Summarize Advances Over Time Essay
Rosemary Hurrey
EAS-101-OL009
10 July 2013
Written Assignment 1
Answer the following questions.
1.Summarize advances over time in determining the age of the Earth, including the importance of the discovery or radioactivity. Throughout the past few decades, there have been advancements in new techniques to help determine the age of the Earth. Currently scientific evidence believes that the Earth is between 4.5 and 4.6 billions years old. To help determine the age of the earth, radiometric dating has allowed scientists to determine ages and length of specific periods, eras and epochs. Using rocks that are on the Earth’s surface or found through drilling are helping scientists advance in determining the age of Earth and how these changes …show more content…
The primary energy source in seismic tomography is seismic waves. Seismic waves are generated by earthquakes, which are recorded on seismograms around the world. Another way that seismic tomography has been used is through crosshole transmission tomography. This is used to image subsurface features between boreholes and is very accurate. Seismic tomography has also been used to characterize fractured bedrock, map groundwater reservoirs and other bodies of water, it also helps locate hotspots and help scientist determine convection patterns in the mantle. Because seismic tomography uses seismic waves, which are cause by earthquakes, plate tectonics are also a factor. Plate tectonic movements are what cause earthquakes throughout the world. When these plates start to move apart, the ocean floor is extended, which is called sea-floor spreading. When these earthquakes occur, magma rises and starts to go on the ocean floor, just as a volcano wood, except it is underground. As more of this magma starts to build up on the ocean floor, it creates chains of mounts called an oceanic ridge. This allows the ocean floor to continue to spread and the sizes of the plates get
EAS-101-OL009
10 July 2013
Written Assignment 1
Answer the following questions.
1.Summarize advances over time in determining the age of the Earth, including the importance of the discovery or radioactivity. Throughout the past few decades, there have been advancements in new techniques to help determine the age of the Earth. Currently scientific evidence believes that the Earth is between 4.5 and 4.6 billions years old. To help determine the age of the earth, radiometric dating has allowed scientists to determine ages and length of specific periods, eras and epochs. Using rocks that are on the Earth’s surface or found through drilling are helping scientists advance in determining the age of Earth and how these changes …show more content…
The primary energy source in seismic tomography is seismic waves. Seismic waves are generated by earthquakes, which are recorded on seismograms around the world. Another way that seismic tomography has been used is through crosshole transmission tomography. This is used to image subsurface features between boreholes and is very accurate. Seismic tomography has also been used to characterize fractured bedrock, map groundwater reservoirs and other bodies of water, it also helps locate hotspots and help scientist determine convection patterns in the mantle. Because seismic tomography uses seismic waves, which are cause by earthquakes, plate tectonics are also a factor. Plate tectonic movements are what cause earthquakes throughout the world. When these plates start to move apart, the ocean floor is extended, which is called sea-floor spreading. When these earthquakes occur, magma rises and starts to go on the ocean floor, just as a volcano wood, except it is underground. As more of this magma starts to build up on the ocean floor, it creates chains of mounts called an oceanic ridge. This allows the ocean floor to continue to spread and the sizes of the plates get