7/19/15 Report - Do Crashing Waves Throw Coins As They Break? 130 Year Old Winchester Found In Desert.

Written by the TreasureGuide for the exclusive use of treasurebeachesreport.blogspot.com.

Real Wave Photo.

Now this is really cool.  Believe it or not this is an actual photo.  Beside being a beautiful picture, it shows something very interesting.

I'm not positive but I think the photo is a Clarke Little photo.  He is a surfer turned photographer.

I lost track of the source, but here are more of Clarke Little's beautiful wave photos. 

http://clarklittlephotography.com/


Take a good look at that photo again.  Do you see what is happening?  Look at the brown sand or whatever being sucked up into the wave.  That is what I think is very interesting.  It wouldn't be that apparent if you were just watching it happen, but when it is frozen in time like that you can really see it.

In my 7/16 post I showed this illustration.  Notice how the waves move in circles.  I've told before about how if you are floating in the deeper water, you'll move in a circle as a wave goes by.

As the wave gets in more shallow water the circles get flattened and turn into  ovals.

What you are seeing in the top photo is the bottom of the circle where the sand is getting sucked back into the wave.  The circle isn't completed here because the water is too shallow and the wave is breaking.

Just think about what is happening there.  First the top sand is getting sucked out and then the wave comes crashing down with force just in front of that.  

When the sand gets sucked up into the wave, as you can see in the photo, it is lifted, and then when the crashing wave impacts the sand with considerable force.

That happens time and time again as the waves come in, and each time in just a little different place.

A report by the Naval Warfare Center (http://www.dtic.mil/dtic/tr/fulltext/u2/a495574.pdf) says, Overall, average impact pressures from the breaking waves are greater in magnitude than the impact pressures from the non-breaking waves and average impact pressures tend to increase with increased speed...

OK.  We knew that crashing waves have considerable force.  I recently posted about blocks weighing tons being moved.

Big waves, as is obvious, stirs up a lot of sand, but in addition to the effect of crashing, there is also the sucking that we see in the photo.   Add that to a near continuous flow running along with the long shore current on a steep beach and a lot of sand and stuff could be moved quickly.

Adding in any undertow or backwash, the net effect will depend upon a variety of factors, including the "trigger" and "drop" points for specific objects, as I've said before.  

I think my understanding of how coins and objects get covered and uncovered is fairly complete.   I've tracked and observed how objects move in many situations, but I have never been able track the movement of objects within big waves and during storms.  I think I'm getting pretty close to a complete understanding of that part of the process too, which will explain how coins and things wash up at times.

Looking at the picture at the top of the post and how the sand is getting sucked into the base of the wave, I wondered if coins or other objects could get sucked up into the wave and actually thrown ahead with the water in a breaking wave.  I don't know about that, but considering how easily coins flip (turn over) in relatively little current, I wouldn't be surprised if large breaking waves could throw some objects.  Certainly they are blasted, lifted and moved, but maybe not through the entire cycle of the breaking wave.

In the photo, you can see some of the sand moving ahead with the wave.

It would only happen when the waves and obects are in shallow water.  That is one condition.  When the water is deep relative to the size of the waves, the bottom and objects on the bottom are not affected.

When we have storms, some waves are breaking on a slope rather than a flat bottom like we see in the photo.  I

I didn't really want to introduce the complication of the different types of waves yet, but I unintentionally just stepped into it.

Besides breaking waves, there are other types, such as plunging waves and surging waves.

According to wikipedia

A plunging wave occurs when the ocean floor is steep or has sudden depth changes, such as from a reef or sandbar. The crest of the wave becomes much steeper than a spilling wave, becomes vertical, then curls over and drops onto the trough of the wave, releasing most of its energy at once in a relatively violent impact. A plunging wave breaks with more energy than a significantly larger spilling wave. The wave can trap and compress the air under the lip, which creates the "crashing" sound associated with waves. With large waves, this crash can be felt by beachgoers on land. Offshore wind conditions can make plungers more likely.

That is as much as I want to get into that for now.

I've known for a quite a few years that coins wash up onto the beach.  There is no doubt about that, but perhaps large crashing waves can move sand and objects in even more dramatic ways than I previously suspected.

For a relatively thorough explanation of waves, you might want to look at the following.

http://topex.ucsd.edu/ps/trujillo_waves.pdf

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132 year-old Winchester rifle was found propped up against a tree in the desert.  Nobody knows what happened to the owner or how it got there.

Interesting story.

http://www.foxnews.com/us/2015/01/15/132-year-old-winchester-rifle-found-propped-under-desert-tree/

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It seem that the Treasure Coast is in for a couple more weeks of one-foot surf.  How long can this last?

Happy hunting,
TreasureGuide@comcast.net

9/7/14 Million Dollar Coin Found by Detectorist. How Objects Sink Very Quickly Into Beach Sand.

Written by the TreasureGuide for the exclusive use of treasurebeachesreport.BlogSpot.com.

Very Rare Coin Found by Detectorist.

I hope you enjoyed seeing all of the fantastic Treasure Coast treasure finds sent in by  Captain Jonah.  Things like that are still out there to be found.  If you didn't see them, you'll want to go back to the previous two posts.


The threepenny piece shown here was struck in Boston, Massachusetts back around 1652 and is one of the first coins struck in what would become the US.  The coin was recently found by a detectorist in England.  Nobody knows how it ended up over there.

The coin, expected to be worth nearly 1.5 million US dollars, was dug by a detectorist who did not know how rare and valuable it could be.  He put it in a jar and lost track of it for a bit.

The coin is a real rarity in any condition, but to top it all off, this one is in amazing condition.

Here is the link to the article about that.   I think you'll enjoy reading it.

http://www.dailymail.co.uk/news/article-2745782/Minted-Dug-Midlands-field-1m-perfect-US-threepenny-bit-time-Pilgrim-Fathers.html

The detectorist and landowner will split the proceeds.  The coin is not claimed by England because it is a single coin and not a hoard.  

I wish we had something more like their antiquities laws.

One of the things about this story that is very interesting to me and very relevant to any detectorist is that nobody expected such a rare US coin to be found in England.  Things don't always pop up where you expect them.  It is possible to find a rare coin from England or any other country right here on the Treasure Coast.  It doesn't have to be a US coin, or even a Spanish cob.  You just never know!

Many thanks to Peter H. who sent this link.  He is one of our detecting friends from across the big pond. 


My 9/4/14 post, which discussed how objects sink in beach sand, received the most +1s of any of my posts.  I'll continue with that topic today.

A few days ago I showed how moving water would suspend a layer of sand and cause a coin or ring to sink.  How far the item would sink was very much determined by how fast the water moved, and how much sand was suspended and moved by the current. 

As I showed in my simple demonstration, the objects sank down to a stable layer of sand and stopped there.  I didn't see any relationship between the amount of time the water and sand moved and depth other than the very short amount of time that was needed for the objects to reach the stable layer of sand.  After that the object sank no more.

If this was the only way that objects like coins and rings sank into beach sand, it might take numerous periods of rough seas for an object to eventually sink through enough layers of sand to reach bedrock.  That is not the only way that objects sink though.  There is another thing that causes objects to sink more quickly.

You might have read articles about objects sinking into beach sand very quickly.  I've read reports that seem fantastically unbelievable.  I have however observed something that makes objects sink more quickly than the type of currents I talked about a few days ago.

When I circulated water and sand in a cup, it took seconds for the test objects to sink a mere eighth of an inch.  However, when water was forced down on the sand, rather than simply circulated as a current would do, the sand was quickly suspended and the objects sank much faster.

Here are two very short videos showing what I am talking about.  The only difference between the two videos is the amount of water force.  Take a look.

https://www.youtube.com/watch?v=36tgNx9a8Fg

https://www.youtube.com/watch?v=ESSOdH78eic

The results were amazing.  In that one second or so when the water was on, the objects sank an inch or more.  The rate of sinking was many times faster than when the water was circulated horizontally as was the case in my previous experiments.

After turning the water off, I stuck my finger into the sand to find where the objects went and found them down an inch or more.  Each time I repeated this experiment, the results were very similar.  The more force, the deeper the objects sank.

It appears that the downward force of water disturbs sand to deeper levels and suspends sand more quickly than horizontally circulating water, and as a result the objects sank more quickly.

How does that apply to a beach?  Waves crash with a similar downward force.  That happens not once, but repeatedly.  Each crashing wave disturbs and suspends sand.

As the tides go in and out the waves will crash at a slightly different place.  That means a wide area will be affected during each tidal cycle. 

If you have ever observed how they build a dock in the river, you might have seen them pump water downward, pushing sand up and out so that the post can be inserted down to bedrock.  This is a very similar effect.  When the sand is being suspended by the forced water, the post is easily pushed in, but once the post is in place it remains very stable in the sand.  (Bedrock in the river is about six feet deep.)

So now I have described two different types of forces that make objects sink in beach sand.  One is the horizontal current that suspends and moves sand, and the other is the vertical force of crashing waves.

When a wave crashes, sand is suspended, then the water rushes in towards shore, carrying sand with it.

I observed this very clearly on a beach recently when the waves were crashing on a sand bar and a flat layer of sand was being washed in towards shore where it was beginning to fill a small dip.  The front edge of the moving sand was very obvious.  (That was the day my camera batteries were dead.)

I posted this picture of that same beach back in my 8/13/14 post, but now I have a much better appreciation of the forces, how the sand is moved and how objects sink.

Notice the red line where the waves were crashing.  The waves look big, but they were less than two feet on that particular day.  Where the waves crashed, sand was kicked up, very much like in the two videos above. 

Any objects under a crashing wave could sink inches, and maybe more. 

Add to that the fact that the sand would only partially settle before being hit again.  Some of the suspended sand would then be pushed towards shore where it would settle. 

After a wave, the water rushing back out is not moving with as much force as the incoming water and is met by more incoming water.

Another thing to point out is that in the situation shown in the illustration the waves are nearly parallel to the beach.  There is no angle to slice away beach sand.

After objects sink deeply, they will likely remain put until they are uncovered again.  If there is a storm and the water rises and the waves crash on the beach or near shore buried objects can be uncovered again.


On the Treasure Coast we still have a small surf.  There is some weather that has very slight chance of developing into a cyclone over North Florida and another disturbance that is still closer to Africa.  It won't get here for several days, if at all.

We'll have a small surf through most of this week.

Happy hunting,
TreasureGuide@Comcast.net