GEOLOGY
STRATIGRAPHY
|
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
|
|
|
Earth’s climate is constantly changing.
|
|
|
Dinosaurs went extinct about 6.5 million years ago.
|
|
|
The continents have been consistently moving over time.
|
|
|
Oceans are much deeper today than they were millions of years ago.
|
Detailed explanation-1: -Earthquakes shout into the earth’s interior and their echoes reveal a hidden world of moving plates, regions of swirling rock and subterranean oceans of molten iron. The study of earthquake waves in the last one hundred years has provided an explosion of information about the earth’s interior.
Detailed explanation-2: -Knowing how the waves behave as they move through different materials enables us to learn about the layers that make up the Earth. Seismic waves tell us that the Earth’s interior consists of a series of concentric shells, with a thin outer crust, a mantle, a liquid outer core, and a solid inner core.
Detailed explanation-3: -Earthquakes occur along fault lines, cracks in Earth’s crust where tectonic plates meet. They occur where plates are subducting, spreading, slipping, or colliding. As the plates grind together, they get stuck and pressure builds up. Finally, the pressure between the plates is so great that they break loose.
Detailed explanation-4: -The heat from radioactive processes within the planet’s interior causes the plates to move, sometimes toward and sometimes away from each other. This movement is called plate motion, or tectonic shift.
Detailed explanation-5: -By looking at the amount of time between the P and S wave on a seismogram recorded on a seismograph, scientists can tell how far away the earthquake was from that location. However, they can’t tell in what direction from the seismograph the earthquake was, only how far away it was.