Freshwater Beach and "Black Sand"

[Monty]

Freshwater Beach and "Black Sand"

If you read my second outing and attempt at beach hunting and could read out all the BS, you will find that I had a heck of a problem with black sand.? I had noticed it before while swimming and boating but never gave it much thought.? This beach I went to on the lake this morning had several dozen stirps of it running in about 1/2" layers the entire length of the beach.? Apparently when the water level stays at a constant depth for a couple of days it deposits this black sand in strips. This is a flood control lake and the level is lowered a couple feet at a time in the summer. It played heck with my detector, a GTI 2500, causing a constant falsing every time I crossed one of these strips of black sand.? It acted just as if I had passed the coil over a shallow copper pipe or something.? Needless to say I had trouble getting a true reading and being fairly new to the use of my detector I couldn't figure out how to stop the falsing.
? As far as I can determine,? the problem results in a ground balancing error.? ?I should be able to manually ground balance, set the Fast Track feature on "fast", raise my coil about 2" higher than usual and eliminate at least the majority of the falsing?? That according to the manual, although it does not directly address black sand, just soil with an extraordinarily high ferrous mineral content.? Does it sound like I am on the right track or is there somethng else I should know?? I had some idea of the problem at the time but did not have my pocket size manual in my pocket ergo I didn't know how to manually ground balance.? ? Any suggestions will be appreciated.? JIM

 

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[northeast hunter]

Re: Freshwater Beach and "Black Sand"

LOL find a new beach

 

[Monty]

Re: Freshwater Beach and "Black Sand"

D'OH! It was so simple! Why didn't I think of that? JIM

 

[stoney56]

Re: Freshwater Beach and "Black Sand"

Like Keystone, Kaw hasa lot of black sand as well. Most of the swimming beaches run east to west and I've found the black stuff runs in ribbons about 3 foot wide from the normal waterline to about 4-5 foot inland. I will eithr work the water side for a ways out or work the moist sand back in. I found I can eliminate a lot of the falsing by turning the sens down to about 4 and run with the silencer in the on position. Most of the toys, hotwheels, etc are found in the wetter part as that's where kids tend to build their sand castles, etc.. Coins and such are more likely to be found in the dry areas along with tabs, foil, nails, and bottle caps. Yes the occasional gold is found there as well but most of the gold is found further out in the water. But the people here don't seem to lose as much as they used to for some reason or someone's beating me to it as I've only seen 2 people using detectors in the last year or so, with the exception of a club in OKC that came up one year and together they found 2 gold rings and one earring along with a few dollars in change. They were in chest to neck deep water which is way too deep for my machine.

 

[DiggerDude101]

Re: Freshwater Beach and "Black Sand"

Jimmileo


Have you also experienced hot rocks in your area......iron in the rock?
This happens to me at Tablerock Lake area......all rock beaches! Drives me crazy!!!!!!!!!!

 

[Monty]

Re: Freshwater Beach and "Black Sand"

I've only hit a couple of "hot rocks".? One of them was probably a meteorite but I didn't recognize it as such and threw it away!? The other was in a school yard and it just looked like any other rock yu dig up but it sure made my detector sing!? JIM

 

[Vrent]

Re: Freshwater Beach and "Black Sand"

quote author=jimmileo link=topic=18031.msg115985#msg115985 date=1122600101]
had several dozen stirps of it running in about 1/2" layers the entire length of the beach.
[/quote]

does the black sand cover the entire beach like a blanket? or is it in stripes?
I don't know anything about the 2500 I am interested to hear that you can ground balance it. I have a 350 and used to detect a beach where the water would register as iron, very polluted, but the old swimming hole did produce. I always set my notch discrim to blank out the water. if the stripes are narrow I would be tempted to ignore them, actually ignore is the wrong word, I would learn them and then if something about them changed I would dig. Do not know if this makes sense, but how much time do you have to devot to this beach?

the more you and your machine become a team the more you can ignore thinsg like black sand
another solution is do you have any other detectors, soem detectors work in places and conditons better than other

and htose hot rocks unless they look like coal slag or coke I tend to save em like the meteriote you think you tossed. also remember old silver lead etc comes in ore

don't think I helped you, but ....
HH Vrent

 

[Monty]

Re: Freshwater Beach and "Black Sand"

Since the lake is a flood control lake they drop the water level a couple feet at a time. If the water level stays at one level for a while it leaves a strip of the black sand. Since it's deposited the way it is it runs the entire length of the beach and may be as much as a foot wide. It is about a half inch thick. If the water is low it may have 5 or six strips of black sand. The prevailing south wind seems to have a great deal to do with it since the beaches that run north and south have very little. You can't ignore it because it acts just as if a metal sheet had been laid down every where there is a strip of it. Your detector gives out a loud shriek and the lcd screen goes bananas! I tried to detect between the layers but it acted just like a detector does when you get too close to a wire fence. I suppose I could turn the sound off and just go by the screen but that's about like running on all metal all the time and you can't even guess what your target might be. I'll figure it out and put up a post when I do. JIM