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Author Topic: what's the difference between weathering and erosion?  (Read 8207 times)

paul.fr

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Offline Bass

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what's the difference between weathering and erosion?
« Reply #1 on: 14/09/2007 23:44:26 »
I generally think of erosion as the displacement of particles- commonly, but not exclusively, by water.  Pieces are broken or worn off and physically moved to another location.
Weathering doesn't require particles to be moved or displaced.  Weathering will alter rock or soil, but without having to move atual particles.  Chemical weathering is very important in mineral exploration- it spreads indicator elements and can either enrich or diminsh ore deposits.
Typically, erosion and weathering go hand in hand.
 

Offline JimBob

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what's the difference between weathering and erosion?
« Reply #2 on: 15/09/2007 03:26:55 »
Large pieces of rock can be eroded over time by the release of pressure and also freezing and thawing as well. Rocks sometimes just fall or slide off the slide of mountains - we all have seen examples of this on the news. Another release of pressure type of "weathering" is the spalling off of large pieces of granite. The granite is formed underground and thus under pressure. When the surface of the earth is eroded down to expose the granite the pressure is relieved in all directions outward. This is why many outcrops of granite have rounded features.

This weathering and the other one mentioned is sometimes helped along by water freezing in small crack,expanding as it freezes and putting just a little pressure on the crack. Over time the effects of the repeated freezing and thawing causes the pieces to fall off. But freezing does not need to occur for the two types of weathering to occur. It has happened in Hawaii to basalt, it happens in equatorial Africa to granite.

 
 

Offline Ophiolite

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what's the difference between weathering and erosion?
« Reply #3 on: 17/09/2007 17:04:33 »
A way of summarising both the above posts would be to say that weathering involves the physical and chemical alteration of rocks at surface or near surface conditions, and erosion involves the removal of rock material, again by either physical or chemical means.
 

Offline DrDick

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what's the difference between weathering and erosion?
« Reply #4 on: 17/09/2007 17:38:36 »
So far, it seems to me so far like the difference between 6 and a half dozen.

According to Dictionary.com, weather means (definition #6)
Quote
to discolor, disintegrate, or affect injuriously, as by the effects of weather: These crumbling stones have been weathered by the centuries.

So, weathering is a general term, including simple discoloration and the more injurious erosion.

Dick
 

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what's the difference between weathering and erosion?
« Reply #4 on: 17/09/2007 17:38:36 »

 

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