million years ago.
- Carboniferous Period -
reptiles appear; great swamp forests at peak; began 360 million years ago.
- Devonian Period -
ferns appear; forests develop; began 395 million years ago.
- Silurian Period -
amphibians appear; land plants appear; began 430 million years ago.
- Ordovician Period -
formation of Appalachian Mountains begins; began 500 million years ago.
- Cambrian Period -
fish appear; began 570 million years ago.
PRECAMBRIAN ERA
- Proterozoic Period -
multicellular organisms appear; began 1,500 million years ago; blue-green algea appears; began 2,500 million years ago; bacteria appears; began 3,500 million years ago.
- Acheozoic Period -
formation of the earth; began 4,600 million years ago.
Earth Stats
- Diameter - The
average diameter is 7,918 miles, the equator diameter is 7,926 miles and the poles diameter is 7,900 miles.
- Circumference -
The distance around the equator is 249,000 miles.
- Surface Area - The
area of the earth's surface is approimately 197,000,000 square miles of which 30% is land.
- Density - The average density of the earth is 344.4 pounds per cubic foot, or about 5.5 times the density of water.
- Weight - The total weight of the earth is estimated at 6.6 X 10(21) tons, or 6,600 billion billion tons.
- Structure - The
earth consist of 3 parts:
- The Crust - rigid
outer portion; thickness ranges from less than 6 to 25 miles; composed mainly of granite (under the continents) followed by denser rock (chiefly basalt); crust under ocean is almost entirely basalt covered by thick layers of sediment; average density of crust is 3.0 times that of water.
- The Mantle - approximately
1,800 miles thick; usually consist of the mineral olivine (a silacate of magnesium and iron); average density is 5.5 times that of water.
- The Core - believed
to consist of iron alloyed with small amounts of nickle and one or more lighter elements such as oxygen, silicon, and sulfur. The Core is broken into 2 parts: the liquid Outer Core is approximately 1,300 miles; average density is 11 times that of water; the solid Inner Core diameter is approximatly 1,660 miles; average density is 12.5 times that of water.
Little-known Facts of Nature
Did you know there have been several ice ages? These have been reported as being severe winters due to their small size and shortness. Remember the two Blizzards of 1888? In January of 1888, 220 people were believed to have died when a blizzard raged across the Great Plains from the Dakotas to Texas. In March of 1888, more than 400 people were reported as killed when a blizzard swept through the northeastern United States with paralyzing drifts of upto 30 feet. These blizzards are perfect examples of a small, short ice age, but there have been many more.
Did you know that a 1 degree shift in the earth's axis would alter the weather quite drastically? For example, if the earth shifted north (away from the sun) that the winters in North Carolina would be equal to those currently in Pennsylvania, whereas a shift to the south (toward the sun) would make the winters in Pennsylvania equal to those currently in North Carolina. Imagine what the rest of the world would feel if this tiny axis shift happened. Now what if the axis shift were 10 degrees?
Did you know that only 2.8% of the Earth's water supply is fresh water?
California isn't the only state that needs to worry about 'earthly vibrations'. In late October or early November 1997, on a calm Thursday morning at about 3:00 AM, a 3.9 earthquake rattled windows. The longitude was 31.17 N and the latitude was 87.25 W, placing it just north of a small city called Fort Walton Beach, Florida. Later in the morning, the earthquake was upgraded to a 4.3.
Did you know there has always been a hole in the ozone layer? This small 'vent hole' over Antartica is there for two resons:
- the lack of animal and plant life doesn't allow the hole to repair itself
- Nature naturally produces gases (carbon monoxide, methane and a few others) and this vent hole allows these gases to escape into space
where they are harmless.
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