Ice block while diving

[DetectorGuy]

I saw some Ice diving photos from Europe that showed divers pushing the triangle ice block under the ice. The last diver would push the block about half way under the hole and then crawl up on it and out of the hole. The block would be then be slid into the hole the rest of the way from on top. This seems like a completely dangerous way to do things. The tether rope could and would get snagged on this submerged block of ice and possibly pull the block back into the hole trapping the diver. Not to mention if the rope gets snagged on this submerged block the rope tender would not have an accurate sense of where the diver actually is. Has anyone ever used this method of temporarily storing the block of ice underwater? I hope not...

[SmithDiving]

Always a no no to push the block under.  Not only does it create an entanglement problem but it can freeze to the bottom of the ice and then you can't use it to fill in the hole after diving.

[grumpie]

Ice block can be left in the hole and on the pointed side of the triangle towards shore and used as a guide for the tender. name the four types of ice.
1
2
3
4
What are some of the common actions that will cause week spots in ice.
1
2
3
4

[DetectorGuy]

[quote author=grumpie link=topic=5181.msg28495#msg28495 date=1229223046]
Ice block can be left in the hole and on the pointed side of the triangle towards shore and used as a guide for the tender. name the four types of ice.
1 Anchor Ice
      Submerged ice attached or anchored to the bottom, irrespective of the nature of its formation.
2 Black Ice
      Transparent ice formed in rivers and lakes.
3 Border Ice
      An ice sheet in the form of a long border attached to the shore.
4 Brackish Ice
      Ice formed from brackish water.
5 Brash Ice
      Accumulation of floating ice made up of fragments not more than 2 metres across; the wreckage of other forms of ice.
6 Candle Ice
      Rotten columnar-grained ice.
7 Columnar Ice
      Ice consisting of columnar shaped grain. The ordinary black ice is usually columnar-grained.
8 Consolidated Ice Cover
      Ice cover formed by the packing and freezing together of floes, brash ice and other forms of floating ice.
9 Corn Snow Ice
      Rotten granular ice.
10 Deformed Ice
      A general term for ice which has been squeezed together and forced upwards in places /and downwards/. Subdivision are rated ice, ridged ice, hummocked ice, and other similar deformations.
11 Dendrites
      Thin branch-like growth of ice on the water surface.
12 Drifting Ice
      Pieces of floating ice moving under the action of wind and/or currents.
13 Dynamic Ice
      Pressure due to a moving ice cover or drifting ice. Pressure occurring at movement of first contact termed Ice Impact Pressure.
14 Flooded Ice
      Ice which has been flooded by melt water or river water and is heavily loaded by water and wet snow.
15 Frazil
      Fine spicules, plates or discoids of ice suspended in water. In rivers and lakes it is formed in supercooled turbulent waters.
16 Frozen Frazil Slush
      Accumulation of slush that has completely frozen.
17 Granular Ice
      Ice made of granular ice grains.
18 Hanging /ice/ Dam
      A mass of ice composed mainly of slush or broken ice deposited under an ice cover in a region of low flow velocity.
19 Hummocked Ice
      Ice piled haphazardly one piece over another to form an uneven surface.
20 Hummock
      A hillock of broken ice which has been forced upward by pressure.
21 Ice Bridge
      A continuous ice cover of limited size extending from shore to shore like a bridge.
22 Ice Jam
      An accumulation of ice at a given location which, in a river, restricts the flow of water.
23 Ice Run
      Flow of ice in a river. An ice run may be light or heavy, and may consist of frazil, anchor, slush, or sheet ice.
24 Ice Sheet
      A smooth continuous ice cover.
25 Ice Twitch
      Downstream movement of a small section of an ice cover. Ice twitches occur suddenly and often appear successively.
26 New Ice
      A general term for recently formed ice which includes frazil ice, slush, shugs/sludge/, and other types of ice.
27 Pancake Ice
      Circular flat pieces of ice with a raised rim; the shape and rim are due to repeated collisions.
28 Rafted Ice
      Type of deformed ice formed by one piece of ice overriding another.
29 Ridged Ice
      Ice piled haphazardly one piece over another in the form of ridges or walls.
30Rotten Ice
      Ice in an advanced stage of disintegration.
31Sea Ice
      Any form of ice originating from the freezing of sea water.
32 Shale Ice
      An accumulation of thin broken plates of ice formed when skim ice breaks up.
33 Sludge
      An accumulation of spongy ice lumps formed from compressed frazil slush, snow slush, or anchor ice.
34 Skim Ice
      Initial thin layer of ice on a water surface.
35 Snow Ice
      Ice that forms when snow slush n an ice cover freezes. It has a white appearance due to presence of air bubbles.
36 Tabular Ice
      A particular type of ice whose grains have large horizontal dimensions.
What are some of the common actions that will cause week spots in ice.
1 Current
2 Insulating snow cover
3 Dynamic pressure
4 Wind
5 Heat/Melting
6 Husqvarna with 36" bar
7 Some mother-in-laws



I do better at multiple choice... but I am sure the answer you were looking for is in there some where.
I think I remember you telling me: Shale ice, Black ice, Skim ice, and I think Granular ice.

[DiverQueen]

Common actions that can cause weak spots in ice:


Actions of schooling fish!

Springs and underwater currents!

[arcFlash]

summer

[grumpie]

you guys are on top of things, or should I say under things
grumpie

[DetectorGuy]

Being that it wasn't for a test, I took the liberty of asking Mr.GOOGLE for help. What was the water temp in the river today? Was there chunks of Ice coming down stream?

[grumpie]

there was some ice flows and water temp was about 35 degrees. the current was about 2 knots. it could be dove if we had to.

[grumpie]

DQ how about decaying weed beds, current flowing over reefs or rock piles,