Naked Science Forum

Non Life Sciences => Geology, Palaeontology & Archaeology => Topic started by: gemlove on 15/10/2009 00:52:05

Title: Why can there not be small ripples in coarse sand?
Post by: gemlove on 15/10/2009 00:52:05

Last week on an exam there was a bonus questing asking why small ripple marks cannot be developed in coarse sands. I said that because the sand is coarse, small ripples will not form. I know it is very broad and I figure that is why I got it wrong. But he did not give us the right answer. Why is this I don't get it?

Title: Why can there not be small ripples in coarse sand?
Post by: gemlove on 15/10/2009 01:04:49

<question>, I really should proof read!

Title: Why can there not be small ripples in coarse sand?
Post by: billyjoebob on 15/10/2009 05:05:47

doc already gave us the answer to this one in class :-I

Title: Why can there not be small ripples in coarse sand?
Post by: JimBob on 15/10/2009 15:56:12

Hummm ...

This of course is a logical answer GL, but ...... ??

One of the alternative reason I can think of is the energy required to move the sand grains. Small ripple marks are usually indicative of a low energy environment. It is very unlikely that larger grains move as easily as small grains in a low energy environment.

The larger the grains, the more energy required to move them. 

Quote from: billyjoebob on 15/10/2009 05:05:47

doc already gave us the answer to this one in class :-I

Is that  a smirk??

Title: Why can there not be small ripples in coarse sand?
Post by: gemlove on 15/10/2009 16:33:51

That is pretty much what I guessed. I always second guess myself - and also think processes are more complicated than they really are. And I bet doc explained it that only time I ever missed class! Thanks JimBob!!

Title: Why can there not be small ripples in coarse sand?
Post by: frethack on 15/10/2009 22:16:24

That was my guess as well.  If you have enough energy to only allow large grains to fall from the water column, then it is probably enough energy that small ripples will not be created.  JimBob is always very GeoLOGICAL  [;D]

btw...are you taking sedimentology, gemlove?  Where do you go to hell...err...school?

Title: Why can there not be small ripples in coarse sand?
Post by: JimBob on 17/10/2009 16:43:58

Quote from: frethack on 15/10/2009 22:16:24

That was my guess as well.  If you have enough energy to only allow large grains to fall from the water column, then it is probably enough energy that small ripples will not be created.  JimBob is always very GeoLOGICAL  [;D]

btw...are you taking sedimentology, gemlove?  Where do you go to hell...err...school?

Patronizing little fart - you only want my help with your senior project and a free lunch with Lundelius.
 

Title: Why can there not be small ripples in coarse sand?
Post by: frethack on 18/10/2009 02:07:53

Quote from: JimBob on 17/10/2009 16:43:58

Patronizing little fart - you only want my help with your senior project and a free lunch with Lundelius.
 

Whatever...I want your cornbread too! (This mans cornbread makes you want to slap your granny  [O8)])

We can discuss this at halftime tomorrow, JimBob...hehehe

Title: Why can there not be small ripples in coarse sand?
Post by: JimBob on 18/10/2009 03:06:50

Quote from: frethack on 18/10/2009 02:07:53

Quote from: JimBob on 17/10/2009 16:43:58

Patronizing little fart - you only want my help with your senior project and a free lunch with Lundelius.
 

Whatever...I want your cornbread too! (This man's cornbread makes you want to slap your granny  [O8)])

We can discuss this at halftime tomorrow, JimBob...hehehe

I also get to correct your punctuation. (Cornbread recipe from cookbook.)