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Question 33240

Brandon
Featured 3 months ago

Explanation:

The mantle is between the core and crust of the earth. It makes up around 80% of the earth's atmosphere and around 17% of the earth's volume. It is around 2.900km thickness and is made from magma.

It is located between the core and the crust.

See picture below:

http://www.bbc.co.uk/schools/gcsebitesize/geography/natural_hazards/tectonic_plates_rev1.shtml

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Which fossil type provides the most anatomical to paleontologists?

Charlie P.
Featured 3 months ago

Something that has been mummified, for example a Woolly Mammoth in permafrost or anything organic in the most closest form of something in suspended animation.

Explanation:

A fossil is something that has been preserved, whether it be in an imprint in a rock like a foot print, or it be an arrowhead lying at the back of a cave where early man once dwelled. It is something that has been preserved that we can learn something from, whether it be valuable or invaluable.

I would propose something, that is mummified, which is something that is deceased and has had all of its biological details preserved to the extent that it looks how it would of been when it died.

*The well preserved baby Woolly Mammoth that was discovered by a reindeer herder *

Animals or even plants, which were frozen in permafrost, amber, peat or tar, are some of the best preserved specimens we have to date, which were not preserved by human action, such as when we put an organism in preservation alcohol or formaldehyde.

Examples of specimens preserved/mummified by the use of spirits, which have been 'pickled'

We learn so much from these types of preservation due to the fact that the organic material on the body does not decompose, due to the microorganisms having either no heat in the case of permafrost, oxygen in amber or peat, or moisture (and lack of sunlight) at the back of an arid cave, this is why many scientists are excited about the fact we could soon start cloning these creatures again, due to the fact their genome/DNA is close to complete.

A plant that was cloned from the fruit of the narrowed-leafed campion over 32,000 years ago, that was preserved in permafrost

We can also study these creatures a lot better, due to the fact that many which have been preserved by these natural methods have little or no bacteria on their bodies as they have come inhospitable for them, this is called desiccation, however for some frozen specimens, desiccation does not work so well for.

We must however, at the end of the day think about what we learn from something that is fossilised this way or anyway. You can learn a lot from an organism that has desiccated such as its organs and biology, but you cannot learn for example its behaviour or migratory routes from just one of these specimens, this is why all fossils help to build up the picture for paleontologists alike about what the past was like.

Hope this helps
-Charlie!

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How does tectonic plate movement change the earth?

JJ
Featured 3 months ago

Many ways.

Explanation:

First of all, tectonic plates are always moving, even if we may not feel them. This movement causes many things to happen, and change the earth.

Cracks in the earth are sometimes formed from this movement. The continents slowly move, and sometimes, they can start to break apart. Now, this doesn't just happen in 20 years. It take millions of years, so no need to worry about the earth opening up and you falling into a pit of magma. A couple years ago, an ice shelf was found in Antarctica from this movement.

Volcanos are also created from the tectonic plates moving. When two plates are moving, and they hit each other, one will slowly be pushed down beneath the other, and create a volcano.

Those are just a few examples of how tectonic plate movement can change the earth, there are many more. Here are some related questions showing how this movement shapes the earth:

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How does gravity work with water ice and wind to cause erosion?

JJ
Featured 3 months ago

See below

Explanation:

Gravity works with water, ice, and wind to cause erosion in many ways.

color(blue)(Water: Gravity works with water to cause erosion from waves. The gravity pulls the water with the combinated force of the wind to hit rocks or cliffs, and with every hit, a layer of rock or dirt comes off. Big or small, this layer still comes off, eating away at the rock until it is degraded to nothing.

color(gray)(Ice: Gravity works with ice because as the gravity pulls the ice, the bottom grinds on the ground below it.

Wind: Gravity works with wind because wind blown hail, snow, or sleet can hit rocks with a great force, eroding them.

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What makes a solar eclipse? Thank you!

Gazza
Featured 3 months ago

See details bellow....

Explanation:

A solar eclipse occurs when the moon moves in a line directly between earth and the sun, casting a shadow on earth. This produces a solar eclipse. This situation occurs during new-moon phases. The moon is eclipsed when it moves within Earth’s shadow, producing a lunar eclipse. This situation occurs during full- moon phases.

During a total solar eclipse, the moon casts a circular shadow that is never wider than 275 kilometers, about the length of South Carolina. Anyone observing in this region will see the moon slowly block the sun from view and the sky darken. When the eclipse is almost com- plete, the temperature sharply drops a few degrees. The solar disk is completely blocked for seven minutes at the most. This happens because the moon’s shadow is so small. Then one edge of the solar disk reappears.

When the eclipse is complete, the dark moon is seen covering the complete solar disk. Only the sun’s brilliant white outer atmosphere is visible. Total solar eclipses are visible only to people in the dark part of the moon’s shadow known as the umbra. A partial eclipse is seen by those in the light portion of the shadow, known as the penumbra.

A total solar eclipse is a rare event at any location. The next one that will be visible from the United States will take place on August 21, 2017. It will sweep southeast across the country from Oregon to South Carolina.

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What are the three volcanic hazards that must have been associated with the eruption that devastated Santorini?

David Drayer
Featured 2 months ago

tsunami , earthquakes and volcanic dust.

Explanation:

The island that had been Santorini exploded leaving just a broken ring of rocks outlining the circle of the volcanic cone.

The ash plume that was created by the explosion of an entire island would have blanketed the surrounding area. The dust would have destroyed crops changed the climate for a time, and caused havoc with travel, health, and commerce.

The earthquakes created by the massive explosion are thought to have destroyed the palace culture of Crete. The earthquakes would have caused damage throughout the area.

The earthquakes would also create huge earthquake water waves, known as Tsunami. These powerful fast moving waves would have spread out in all directions from the ruined island causing damage wherever the waves made landfall.

Ash, earthquakes, tsunami would all have created damage as part of the hazards of the volcanic eruption.

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How are mid-ocean ridges and deep-ocean trenches related to plate tectonics?

Hannah M.
Featured 2 months ago

Under-water trenches and ridges are created by plate tectonics.

Explanation:

The crust of the earth is covered with Oceanic and Continental plates. These plates are moving constantly but are moving very very slowly. They move because of something called convection currents. Convection currents push these plates together and apart. Convection currents are created by rising and falling heat in the earth's mantle.

When two oceanic plates are pushed away from each other, magma rises to the surface between the plates and creates a ridge. When two oceanic plates are coming together, the older denser plate/crust is subducted or pulled beneath the other plate and creates a trench. Combinations of different plates can result in different outcomes.

Here are links to some websites you might like:

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How are sedimentary rocks different from igneous and metamorphic rocks?

Gazza
Featured 2 months ago

See details below...

Explanation:

The foundation of geology is the study of igneous, sedimentary and metamorphic rocks. The types of rocks are interconnected by a set of processes called the rock circle.

• Igneous rocks form when magma or lava cools and hardens. When the red hot lava cools, a dark-colored igneous rock called basalt will form. If this melted material had stayed deep beneath Earth’s surface, a very different kind of igneous rock would have been produced as the material cooled. Different kinds of igneous rocks form when magma and lava cool and harden.
The word igneous comes from the Latin word ignis, which means “fire.” Perhaps that is why people often associate igneous rock with fiery volcanic eruptions.

There are two types of Igneous rocks:

• Intrusive igneous rock are form when magma hardens beneath Earth’s surface.
• Extrusive igneous rock is when lava hardens.

(https://en.wikipedia.org/wiki/Igneous_rock)
• Sedimentary rocks
All sedimentary rocks begin to form when existing rocks are broken down into sediments. The word sedimentary comes from the Latin word sedimentum, which means “settling.” Sedimentary rocks form when solids settle out of a fluid such as water or air.

https://geology.com/rocks/sedimentary-rocks.shtml)
• Metamorphic rocks
Recall that metamorphic rocks form when existing rocks are changed by heat and pressure. Metamorphism is a very appropriate name for this process because it means to change form. Rocks produced during metamorphism often look much different from the original rocks, or parent rocks.

(https://geology.com/rocks/metamorphic-rocks.shtml)

Thus,

The difference is that:
Sedimentary rocks are usually formed under water when grains of broken rocks are glued together while igneous rocks form when melted rock (magma or lava) cools and metamorphic are rocks that once were igneous or sedimentary rocks but have been changed by pressure and temperature.

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What is about 7/10 of earth's fresh water?

Ms. Worth
Featured 2 months ago

About 70% of the earth's fresh water is frozen in glaciers and in the two polar ice caps.

Explanation:

About 71% of the surface of the earth is covered in water.

Most of that (97%) is $\text{salt}$ water in the oceans and seas.

But there is a little bit of $\text{fresh}$ water too.
Only about 3% of all the water on earth is $\text{fresh}$ water.

$\text{Fresh}$ water is found underground, or in lakes and rivers.

But the vast majority of the earth's $\text{fresh}$ water is in the ice caps of the North and South poles.

These frozen ice sheets contain about 70%# of all the fresh water in the world.

Here's an image showing the relative amounts of water on earth

https://curiosity.com/topics/70-of-earths-fresh-water-is-frozen-curiosity/

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What are the different types of fossils?

Gazza
Featured 2 months ago

See below...

Explanation:

The different types of fossils include:

• Petrified fossils
• Molds fossils
• Casts fossils
• Carbon films
• Preserved remains
• Trace fossils

Each of them form in different ways...

Petrified fossils:
Fossils often form when an organism’s remains become petrified, or “turned into stone.” In this process, mineral-rich water soaks into the small cavities and pores of the original organ- ism. The minerals precipitate from the water and fill the spaces.

Molds fossils:
A fossil mold is created when a shell or other structure is buried in sediment and then dissolved by underground water. The mold reflects only the shape and surface markings of the organism. It doesn’t reveal any information about its internal structure.

Casts fossils:
Cast fossils are created if the hollow spaces of a mold are later filled with mineral matter.

Carbon films:
Fossils called carbon films can preserve delicate details of leaves and animal parts. The formation of a carbon film begins when an organism is buried under fine sediment. Over time, pressure squeezes out liquids and gases and leaves behind a thin film of carbon. Black shale often contains carbon film fossils. Sometimes, the carbon film itself is lost from a fossil. However, an impression of the fossil may remain.