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Geophysics
The study of Earth using the combination of Geology and Physics, it lets us understand what is going on under the Earth's surface. Find questions on different types of seismic activities such as earthquakes and volcano eruptions here.
1,480 Questions
What are the benefits of using wood?
Wood is a renewable resource. It is strong, light, fairly easy to work and work with, and it lasts pretty well. It is relatively inexpensive, broadly available, and can be adapted to make lots of wonderful things from kitchen spoons to houses. And when we look at the custom turnings or crafted wood furnishings produced over the years, we see some of the most wonderful grain and coloration in this ancient building material.
What conditions makes it difficult to predict the occurrence of earthquakes?
Earthquakes and volcanic eruptions are extremely hard to predict because of their irregularity. This is due to the butter fly effect. For example, in California there had been a volcanic eruption every 30 years since the start of their records, so they a few years ago when it was scheduled to happen the government spent millions on "earthquake-proofing" the area. Nothing actually happened. The main way to predict earthquakes and volcanic eruptions is to look for patterns in the past but it is really not an accurate or reliable method. Earthquakes are a lot harder to predict as they can happen at any point down a convergent or conservative plate boundary spontaneously, where as with a volcano you can study it and look for signs such as bulges or changes of gas composition in the area that could indicate when it will erupt. However new methods of detection are being tested, the strangest being the use of some animals, snakes the most common, that behave in peculiar ways just before an earthquake. Breakthroughs like these and the use of new technologies, like GPS to monitor irregularities in the the shape of volcanoes, will make the prediction of earthquakes and volcanic eruptions much easier in the future
What role does magma play in the rock cycle?
Volcanoes effect rock formations a lot, since magma is molten rock, when it cools down and sets, it will turn back into rock, usually it will dry and turn black, but sometimes it can turn a dark grey. It will cover up other rocks, and make new rocks.
How does the slope of an area affect its runoff?
It really depends on the slope. If it is a steep slope, the runoff will flow downhill faster and collect more at the bottom. If it is a pretty level slope, the runoff won't collect at the bottom of it. The water will just flood the top of the slope.
Where does photsynthesis take place?
Photosynthesis takes place in the chloroplasts of plant cells. Chloroplasts contain chlorophyll, a green pigment that captures sunlight and converts it into energy through a series of chemical reactions.
What are the two types of deposition?
your question is not clear as it is,and i tend to think you meant depositional environments.in case of deposition environments we have;continental(fluvial,aeolian,alluvial),transitional environment (lagoons,beach),marine environment (reef,shallow and deep marine) and glacial environment.
Why is air resistance a frictional force?
If you drop an elephant and an equal weight amount of feathers, the elephant will hit the ground first. The elephant falls faster than the feather because it never reaches a terminal velocity; it continues to accelerate as it falls accumulating more and more air resistance.
What is the warping of the earth crust?
deformation of flat structures which had undergone tectonic movements.
Intensity
What are the main ingredients of magma?
Magma is composed of molten silicate minerals, dissolved gasses, and sometimes crystallized minerals.
Where are places that mass wasting can occur?
Three kinds of mass movements are slumping, rockfalls, and mudflow/landslides. Slumping is found in coastal areas where there is a hard permeable layer of rock on top (e.g. sandstone) of a soft impermeable layer of rock (e.g. clay). It involves a rotational slip on a concave sliding surface. Erosion occurs by saturating the top layer of rock, making it heavy, and forcing it down the slip. As the soft rock is impermeable, rain cannot seep through therefore it is not saturated.
What are things that people can do to control the processes that change earth's surface?
You can stop by not polluting thewater in ponds, lakes, beaches, or oceans.
What does the theory of continental drift explain?
The idea that the continents were once one super-continent and subsequently moved apart is the basis of the theory of continental drift. Continental drift was first proposed as a scientific hypothesis with evidences by Alfred Wegener early in the twentieth century. Unfortunately, the evidence he was able to cite, such as similarities in coastline geographies and fossils on either side of the Atlantic, did not provide an explanation for the mechanism which caused it to happen. In Wegener's theory, the continents were somehow able to plow through the oceans. It wasn't until the mid-twentieth century that the Atlantic Ridge system was discovered. Further investigation revealed that the magnetic orientation of rock on either side of the ridge matched the orientation on the other side of the ridge, providing the proof for the mechanism that caused the continents to move apart. Basaltic magma was infilling the area on either side of the ridge to create new continental crust. Subduction of older, denser oceanic crust takes place at collision zones where it meets less dense oceanic and continental crust. The whole process is driven by gravity and heat from the Earth's interior via convection currents in the mantle. The process is no longer called continental drift, but is referred to as plate tectonics.
Alfred Wagner's theory was that the sea floor was spreading, causing the continents to 'drift'. The theory was originally tossed aside because the fact that the continents fitted together was not sufficient.
How often is there a polar reversal?
Why can't the wind lift and carry large particles?
It has to the with the ratio of cross-sectional area to volume. If an object expands in size while keeping the same proportions the ratio of its cross sectional area to its volume decreases. If we assume a constant density, then the ratio of cross sectional area to mass increases as well. For example, if we take a sphere and double its diameter, its volume will increase eight times while its cross-sectional area will only increase four times. The force an object experiences from wind is proportional to its cross-sectional area while the maximum force holding it in place is usually proportional to its mass.
How plates move to cause earthquakes?
It result from the moving of rock deep under the ground. This movement is caused by the rubbing of one plate into another. The plates have jagged edges, and so when they rub against each other, they get stuck. Since plates constantly move, the plates that are stuck create great tension, and when they are finally free, a huge amount of energy is released. Shock waves move from focus in all directions, and it causes the earth to vibrate.
Tectonic plates causes earthquakes when two or more plates collide with each other.
Pressure builds up between plates and causes an earth quake.
The Earth's surface is formed form a number of interlocking plates which are moved round by the convection of the underlying mantle (as it cools). This means that in some places the plates are being torn apart, in other places the plates are sliding past one another and in yet other places the plates are being squeezed together. These underlying plate movements provide the energy given off as earthquakes. The heat given off by the mantle is the source of energy for volcanoes which also occur near the plate margins.
Earthquakes happen when the rocks breaks under pressure, rather like snapping a stick. As the plates move the rocks deform elastically (like a stick bending) and when eventually the rocks break under the stress, its snaps back to its original shape. This snap back is called elastic rebound. When the rock breaks and rebounds, its gives off energy. This energy causes the ground to shake.
Friction also increases the amount of energy that is released from that earthquake, which is then affected by the speed of the movement of the tectonic plate.
It result from the moving of rock deep under the ground. This movement is caused by the rubbing of one plate into another. The plates have jagged edges, and so when they rub against each other, they get stuck. Since plates constantly move, the plates that are stuck create great tension, and when they are finally free, a huge amount of energy is released. Shock waves move from focus in all directions, and it causes the earth to vibrate.
Earthquakes are tremors or vibrations in the Earth's crust that are caused by the build up or accumulation of pressure (more correctly termed stress).
This accumulation of stress is due to the movement of tectonic plates and most commonly occurs at the boundaries between differing plates that are moving in different directions. This accumulation of stress causes the rocks that make up the crust to deform elastically. This is very similar to what happens when you squash or stretch a spring and causes a form of energy to be stored in the rocks of the crust - technically described as elastic potential energy.
When this stress gets to large, it exceeds the strength of the rocks in the crust and causes a brittle failure. Brittle failures are failures where fractures form through the material.
This sudden brittle failure causes all of the elastic potential energy to be released at one time in the form of seismic waves, just as if a spring or elastic band that was being stretched suddenly snapped.
These seismic waves cause the tremors that people feel on the surface and which can cause damage to buildings and other structures.
Stars are primarily made up of hydrogen and helium gas, which undergo nuclear fusion in their core to generate heat and light. This fusion process is what sustains a star's energy output and prevents it from collapsing under its own gravity. So in a way, stars can be thought of as massive balls of gas undergoing nuclear reactions.
Which volcano last erupted in 1809?
Mount Tambora in Indonesia last erupted in 1815, not 1809. This eruption was one of the most powerful in recorded history and had significant global impacts, leading to the "Year Without a Summer" in 1816.
Pieces of evidence that support the fact the earth's crust is moving?
The fossils, animals, plants, and same type of stuff that is found both on one continent, and on a completely different continent. For example, a 'fern' is found on South America that is the same 'fern' on an edge of Europe. This suggests that these two continents were once connected. *fern is made up.
What is a seismic safe building?
No building is seismic safe. No building is earthquake proof. However, there are steps that can be taken to make buildings more earthquake resistant. Concrete buildings made without rebar will collapse in an earthquake. Concrete buildings and concrete block buildings in Guatemala that hold up in earthquakes are those that use a lot of rebar. It is also important to use metal straps to tie the roof to the walls. The straps are inexpensive, but they maintain the integrity of the building. The roof should have cross pieces.
What is elastic limit in relation to earthquakes?
How far you can bend (or stretch) something before it fails to return to its original shape when released.
What forms where a continental and oceanic plate collide?
Continental Rift - but that assumes they are separating. All of tectonic theory fails to account for erosion and deposition. It is truly half baked theory because the alternative is hydroplate theory and The Flood. Can't entertain notions like that even if the planet makes more sense under that. But its continental rift.
