Geologists have known for about 100 years that the Earth is composed of four layers; the Crust, the Mantle, the Outer Core, and the Inner Core .
Scientists still argue about the makeup of these layers and exactly how each layer interact with the other layers. We are not even sure how the layers were formed but we have some theories.
Because we can not go to the center of the earth we have to find our answers otherwise.
<span>This is what a geologist by the name of Andrija Mohorovicic did. He discovered in 1909 that earthquake waves near the surface moved slower than earthquake waves that passed through the interior of the Earth. He also noticed that the P (primary, first and strongest) waves that passed through the interior of the Earth did not do so in a straight line. These waves were bent or deflected by something! </span>
What the scientist knew was that waves of all kinds move faster and straighter through denser, more solid objects.
<span>So Mohorovicic came to the conclusion that the outside layer or Crust was made of less dense material (Rock) and the next layer, the Mantle was much denser. This would explain why the earthquake waves moved slower through the crust. </span>
<span>So by looking at the seismic waves from earthquakes the scientist learned about the crust and the mantle but they also learned about the outer and inner core. </span>
To do this you have to look at a different kind of waves, the S (secondary waves) waves that also get released by an earthquake. These S waves are slower.
<span>Beno Gutenberg , a German geologist, believed that the Outer Core must be made of a liquid because the slower S waves could not pass through this layer and in fact "bounced off" and were deflected many degrees off course. </span>
<span>The fourth layer, the Inner Core, is composed of very, very hot metals (iron and nickel) with pressures so great that the metals do not flow as a liquid, but are forced to vibrate in place like a solid. </span>
<span>Earthquake waves that reach this layer move at the greatest speeds because waves move through solids faster than through gases and liquids. </span>
This is how we know that there have to be different layers. Otherwise the behavior of the different seismic waves would not make sense.
Answer:
energy, carbon dioxide, and water
The reason large bodies of water do not quickly fluctuate in temperature is because water has a high heat capacity.
Answer:
This question is incomplete as it does not contain the graphical representation of fishes population over time. The image containing this information has been attached in the attachment section.
The correct answer is D. The nitrogen from the fertilizer made the plants grow too quickly, which hurt the fish.
Explanation:
According to the attached image, artificial fertilizer is being used on a an apple orchard for six years. The orchard is located near a stream which runs out into a small bay.
Based on the results of the sampled population of fishes for five years as represented graphically by researchers (see attached image), it is obvious that the population of the fishes in the bay is reducing over the years. They also observed the growth of plantlike organisms in the bay.
The possible cause of this decline in the population of fishes is the increased growth of these plantlike organisms. The plantlike organisms are algae, which uses the nitrogen content of the artificial fertilizer that washes into the bay from the orchard, as a source of nutrient. This excessive nutrient causes the plantlike organisms to bloom or grow too rapidly- a process called EUTROPHICATION.
Eutrophication causes the oxygen content of the bay to reduce gradually as the blooming of the plantlike organisms depletes oxygen in the water body, thereby, harming aerobic aquatic organisms like fishes in the bay.
Hence, in a nutshell, the reduction in the population of fishes in the bay is as a result of the nitrogen from the fertilizer which made the plantlike organisms grow too quickly, leading to oxygen-depletion and subsequently death of the bay fishes.
Answer:
Spits
Explanation:
Spits are also caused by deposition - they are features that are formed by the process of longshore drift. A spit is an extended stretch of beach material that only joins the mainland at one end. They start to form where there is a change in the direction of the coastline.
