I found the attached diagram with an article in Le Figaro. The diagram helps one to understand the situation of the trapped miners
a little better. It shows that this is a walk-in mine, not one with a shaft and winder. There are two roof falls in the access tunnel, one of which has also blocked a ventilation shaft that might otherwise have been used as an escape route. Questions remain though. I still do not understand why they are drilling from the surface, rather than clearing a way through the blockages. The article says that the tunnel was weakened by recent earthquakes, so that might explain the reluctance to go in that way, but why were the men working down there if the tunnel was weakened. Are we to understand that it was not inspected after earthquakes in the region? Also, why is there no escape shaft already in place? The mine owners have some explaining to do, in my view
Boadicea's Chariot 
Tom – would you take the trouble to translate 1 to 6, thanks, hough I do get the drift of it pictorially. It is a sorry business and I find the thought of their plight really quite upsetting.
FYI
Should you consult the USGS site you would see that the area is beset by earthquakes on a virtually continuous basis up to level 5 with occasional bigger ones. These are a fact of everyday life and do not actually impinge on people’s lives. So much of the Pacific ring is like this. No country could possibly keep running round checking this that and the other (at least, not until it falls down!)
Not even the USA spends money quite so profligately.
People in the UK and Europe just have no concept of how others live in continual earthquake zones.
We have a minor fault about 4 miles up the road that carries on continually at 3ish, all the concrete pads round houses here are cracked and most have given up years ago having them replaced!
But we do have earthquake insurance that is never carried as part of ordinary household policies here. Insurance companies do not want to carry the risks of anything that is likely to happen!!!
Northern Chile is an area that exclusively earns its living by mining various minerals, there is no other employment of consequence in the desert areas, so I expect it is a risk that is considered acceptable by society. Chile is a rich country these days since the socialist depredations of the 70s it has made a remarkable comeback.
these poor guys are going to be stuck down there for months by all accounts. I think it would drive me to suicide.
As for checking safety etc I would have thought it is all down to costs in money as human life is cheap.
Pap, the two red splashes (1) show where the falls are, the lower one having damaged the ventilation shaft, which could have been a possible escape route. 2 is the shelter the men are in, and we can see that press reports that they are confined there are misleading. 3-4-5 is the route of the probe which found them, and is now being used for supplies and communication. 6 is the planned drilling of a hole big enough to lift them out one at a time.
Christina, expecting an inspection of the only tunnel after an earthquake is not asking them to run around here, there and everywhere. That tunnel should be checked frequently as a routine.
It probably is visually. Not going to tell you a lot in certain rocks. We have not been informed as to the strata to my knowledge.
You would need a seismologist in residence virtually!
Were there any obvious cracking etc the miners themselves would have known, this is the route they access/exit the mine every shift. They would know it, as you would the street you live in. Nobody would be fool enough to go down if there were obvious changes apparent.
I do not think blame can be apportioned as yet, if ever.
Christina, miners travelling to the workface in groups can easily walk past a sign that things are wrong. They would probably be in conversation, or half awake. An inspection requires a man to walk the tunnel, undistracted by others, looking specifically for signs of movement. Movement occurs in all mines, and does not require an earthquake. These men will presumably have had a supervisor who could conduct such an inspection. It does not need a seismologist to spot tell-tale signs of movement in the supports. You are right not to blame any individual, but this mine is a high risk job. Higher than necessary, without adequate thought given to escape..
Tom, I appreciate that, thanks. I was half an hour down a gold mine in Obuasi, Ghana. The worst thing was the lift shaft itself – I think I went down 13 or 15 levels, though there were zig-zag tunnels running down to level 7 in which cars could travel. If the lift (more like a box) had stuck, I would have shot myself, except I didn’t have a gun. (I had to sign a disclaimer to bar myself and family from suing the company in the event of accident or fatality.)
God, poor guys. At least they’re in with a chance…
I’ve been on Le Figaro website today – looking for French A level material, but must have missed this.
Having only heard radio reports and no TV on this the picture really helps. Thanks
Well they are alive but how they will survive that length of encarceration, I can’t imagine. Nightmare scenario doesn’t really cover it. Good graphic, thanks.
There has been good coverage on CNN for those of you who get cable/satellite TV.
http://www.cbsnews.com/stories/2010/08/25/world/main6803732.shtml
This site may be of interest to you.
My opinion is rather re-inforced about the incipient fall of rocks being detectable.
However, there have been a good selection of mine violations there. Notably the failure of the owners to install a safety ladder in the ventilation shaft which would have allowed them to climb half way up the entry ramp. But as that was subject to a cave in too it still wouldn’t have got them out.
Grim situation, just hope there are no more serious quakes before Christmas!