buried coins

[RTG]

This is a very off the wall question but was just pondering it today. How do coins, relics, etc. end up at different depths underground. Obviously the older it is the deeper ( in general...) Say someone in 1900 (just as an example) dropped a coin in the middle of a park, at the top of a hill, where rain runoff wouldn't really affect it. (I'm assuming). In other words, dirt wouldn't really be getting washed on top of it, like it would if it were lost at the bottom of a hill.
So, say this particular coin is found today and was about 5 inches deep (again, just as example). Is it that 109 years of blowing dust has just piled on top of it? Does it "seep" into the ground somehow. A combination of the two? Something else?
I know..... like I said, "off the wall"..

 

[Elton]

Maybe who ever posted it can copy it over to here..

 

[jim tn]

Gravity, of course, comes into play and everytime that hill is mowed grass clippings build up and in time turns into decay and dirt. HH jim tn

 

[Furious T]

Your question is a very good one, and pertinent to metal detecting. It is also a question that is sometimes important to consider. Jim hit the overlaying factor in mentioning gravity and top dressing, whether by man or nature. Other factors which can make an object such as a coin or piece of jewellery go downwards are the little creatures which live in the soil. Every time a worm, grub or microbe moves under the object it either loosens the soil or creates a cavity which allows the object to sink a bit further. Additionally, every time pressure is applied above the object, as by a shoe or boot with a foot in it, or the wheel of a car or truck (ie. when someone treads on it or drives over it), as long as the soil surrounding the object is soft enough, that downward pressure will encourage the object (with the help of gravity) to sink lower. The texture of the soil is another factor which will influence the rate at which an object will bury itself e.g. a ring will sink more quickly in sand or sandy loam than it will in packed clay or gravel. There may be other factors. but those are some that I know. HH Sapper.

 

[marcomo]

Good answer, Sapper.

It seems so obvious now, but I never really thought about the creatures in the ground and their contribution to sinking.

 

[Jeb NWR]

Many reasons ! but left naturally the heavier the Coin is ,the more it will sink.

 

[Willee - Texas]

Just my opinion but ... as grass grows around the coin it gets down to the topsoil.
Dead decaying grass cover it.
New grass grows and the roots plus gravity push the coin down into the ground.
Once past the depth of the grass roots I dont know.

How do rocks pop up on the surface instead of sinking lower and lower each year?
If gravity did it all ... then all the rocks would be deep in the ground.
Why are they laying on the surface instead of sinking in?

 

[RTG]

Those are all great answers! Seems to be just a lot of little things that add to the depth. The type of soil is a great point too. While digging in a park with nice soft black dirt, I find new coins at over 3" deep sometimes (like a 2001 dime...). However, at an old house miles away that has that hard red clay, I have found much older items like WW1 buttons and coins in the late 1800's as shallow as 2". So that really helps to make sense of it. This can be helpful when trying to determine how deep to expect to find things (somewhat) and adjust the detector appropriately. Thanks a bunch!

 

[killi]

a ploughed field for example???? whats a ploughed field,,,,a beach is allways turning new and old stuff up,for example Ive had roman coins right on the surface,,,in the local park ive had to dig 20cm for a new euro 10cent pice,the ground moves ,we all know that,, it also depends on the size of the object,,weight ect,,and how hard or soft the ground is,,,on hard ground most objects are on the surface you dont have to dig so deep,,,Ive had german pfennigs ca 1875 to 1940s milli meaters from the surface in local parks(hard ground)just go out and dig,and you will find out your self,its all down to experence,,,and the site you work on,be it a ploughed field,beach ect,,,,,go out and enjoy it and learn for your self,,,,,,good hunting

 

[larky]

Someone told me, that if you drop a coin on the surface, it will drop 4 inches every hundred years, depending on the soil conditions of course.