effects of heavy water on fields and meadows ?

[galoshers]

i was just curious after watching TV news as to what the effect of say 2-3-5 feet of water on a field would do to coins and artifacts  ?
as its seeps down thru the layers would it take lost items to deeper depths ??
or are they stuck at the same level depending on soil or clay conditions of the field of course .

[Dryland]

Thats a good Question, I have permission on land that gets flooded every now and then, The soil is like river silt and I'm digging cans out at over 12 inches, I presume it's because the water takes
things deeper ?

[Chef Geoff]

Water in itself won't make things go deeper as that would involve the ground undergoing liquefaction as the same force of gravity/weight of water is acting on the ground as it is on the coin.
An item close to running water does move downwards by being heavier than the surrounding soils and thus stays in one place while the soil around it is washed away, this soil s then replaced with new silts, thus the item appears to have sunk.
This can only happen if the force of water is enough to move the soil but gentle enough to leave the coin.

[DEADLOCK]

Think another theory is the layer of Silts that is deposited when flooded that lie on the top of the soil. Every time it floods it all adds up.

[carling2]

my expriance is that flodplains can be very quiet but it depends on where site is then it becomes like normal land rules , more activity =more finds and I also find the heaver items are usually found ie, pot legs,spindle whorls , lead etc,, maybe they give the most resistance ?

[Chef Geoff]

Not more resistance as things don't sink they get covered but those items have a better target profile and so a better signal

[Christoph1945]

Think another theory is the layer of Silts that is deposited when flooded that lie on the top of the soil. Every time it floods it all adds up.

Hmmm, that sounds about right!   

[galoshers]

that may explain my field that gets flooded and has tons of history on it but nary a signal

[Pon]

i was just curious after watching TV news as to what the effect of say 2-3-5 feet of water on a field would do to coins and artifacts  ?

I dont see the water making any difference to find depths, Flood plains are exactly what they say they are, no one in their right mind would build on one, so the amount of precious metal that is lost is going to be greatly reduced. I would have thought most flood plains would fall into the "casual loss teritory"
The sea is one huge flood plain...(sort of) Divers still find wrecks from 2000 years ago and thats with hundreds of feet of water pushing down on them.....
*Edit*  Being just a simple Black country kid, my logic is probably way off the mark.  

[Chef Geoff]

It depends on the drainage management in history, as I've said there are many buildings and roads across the Somerset levels that are now meters below the present ground level. A few years ago Wessex Water were reinforcing the banks of the river Parrett and they found the Roman surface along with a landing jetty all at 3 meters below the current surface.
After the Romans left the sea defences were left to fall into ruin for almost 600 years until the arrival of the Benedictine monks at Glastonbury by which time the tides had come and gone nearly half a million times and each time would leave sediment.
Also the lake villages at Glastonbury and Meare are built on man made islands so what you see isn't always what it seems

[Dale]

It depends on the drainage management in history, as I've said there are many buildings and roads across the Somerset levels that are now meters below the present ground level. A few years ago Wessex Water were reinforcing the banks of the river Parrett and they found the Roman surface along with a landing jetty all at 3 meters below the current surface.
After the Romans left the sea defences were left to fall into ruin for almost 600 years until the arrival of the Benedictine monks at Glastonbury by which time the tides had come and gone nearly half a million times and each time would leave sediment.
Also the lake villages at Glastonbury and Meare are built on man made islands so what you see isn't always what it seems

We think 3 meters seems a lot of sediment but its surprising what the sea/rivers can drop off.......I was working in Fleetwood near Blackpool on a very large green waste project beside the river Wyre, one day it decided to burst its banks and dropped off 4-5inches of sediment over the whole area, 1000's of tons! it was to much to get rid of, we just stoned over the whole area and raised the levels.


 

[Dale]

If you dropped the Somerset levels now by 3 meters I think we would be in a right mess at the moment with all this rain...... The Romans did some great things in our country, controlling the somerset levels must have been a big job??

[markld3]

hi all, I've been thinking (never a good sign)  after reading this thread and others on beach detecting, Looking at some fields where I live there is a distinct route the water follows across them, now this happens every time we have either heavy rain or prolonged  spells of rain, so would it follow that any items might get moved along the field over a period of time and end up being dumped at a low point where the water collects, I'm thinking maybe items in the top 2 to 4 inches especially in fields where there is livestock churning things up, anyway just a thought 

[ysbytymike]

Spot on Mark. Good area's to search, although, don't discount the slope area's.
As you say, gravity and soil movement (be that ploughing or cattle) over the centuries will help with the movement, so there might still be stuff
on the slopes making its way down to the lower levels. Water just increases the speed this process happens. 
Ysbyty

[carling2]

f you look on the enviroment agency flood maps the flood plains are marked deep blue{ where it always floods} and light blue {where it floods in
sevear weather,, I find the light blue areas can be good places to search as there seems to be a concentration of finds in those areas.