Apr 28, 2010, 03:31 PM
Sink Rate in the South
Ok, I posted this below in another forum dedicated to the E-trac. Please excuse all the content about the Minelab, I didn't post here because of the brand of detector I use. Rather, I wanted some feedback regarding the sink rate down here in Grand Bay, AL. It seems with all the rain we get historically that it is easy to believe that the old coins are deeper here than in other places. Anyway, I hope to here from someone down here that can give me some neighborly perspective:
[bg=http://forum.treasurenet.com/images/coinsc.jpg]I'll admit it, I'm Struggling...
Posted by: wharghoul [ Send a Message ]
Date: April 22, 2010 01:04PM [/bg]
I've been working with the E-trac for about 2 months now (around 50 hrs.). To date, I've found two worthwhile finds: a Spanish Reale and V Nickel. (and a bunch of wheats, modern clad, and trash)
I'll be the first to say the operator of the machine is the primary reason for the lack of quality finds. However, I'm an intelligent enough guy and I've read the manual and Andy's book enough times that I know it isn't just me.
It could just be that my coils (6x8 SEF, Pro Coil, 10x12 SEF, 12x15 SEF, 15x18 SEF) aren't passing over any silver coins. Fair enough, but I'm hunting some school yards, churches, homesteads, and even an old bank that goes back to the late 1800's, as well as one area that goes back to the mid-1700's (where I found the Reale).
I'm inclined to think that there are a few other major factors besides my inexperience that have thwarted my efforts.
First, most of my spots are littered with iron and trash down to about 6". I realize my situation is not unique in this regard. All my older wheaties that I've found have been in this range. In fact, I've never dug a coin over 6" and that includes the Cortes and CZ70 that I used for about a year before buying the E-trac. On a side note: my auto +3 sensitivity rarely goes over 23.
Secondly, (and I think this is where my situation might be a little more unique) the sink rate in my area seems to be a little more dramatic. I live in South Alabama, about 1 mile inland, and this region (New Orleans to Pensacola) gets more yearly aggregate rainfall than anywhere else in the Continental U.S.(55-60") Couple this with mild winters where the ground doesn't freeze and I'm finding 2004 coins at 5-6" deep. Hell, I've found budweiser cans at 8+" deep and they don't appear to be that old. I'm almost certain that no new soil has been added to these areas.
So here's my theory, all of the newer stuff (modern clad and trash) is within the first 6" of soil. The older coins, due to the sink rate, are generally beyond 12" and past the detectors capabilites. Either they're too deep for the E-trac or I just can't see through the trash to see the deeper targets.
I'm not just cherry picking for good targets, I'm digging tons of iffy signals and some bad signals (10-25's, 12-02's, etc...) too just to learn the machine.
I hope that someone from this area will set me straight on my theory and tell me that's it's just my lack of experience with the E-trac and detecting in general that's the main culprit in my lack of finds. That would actually be a relief, because I know I'm going to get better and finds could increase.
I'm just really getting discouraged and lurking just isn't cutting it anymore.
Apr 28, 2010 03:31 PM
Jul 04, 2010, 04:56 PM
Re: Sink Rate in the South
Haven't been detecting too long and I don't use an etrac but here in Mobile it isn't odd to find a memorial penny 5"-6" deep but I've also dug a 1912 V nickle at 3" and a 1902 dime at 5". I've dug about 25 wheat pennys and all have been 6"+ so based off of my limited experience I would say the rainfall probably has something to do with coins sinking in the ground faster than normal.
Aug 05, 2010, 07:39 PM
Re: Sink Rate in the South
hello wharghoul, i see i'm not the only one with the same thoughts that you have. i have also found the zinc pennies down to five inches and wheaties at 1/2- 2 inches. and like you say no soil added. i came to the conclusion that our state was very slow getting started after the civil war. people here did not have what the yankees had as far as money.
i also have noticed the differences in the soil and still can't find a solution to why i found a half dime in sandy soil at 1 inch and another place with harder ground, coins deeper. i was thinking that the coins were too deep for my sovxs and bought a 15'' wot coil for it and never found anything any deeper. just a mystery that will hang in for a while.
Sep 21, 2010, 04:00 PM
Re: Sink Rate in the South
I don't think there's any guarantee with a sink rate theory. Here in Pensacola, I've found colonial buttons, cut Spanish silver coins, buckles, etc. as little as 2" under the surface. Alot of it depends on the history of the area you're hunting in addition to the type of soil. Since much of our soil over here is a quartzite sand/clay mixture, the amount of overburden is going to depend on the history of vegetation and erosion on the particular spot - assuming there's not been any land development in that area.
There's a particular Spanish encampment from 1781 where they cleared the surrounding site of vegetation down to bare sand prior to the setup of the camp. They were on the site for over a month and the site was cleared again 30 years later for Andrew Jackson's army. Over the years, the surrounding area was allowed to re-vegetate thus adding a good layer of organic matter on top of the sandy layer. During a recent hunt on a historically vacant lot, we found relics from that period right below the sandy layer (within an inch). In other words, it was more a matter of 200 years of decaying leaves and other vegetation that created the overburden material rather than an amount of 'sinking'. Does that make sense?
Just something to think about.
Sep 23, 2010, 09:33 AM
Re: Sink Rate in the South
Thanks for the responses,
I have to say, my theory came at a time when I was extremely frustrated. I had gone 6 months (at least 300 hrs) with no silver. I was about ready to give up the hobby. I knew the Etrac was a great machine, or at least that's what I kept telling myself to justify the $$$ spent...
Well, sold the Etrac about 4 months ago and got my money back out of it. One last ditch effort, swore that I'd give just one more detector a chance and if the action didn't' pick up that I was going to pursue another hobby. It really made me sad to think about quitting mding, I hunt primarily at night and I really enjoy the peace that it brings me.
So, got a great deal on an F75 ltd. I had done months of research and figured if this detector couldn't get down to where the good stuff is, nothing can.
It has made all the difference in the world. Spots that I had completely lost confidence again came alive. I'm now accustomed to getting at least 1 silver every time out. I don't usually find anything really old, but the roosies, mercs, wheats, and buffalo nickels are popping up quite regularly.
I know the Etrac is a good machine, there are just too many people making great finds for it not to be so. However, I really think the multi-frequency just does not go as deep in this soil as a good single freq. detector.
With my previous 4 detectors, my deepest finds were in the 5-6" range. Now, I commonly dig 8-10" targets with the 11" biaxial coil. I dug an old pull tab in clean ground the other day at no less than 14". I was blown away, although I thought for sure it would be something good...
My fav. coil is the 5" DD. That thing regularly pulls coins from 6-8" deep and I can hunt in extreme trash with it. I dug a wheat cent last night at a good 8-9 inches. It was embedded in the bottom of the hole and the butt of my propointer was even with the top of the hole.
So, in conclusion, I'm in love with this hobby again. I would love to find a half-dime or an old copper one day, but at least I know now that I've got the right tool for the job and I'm confident that if my coil ever passes over one that I'll get a chirp at least. Now I just need to get the permission to hunt some of those older spots that might have some of those real oldies.
Take it easy,
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