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Author Topic:   How to make sand.
jar
Member (Idle past 394 days)
Posts: 34026
From: Texas!!
Joined: 04-20-2004


Message 106 of 121 (595972)
12-11-2010 5:07 PM
Reply to: Message 105 by Buzsaw
12-11-2010 4:45 PM


Re: Questions Pertaining To Current Model
Did you read what I wrote?
The current model for making sand is pretty simple. Start with a mountain, a big sucker of a rock. Then the daily transition between warm day time and colder night time, and between hotter summer and colder winter will cause expansion and contraction of the rock, gradually over long periods of time opening small cracks.
Again over time, water will fill the cracks and when it freezes enlarge the cracks, eventually breaking off pieces.
Again, over time the pieces are transported from higher elevations to lower ones by wind, water and gravity. During transportation they are broken up further, becoming smaller and smaller pieces.
Nothing is needed other than processes we can see at work today and lots of time.[/quote]
Buz writes:
1. As per the current model, from whence came mountain size rocks?
From vulcanism and continental drift.
But again, the issue is NOT the current model, it is what the hell is YOUR model?
Buz writes:
2. As per the current model, at what point in time did the first boulder size rock exist?
Irrelevant and just another example of you trying to avoid answering the question.
What the hell is YOUR model?
Buz writes:
3. As per the current model, at what point in time did the first grain of sand exist?
No idea and it is as expected, totally irrelevant and just another example of you trying to avoid answering the question.
What the hell is YOUR model?
Buz writes:
4. Does the current model assume a time when all rocks were mountain size?
Too funny. Of course not. It takes time to build a mountain.
As expected, totally irrelevant and just another example of you trying to avoid answering the question.
What the hell is YOUR model?

Anyone so limited that they can only spell a word one way is severely handicapped!

This message is a reply to:
 Message 105 by Buzsaw, posted 12-11-2010 4:45 PM Buzsaw has not replied

  
Coragyps
Member (Idle past 734 days)
Posts: 5553
From: Snyder, Texas, USA
Joined: 11-12-2002


Message 107 of 121 (595979)
12-11-2010 8:20 PM
Reply to: Message 103 by Buzsaw
12-11-2010 3:37 PM


Re: Questions Pertaining To Current Model
If not, at what point in time would there have been no sand, no gravel, no stones....?
At that point in time, bach in the Hadean, when the crust of the Earth was just solidifying from a molten state and there was just a crust in the "upper layer of a pie" sort of sense. That's when.
Edited by Adminnemooseus, : Fix quote box. Ending with [/i] doesn't do it.

This message is a reply to:
 Message 103 by Buzsaw, posted 12-11-2010 3:37 PM Buzsaw has not replied

  
Dr Adequate
Member (Idle past 284 days)
Posts: 16113
Joined: 07-20-2006


Message 108 of 121 (595983)
12-11-2010 8:44 PM
Reply to: Message 104 by jar
12-11-2010 4:10 PM


Re: Questions Pertaining To Current Model
Well, you failed to clarify the intent of your statement.
the current model is outlined in the Original Post, but I'll repeat it for you.
Well, I don't think you've got that right.
Sand is mostly quartz. The reason for this is that chemical weathering (not, as you seem to suggest, mechanical weathering) dissolves the other minerals in granitic rocks or (in the case of feldspars) converts them to clay.
Quartz is extremely resistant to chemical weathering, so the grains of quartz remain and are transported by wind or water.
This, by the way, explains why there is a maximum size to sand grains --- they have an upper limit set by the way that granite crystalizes as the granite-forming magma cools.
Mechanical weathering, and freezing in particular, plays a relatively small part. (You can tell how large a part mechanical weathering and erosion has played by looking at the composition of the sand: more mechanical weathering and erosion corresponds to a higher proportion of non-quartz material such as feldspar.)

This message is a reply to:
 Message 104 by jar, posted 12-11-2010 4:10 PM jar has replied

Replies to this message:
 Message 109 by jar, posted 12-11-2010 8:47 PM Dr Adequate has replied
 Message 116 by Minnemooseus, posted 12-20-2010 10:09 PM Dr Adequate has replied

  
jar
Member (Idle past 394 days)
Posts: 34026
From: Texas!!
Joined: 04-20-2004


Message 109 of 121 (595984)
12-11-2010 8:47 PM
Reply to: Message 108 by Dr Adequate
12-11-2010 8:44 PM


Re: Questions Pertaining To Current Model
I have no problem including chemical and mechanical weathering.
The point is that sand is created by first raising land up and then wearing it down.

Anyone so limited that they can only spell a word one way is severely handicapped!

This message is a reply to:
 Message 108 by Dr Adequate, posted 12-11-2010 8:44 PM Dr Adequate has replied

Replies to this message:
 Message 110 by Dr Adequate, posted 12-11-2010 9:13 PM jar has seen this message but not replied

  
Dr Adequate
Member (Idle past 284 days)
Posts: 16113
Joined: 07-20-2006


Message 110 of 121 (595988)
12-11-2010 9:13 PM
Reply to: Message 109 by jar
12-11-2010 8:47 PM


Re: Questions Pertaining To Current Model
Well, we might as well be accurate. Apart from anything else, the actual details of the model have greater predictive and explanatory power --- we can explain the normal size and mineral composition of sand grains; whereas someone who maintains that sand was magicked into existence In The Beginning by God has to explain why he made sand consistent with an actualist model rather than, for example, making it out of 3mm grains of feldspar, which he could have done if he wanted to.

This message is a reply to:
 Message 109 by jar, posted 12-11-2010 8:47 PM jar has seen this message but not replied

  
Buzsaw
Inactive Member


Message 111 of 121 (596916)
12-17-2010 10:00 PM


Buzsaw's Absence
Just a note to say that I've not run off from responding. I plan to respond to a couple of posts sometime soon. I've been extremely preoccupied with essential other activities related to business, winterizing and repair of buildings, etc. My first priority when I return will be to finish my preparation for a great debate with Meldinoor as promised.

  
Buzsaw
Inactive Member


Message 112 of 121 (597323)
12-20-2010 8:30 PM
Reply to: Message 104 by jar
12-11-2010 4:10 PM


Re: Questions Pertaining To Current Model
{There may be a bit of on-topic in there, but I'm not going to try to sort it out - Adminnemooseus}
Edited by Adminnemooseus, : Hide and off-topic banner and note.

This message is a reply to:
 Message 104 by jar, posted 12-11-2010 4:10 PM jar has replied

Replies to this message:
 Message 113 by jar, posted 12-20-2010 8:39 PM Buzsaw has not replied
 Message 114 by lyx2no, posted 12-20-2010 10:06 PM Buzsaw has not replied

  
jar
Member (Idle past 394 days)
Posts: 34026
From: Texas!!
Joined: 04-20-2004


Message 113 of 121 (597329)
12-20-2010 8:39 PM
Reply to: Message 112 by Buzsaw
12-20-2010 8:30 PM


Re: Questions Pertaining To Current Model
None of that is a model Buz. First learn what a model is, then come back.
AbE: to try to help Buz get a clue of what is needed.
Buz writes:
The Biblical literal model would be that the planet was, at the time God's spirit began to do the work on it, had a cold watery surface in which the water was mixed in the soil and the rock.
How did the spirit do anything? What evidence is there that there was any soil? what was don and how was it done?
{I'm calling it off-topic. Be careful what you respond to. - Adminnemooseus}
Edited by jar, : try to help Buz get started.
Edited by Adminnemooseus, : Off-topic banner and note.

Anyone so limited that they can only spell a word one way is severely handicapped!

This message is a reply to:
 Message 112 by Buzsaw, posted 12-20-2010 8:30 PM Buzsaw has not replied

  
lyx2no
Member (Idle past 4716 days)
Posts: 1277
From: A vast, undifferentiated plane.
Joined: 02-28-2008


Message 114 of 121 (597336)
12-20-2010 10:06 PM
Reply to: Message 112 by Buzsaw
12-20-2010 8:30 PM


Re: Questions Pertaining To Current Model
Edited by Adminnemooseus, : Hide and off-topic banner.

This message is a reply to:
 Message 112 by Buzsaw, posted 12-20-2010 8:30 PM Buzsaw has not replied

Replies to this message:
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jar
Member (Idle past 394 days)
Posts: 34026
From: Texas!!
Joined: 04-20-2004


Message 115 of 121 (597337)
12-20-2010 10:07 PM
Reply to: Message 114 by lyx2no
12-20-2010 10:06 PM


Sun, moon, days, sand?
Edited by Adminnemooseus, : Hide and off-topic banner.

This message is a reply to:
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Minnemooseus
Member
Posts: 3941
From: Duluth, Minnesota, U.S. (West end of Lake Superior)
Joined: 11-11-2001
Member Rating: 10.0


Message 116 of 121 (597338)
12-20-2010 10:09 PM
Reply to: Message 108 by Dr Adequate
12-11-2010 8:44 PM


Mechanical (physical) vs. chemical weathering
Mechanical weathering, and freezing in particular, plays a relatively small part. (You can tell how large a part mechanical weathering and erosion has played by looking at the composition of the sand: more mechanical weathering and erosion corresponds to a higher proportion of non-quartz material such as feldspar.)
Quartz is both more physically resistant and more chemically resistant that feldspar. It's hard to say which is the greater factor. In some situations it may be one, while in another situation it may be the other. To a great degree they work together. Anyhow, more weathering of any variety would create a higher quartz proportion.
Moose
Edited by Minnemooseus, : Firefox was fighting me.

This message is a reply to:
 Message 108 by Dr Adequate, posted 12-11-2010 8:44 PM Dr Adequate has replied

Replies to this message:
 Message 117 by Dr Adequate, posted 12-20-2010 11:32 PM Minnemooseus has replied

  
Dr Adequate
Member (Idle past 284 days)
Posts: 16113
Joined: 07-20-2006


Message 117 of 121 (597346)
12-20-2010 11:32 PM
Reply to: Message 116 by Minnemooseus
12-20-2010 10:09 PM


Re: Mechanical (physical) vs. chemical weathering
Anyhow, more weathering of any variety would create a higher quartz proportion.
I meant a higher proportion of feldspar than there would be if the weathering was predominantly chemical, not a higher proportion of feldspar than quartz.

This message is a reply to:
 Message 116 by Minnemooseus, posted 12-20-2010 10:09 PM Minnemooseus has replied

Replies to this message:
 Message 118 by Minnemooseus, posted 12-21-2010 12:41 AM Dr Adequate has not replied

  
Minnemooseus
Member
Posts: 3941
From: Duluth, Minnesota, U.S. (West end of Lake Superior)
Joined: 11-11-2001
Member Rating: 10.0


Message 118 of 121 (597352)
12-21-2010 12:41 AM
Reply to: Message 117 by Dr Adequate
12-20-2010 11:32 PM


Re: Mechanical (physical) vs. chemical weathering
Some definitions:
Physical weathering - Breaking down a rock or mineral by fracturing or abrasion. Relative to feldspar, quartz is much more resistant to physical weathering.
Chemical weathering - Breaking down a rock or mineral (and essentially it is the breaking down of the rock component minerals) via chemical reactions. Quartz is essentially immune to chemical weathering.
Now, both types of weathering are usually happening at the same time, and one will tend to enhance the other. Physically breaking fragments into smaller particles increases the total surface area which enhances chemical weathering. Chemical weathering softens the material which enhances its fracturing and abrasion susceptibility.
Bottom line - It takes a lot of physical wear and tear to destroy a quartz grain.
Now, in the lab, it would be possible to isolate the material from chemical weathering and look at just physical weathering. Say, put 50% feldspar grains and 50% quartz grains in a totally dry tumbler and let it all tumble for a long time. What will you end up with? Rounded quartz grains and relatively small amounts of quartz dust, and feldspar dust. Of course, as mentioned above, that feldspar dust is now in prime condition for chemical weathering to kick in if water based solvents/reactants are introduced.
There are real world examples of (essentially) purely chemical weathered rocks. I'm not going to here get into such much, but see bauxite and laterite. In my quick readings of those cites, I didn't notice much specific mention of quartz, but I'm thinking that quartz is not much effected by the process (but I may be wrong).
Moose

This message is a reply to:
 Message 117 by Dr Adequate, posted 12-20-2010 11:32 PM Dr Adequate has not replied

Replies to this message:
 Message 119 by petrophysics1, posted 12-21-2010 7:46 PM Minnemooseus has replied

  
petrophysics1
Inactive Member


Message 119 of 121 (597475)
12-21-2010 7:46 PM
Reply to: Message 118 by Minnemooseus
12-21-2010 12:41 AM


Re: Mechanical (physical) vs. chemical weathering
Hi Moose and Dr.A.,
First, sand is a grain size. It has nothing to do with the mineral content.
Read that again. When I describe a sand I first say if is VF, or F, or M, or C or VC, or a mix in which case it is not well sorted. Then I descibe how rounded or angular it is, then how spherical.
At that point I would describe its color and then mineral content, fossils, cement, clay content etc.
When I say the word sand.......I AM ONLY TALKING ABOUT A GRAIN SIZE.
Mechanical weathering depends on the physical resistance of minerals, their hardness. Feldspars are not as hard as quartz, but quartz is not as hard as garnet.
So at the mouth of the Mississippi River why is there only quartz and clay and not garnet. The clays (as a mineral) are the result of chemical weathering, the garnet as well is gone, not because it wasn't hard, but because it isn't as resistant to chemical weathering as quartz.
Look up Bowen's Reaction Series. It shows you the pressure and temp minerals crystallize at, but it also shows you what minerals are less resistant to chemical weathering. The last mineral crystallizing at the lowest temp and pressure is quartz, and therefore the most resistant to chemical weathering at the surface.
Quartz does chemically break down, otherwise where would silica cement come from? Polycrystalline quartz sand grains weather faster than monocrystalline quartz sand grains. ( A sand grain looked at in a petrographic scope with crossed nicols will show different angles of extinction if it is polycrystalline, but if monocrystaline the whole grain will extinguish at once.)
One can see the mineral content of sands change, along with an increase of polycrystalline quartz as one gets closer to the source rocks/mountains.
There is no way a giant flood could have done this. We see it in sediments today, and we see it in the old rocks if we actually look at them and understand how they were laid down.

This message is a reply to:
 Message 118 by Minnemooseus, posted 12-21-2010 12:41 AM Minnemooseus has replied

Replies to this message:
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petrophysics1
Inactive Member


Message 120 of 121 (597479)
12-21-2010 7:58 PM
Reply to: Message 119 by petrophysics1
12-21-2010 7:46 PM


Re: Mechanical (physical) vs. chemical weathering
Not to confuse everyone but geologists use the term "clay" in two ways. One refers to a grain size like "sand" and the other refers to clay minerals which may not have been formed by abrasion of any kind. They were formed chemically, either at the surface or in situ in the subsurface.

This message is a reply to:
 Message 119 by petrophysics1, posted 12-21-2010 7:46 PM petrophysics1 has not replied

  
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