Tectonic Activity and Hazards
Tectonic hazards are natural events caused by the Earth's plate movement, it can cause a potential threat to humans and infrastructure. The damage created by tectonic hazards varies in different areas of the world, so it it important to do further research. It would be interesting to compare previous hazards with recent ones and find a link.
Tectonic hazards can trigger other more impact full hazards. Tectonics activity also cause some interesting landscapes, such as faults and rift valleys. They can be a great risk to human populations the risk implied on the areas can be calculated by looking at the disaster risk equation. This will involve looking at the hazard itself; look at the magnitude and frequency of the event, then research more about vulnerability of the areas this will involve looking at economic development, geographical location and social factors such as education and preparedness. Hazard impact can vary and can be done on a different scale, within this, it can short term or long term and we can look at how it affects the economy, the environment and people.
Furthermore, we will look at how people respond to hazards and their risks.
Tectonic hazards are natural events caused by the Earth's plate movement, it can cause a potential threat to humans and infrastructure. The damage created by tectonic hazards varies in different areas of the world, so it it important to do further research. It would be interesting to compare previous hazards with recent ones and find a link.
Tectonic hazards can trigger other more impact full hazards. Tectonics activity also cause some interesting landscapes, such as faults and rift valleys. They can be a great risk to human populations the risk implied on the areas can be calculated by looking at the disaster risk equation. This will involve looking at the hazard itself; look at the magnitude and frequency of the event, then research more about vulnerability of the areas this will involve looking at economic development, geographical location and social factors such as education and preparedness. Hazard impact can vary and can be done on a different scale, within this, it can short term or long term and we can look at how it affects the economy, the environment and people.
Furthermore, we will look at how people respond to hazards and their risks.
![Picture](/uploads/2/0/5/8/20583994/1923757.gif?364)
The Earth and why do tectonic plates move?
The Earth is made up of different components that are made up of different liquid metal that have varying temperature. We live on the top part of the Earth, which is the crust, movements from the mantle can affect us. when a plate is formed it will have an average density (crust is low density, buoyant and welded to high density mantle lithosphere) which is lower than the asthenospheric mantle below it. In time, as the crust cools and the high density portion thickens to the point where the average density exceeds that of the lower mantle. Once this happens the plate will sink due to gravity, causing subduction. Which side of the plate this happens on determines the direction of movement (although the spreading at ocean ridges is in both direction. The rate depends largely on how much subduction is taking place on a given plate and a combination of frictional forces resisting it plus how fast the mid ocean ridges are spreading (determined by how hot the asthenospheric mantle beneath the spreading centre is, hotter is faster). Mantle convection does play a role in building heat beneath the crust to initiate seafloor spreading. However the material is not dense enough to solely drive plate tectonics, it can assist in the rate of movement but can also impede it.
The Earth is made up of different components that are made up of different liquid metal that have varying temperature. We live on the top part of the Earth, which is the crust, movements from the mantle can affect us. when a plate is formed it will have an average density (crust is low density, buoyant and welded to high density mantle lithosphere) which is lower than the asthenospheric mantle below it. In time, as the crust cools and the high density portion thickens to the point where the average density exceeds that of the lower mantle. Once this happens the plate will sink due to gravity, causing subduction. Which side of the plate this happens on determines the direction of movement (although the spreading at ocean ridges is in both direction. The rate depends largely on how much subduction is taking place on a given plate and a combination of frictional forces resisting it plus how fast the mid ocean ridges are spreading (determined by how hot the asthenospheric mantle beneath the spreading centre is, hotter is faster). Mantle convection does play a role in building heat beneath the crust to initiate seafloor spreading. However the material is not dense enough to solely drive plate tectonics, it can assist in the rate of movement but can also impede it.
Where are the tectonically active regions of the world?
The major plates are the Antarctic plate, African plate, Eurasian plate, Australian plate, Pacific plate, North American plate, South American plate and Nazca plate. There are also a number of minor plates, such as the Arabian plate, Caribbean plate, Indian plate and Philippine plate. These plate boundaries are associated with geological events such as earthquakes and the creation of mountains, volcanoes and oceanic trenches. Most of the world’s active volcanoes occur along plate boundaries – the most active plate is the Pacific plate's Ring of Fire.
The major plates are the Antarctic plate, African plate, Eurasian plate, Australian plate, Pacific plate, North American plate, South American plate and Nazca plate. There are also a number of minor plates, such as the Arabian plate, Caribbean plate, Indian plate and Philippine plate. These plate boundaries are associated with geological events such as earthquakes and the creation of mountains, volcanoes and oceanic trenches. Most of the world’s active volcanoes occur along plate boundaries – the most active plate is the Pacific plate's Ring of Fire.
![Picture](/uploads/2/0/5/8/20583994/719754.png)
Transform plate boundaries
Transform plate boundaries (or conservative plate boundaries) exist due to two plate boundaries sliding horizontally past each other, they are most commonly found on ocean floor and about 5 are on land. No land is created or destroyed in this event – but a linear fracture called a fault is formed. When plates slide past each other, they release great amount of pressure which often triggers earthquakes.
Most transform plate boundaries are related to divergent and convergent plate boundaries that sometimes go across a continent.
Transform plate boundaries (or conservative plate boundaries) exist due to two plate boundaries sliding horizontally past each other, they are most commonly found on ocean floor and about 5 are on land. No land is created or destroyed in this event – but a linear fracture called a fault is formed. When plates slide past each other, they release great amount of pressure which often triggers earthquakes.
Most transform plate boundaries are related to divergent and convergent plate boundaries that sometimes go across a continent.
![Picture](/uploads/2/0/5/8/20583994/2623230.png?491)
There are 3 main types of transform plate boundaries: Ridge-ridge transform faults, ridge-trench transform faults and trench-trench transform faults.
1- Ridge-ridge transform faults are by the most common ones.
2- Ridge-trench transform faults
3- Trench-trench transform faults are not very common, but an example of it is the Alpine Fault in New Zealand. It seems that it links two trenches in the South Pacific.
1- Ridge-ridge transform faults are by the most common ones.
2- Ridge-trench transform faults
3- Trench-trench transform faults are not very common, but an example of it is the Alpine Fault in New Zealand. It seems that it links two trenches in the South Pacific.
![Picture](/uploads/2/0/5/8/20583994/227019.png?312)
Divergent plate boundaries
This is when two plates move away from each other; new land is created in this process. When the plates diverge, land between the faults breaks and a drop into the interior, (which is the asthenosphere) a rift is then formed. Magma flows upward and fills in the gap and cools, so new land is formed. Rift valleys are formed and volcanoes often form at areas where the magma reaches the surface. Earthquakes are often triggered along the fault.
This is when two plates move away from each other; new land is created in this process. When the plates diverge, land between the faults breaks and a drop into the interior, (which is the asthenosphere) a rift is then formed. Magma flows upward and fills in the gap and cools, so new land is formed. Rift valleys are formed and volcanoes often form at areas where the magma reaches the surface. Earthquakes are often triggered along the fault.
![Picture](/uploads/2/0/5/8/20583994/4863208.png)
Convergent plate boundaries
When two plates are moving towards each other they are said to be convergent plate boundaries, here some of the crust is destroyed. During the converging process, plates are said to be subducted and an area where a plate is subducted is called a subduction zone. There are three types of convergent plate boundaries, and they can either created mountain or volcanoes. The three type are; Oceanic-Continental Convergence; Oceanic-Oceanic Convergence; and Continental-Continental Convergence.
When two plates are moving towards each other they are said to be convergent plate boundaries, here some of the crust is destroyed. During the converging process, plates are said to be subducted and an area where a plate is subducted is called a subduction zone. There are three types of convergent plate boundaries, and they can either created mountain or volcanoes. The three type are; Oceanic-Continental Convergence; Oceanic-Oceanic Convergence; and Continental-Continental Convergence.
![Picture](/uploads/2/0/5/8/20583994/7595363.png)
Oceanic-Continental Convergence:
When a continental plate and oceanic plate are moving towards each other, the oceanic plate is subducted under the continental plate due to it being denser. During this process, the oceanic crust can melt and magma can go up and create a volcano, or even create folded mountain like the Andes during movements of the plates, earthquakes are always present.
When a continental plate and oceanic plate are moving towards each other, the oceanic plate is subducted under the continental plate due to it being denser. During this process, the oceanic crust can melt and magma can go up and create a volcano, or even create folded mountain like the Andes during movements of the plates, earthquakes are always present.
![Picture](/uploads/2/0/5/8/20583994/8503373.png)
Oceanic-Oceanic Convergence:
When two oceanic plates converge, one is subducted under the other plate, this then forms oceanic trenches, and for example the Mariana Trench and it can also create undersea volcanoes.
When two oceanic plates converge, one is subducted under the other plate, this then forms oceanic trenches, and for example the Mariana Trench and it can also create undersea volcanoes.
![Picture](/uploads/2/0/5/8/20583994/743442.png)
Continental-Continental Convergence:
When two continental plate are converging toward each other, neither plates are subducted sue to the plate being light so they go upward creating mountain, the Himalayas was created after the convergence of the Indian and Eurasian plate.
When two continental plate are converging toward each other, neither plates are subducted sue to the plate being light so they go upward creating mountain, the Himalayas was created after the convergence of the Indian and Eurasian plate.