wave action and sand

[jerry123]

I was wondering if sand is pushed up on beach or pulled out after storm and high winds? The sand is down to bedrock where I metal detect after storm.
Not sure if coins and jewelry is pushed in or pulled out? I wade out chest deep and nothing but bedrock. Always been atleast 1ft deep sand as far as I can wade out.


Thanks Jerry

 

[Cupajo]

Many factors come into play jerry.

Prevailing currents, wind speed and direction, depth of water, exposure to open ocean, composition of sub-strate (boulders?, cobble stones? seashells?, clay?) are some to consider.

There are places locally where sand may drop 6' over night with the right conditions.

Frequent scouting of your hunting area with these things in mind can really fill in the gaps and give you an edge over your less knowledgeable friends.

GL&HH Friend,

CJ

 

[OldBeechnut]

Lew Nailed it with......
Frequent scouting of your hunting area with these things in mind can really fill in the gaps.

Quote Seaweed (Ray Midgett)

NC's beaches are going through a constant (sometimes almost daily)...stripping, eroding, rebuilding......stripping, eroding, rebuilding...process....until ....around Jan. or Feb. the erosion process...has gained on the rebuilding... which usually follows.....to the point where the beaches have reached their lowest point of erosion. During March and April, the rebuilding cycles will outgain the erosion cycles..until early May....when the summer beaches will begin to rebuild. OK!!!!!...the trick to winter beach metal detecting.... simply is to catch the beach...during those prime winter months (Sept./April) ...when the erosion cycle is occuring!!...Simple enough.....watch the weather, the wind direction, the times of the tides, the time of full moon (important!!), WATCH THE BEACH!! A beautifully eroded beach can be totally ruined by just one 'high tide'.. on a beautiful winter day!!.....one or two inches of new sand may be all it takes to turn a 200+ coin day.....into total ZILCH HUNTING!!..."You should have been here yesterday!"...applies to beach metal detecting, just like it does to fishing!!

http://www.outerbanksnc.net/beachtips.html

 

[jerry123]

Thanks for the replies,
What I really want to know is after high winds and big waves and all the sand is stripped away down to bedrock where I hunt.. Is all the sand and goodies pulled out and lost in deeper water or is it pushed in up on beach?


thanks for your help

Jerry

 

[BigDan]

About three weeks ago I hunted a large ocean facing beach on Outer Cape Cod the morning after a wind storm passed. There was a five foot deep cut as far as the eye could see. This beach has thousands of patrons daily. I found only 1 dime in a 2 hour hunt at low tide. I thought it would be loaded with targets. NOT SO ! My presumption was that the targets were all pulled out into pockets in deep water due to the wave action. The targets will stay there as there is a resident population of Great White Sharks at that patticular beach. I stayed on the wet sand ! Another detectorist I met was having the same results.

On a prior hunt on the same beach 5 years ago the beach was producing many old targets and a Gold Eagle Coin was found. My conclusion is that sometimes the targets are removed with the sand and sometimes they are exposed. You just have to hit the cuts and find out

 

[dewcon4414]

Again..... weight, surface and density comes into play. Gold is 10 times heavier than sand it sinks to equal densitiy unless something stops it like hard pan. Most will settle to lower areas if moved depending on the strength of the current. Then get covered quickly. Thats why you hit it hard when you get those natural movements to hard pan.... better known as cuts. Water movement is very powerful especially when shallow and forced. In the winter here on the Gulf sand moves around a lot. You can get hard pan today..... then bam in comes the sand to cover up all those drops or old targets AGAIN. They didnt move they got covered up.

Dew

 

[Tom_in_CA]

Big-dan, another explanation for this phenomenom (of great-looking cuts, with no targets beneath them), is because the sand that is being cut out, is STERILE to BEGIN WITH. You know, like last springs build up, where sand had come back in, (yet without targets coming back with it). So that the sand that is being cut out now, is sterile. The reason I think this is often the case in those situations, is I have sometimes even seen, at the base of such cuts: fixed objects that I know for a fact that I saw the previous season. You know, like fire-pit debri, wooden fixed objects, sewead that's not even corroded yet sticking half-way out of the cut (evidencing only 6 or 8 months of having been buried), etc... So it depends on if the sand that came back in, on that particular zone, had targets coming back in with it in the previous buildup. Sometimes targets come back in, other times it's just sand-alone. So your cuts aren't happening in the better sand, NOT that the targets are pulled out into deeper water with the sand.

Ok jerry123, my take on your question, is coming from my CA experience (so not sure if it applies to your east coast beach): When we get erosion going on here, think of it as mother nature's giant riffle board, or sluice-box effect: the lighter sand is being washed out. And the heavier metal targets are moving slower in that out-motion. Hence they are scattered about on certain parallels, where they've "lost steam". No, they aren't getting "thrown up". They are "going out". And yes some, or all in certain cases, can go all the way out too. In which case they don't necessarily go way the heck off-shore, but might merely be in the rip-curl wave-break section of the beach. Then they come back in slowly, during the calmer season buildup season.

I've even seen freak conditions (real fun to work), where the beach is litterally stratified by weight: The lightest weight coins (dimes, and pennies) are nearest the cut. Then a little below that, is the nickels and like-weighted things. Then a little below that is the quarters and such, and then down closest to the water, is the halves, fishing sinkers and gold rings But that is very rare. Most of the time it's just parallel band somewhere between the cut and water's edge, where no targets are above that line, or below that line.

Another freak condition I've seen a few times in my years (but only about every 5 to 7 years) is where it erodes down to bedrock in some spot. And the targets can be so fast and furious, a 400+ coin day (in just a few hours) is possible. That's litterly multiple coins per scoop, as fast as you can dig. But if your beach ROUTINELY gets eroded down to this level (ie.: has "acclimated" to this pattern), then .... no .... bedrock may not be that good.

 

[ratpack]

Well said Joe, you are right no the money

 

[GeorgeinSC]

In my area of South Carolina the ocean tends to move sand down the beach from north to south. If the northern area of an island is eroded a lot of the sand will migrate towards the southern end of the island. Hurricane Sandy moved a lot sand and piled it up as sand bars out from where the waves usually broke. Now we have the beach, a lower area that may or may not contain water at low tide and then the sand bar that is exposed at low tide. So far I have not found anything but Zinc pennies on the sand bars. The current moving down the beach makes it difficult to keep your sand scoop on a target when one is found.

 

[Kossie]

When considering wave action, objects are mainly moved by the surf. The force of a crushing wave perpendicular to the coastline is the most powerful force. The pulling force of the retreating water flow on the beach slope is significantly weaker. Whether an object is tossed up on the beach or moved out depends on size, shape, density and orientation of the object. This determines the specific resistance to movement of the object. Just basic physics. Under low to moderate wind conditions sand will be sedimented on the beach. The onshore wave actions is to weak to transport heavy objects. These objects will be buried deeper. In shallow water sand can be removed from underneath the heavier object since sand is immediately brought in the object will be buried just a little deeper in reference to the starting point after each wave until the object has sunk to deep for those waves to pull sand from around it.

In high-wind and storm conditions a threshold value for the objects resistance to movement can be exceeded by the wave action. Overburden can be stripped fast to deeper water. The heavier objects can be moved and tossed on the beach. If the object is tossed high enough one the beach slope the retreating water may be to weak to pull it back in the sea. However the back-flow can still be strong enough to erode the lighter sand under and around it. Often these objects are pushed up and dragged back for a while. If have seen a sorting of coins on a sandy beach slope but this is especially evident on a beach with pebbles. The coarse pebbles or cobbles are sedimented where energy is highest and finer pebbles are tossed up higher where energy is lower.

What makes it more complex are factors such as the angle under which the waves hit the beach, beach slope (angle), rip currents, water depth, geometry of the coastline and sensitivity for interference of wave, tidal range (the surf is moved up or down the beach slope), the presence of objects that can cause increases or decreases in current velocity and wave action. These factors can cause exposed heavy objects to be dragged out to deeper water.

 

[GTzer]

Nice info. I'll just add-if you are down to bedrock-check any crack or holes or "bowles. Always the possibility that heavy metals could be trapped in those spots.
Make a mental note where they are located and check again as sand gets pushed back in-especially if it is a rough surf that does it.