Geocentric Science

9 Articles About Plate Tectonics

1

Continental Drift

In the early 1900s, Alfred Wegner introduced the idea of continental drift. This theory had four main components. The continents look like they fit together like a puzzle and then drifted apart. When all of the continents fit together, they formed one original landmass (or a super continent) known as Pangaea. There are similar rock types, fossils, plants, and glacial remnants on the matching shorelines of the continents. There are fossils of tropical plants and animals in polar regions.

2

Earthquakes

Refer to the Tectonic Plates diagram on page 5 of the Earth Science Reference Tables An earthquake is the shaking or trembling of the Earth’s surface. Most earthquakes are the result of sudden movement along a fault (planes of weakness in the crust). Earthquakes can also be caused by volcanic eruptions, as well as human activity (such as explosions). Along plate boundaries and other locations where there is movement of the Earth’s crust, the rock is under immense stress. The rock w

3

Evidence of Ocean Floor Spreading

Research gathered in the 1950s lead Professor Harry Hess to propose the idea of seafloor spreading. However, before Harry Hess, Alfred Wegner first purposed the idea of continental drift. The Theory of Plate Tectonics was built upon these ideas. Mid-Ocean Ridge: Large-underwater mountain chains are found in all ocean basins. These mountain ranges are the result of a divergent plate boundary, where the Earth’s crust is ripped apart as magma rises and forces the lithosphere apart. The older r

4

Plate Boundaries

Refer to the Tectonic Plates diagram on page 5 and the Inferred Properties of Earth’s Interior diagram on page 10 of the Earth Science Reference Tables The Earth’s plates move as a result of convection currents within the mantle. The moving plates create earthquakes where the plates meet and where they are ripped apart. (Refer to the Earthquakes article). There are three types of plate boundaries. These include: Convergent Plate Boundaries Two or more tectonic plates come tog

5

Seismic Waves

Refer to the Tectonic Plates diagram on page 5 and the Inferred Properties of Earth’s Interior diagram on page 10 of the Earth Science Reference Tables Seismic waves are also known as earthquake waves. Once rock reaches its elastic limit, and the rock snaps back and forth releasing the built-up stress, energy is released. The energy (or vibrations) are transmitted through the rock outwards in all directions. What are the different seismic waves? Answer: There are surface waves (transp

6

The Dynamic Earth

Earth’s crust (or lithosphere) is continually moving and changing; mountains and volcanoes are created and then worn away. Today, we see evidence of the dynamic planet in the form of volcanic eruptions, displaced structures, tilted and deformed rocks, sedimentary rocks layers at high elevations, and earthquakes.

7

The Theory of Plate Tectonics

Refer to the Tectonic Plates diagram on page 5 and the Inferred Properties of Earth’s Interior diagram on page 10 of the Earth Science Reference Tables By the 1960s, there was enough evidence to support seafloor spreading (refer to Evidence of Ocean Floor Spreading). However, scientists also knew that the entire crust was not capable moving in all directions at once if it was a solid shell. The Theory of Plate Tectonics was born in order to explain the movement of the lithosphere and scie

8

Tsunamis

Tsunamis (also known as seismic sea waves and are commonly called tidal waves) are large waves often generated by earthquakes (tides do not influence or cause tsunamis). Most tsunamis result from water that is displaced when there is movement along a fault located on the ocean floor. However, tsunamis are also triggered by large underwater landslides, underwater volcanic eruptions, and meteor impacts with the ocean. Image from Wikipedia Once a tsunami is generated, energy is moved at high spe

9

Volcanic Eruptions: Environmental Impact and Hazards

Refer to the Tectonic Plates diagram on page 5 and the Selected Properties of Earth’s Atmosphere diagram on page 14 of the Earth Science Reference Tables Volcanic eruptions are extremely common along plate boundaries. However, since New York is not located along a plate boundary, we tend to only hear about the large and destructive eruptions. In April 2010, Iceland’s Eyjafjallajokull volcano erupted explosively and spewed out huge amounts of lava, rock, ash, and harmful gases into t