Marking survey-stations

[Wookey]

+++ Andy Waddington on Cave Surveying [03-10-22 14:01 +0100]:
> On Wednesday 2003-10-22 12:15, Roger Johansson typed:
> 
> > I've seen and heard of several ways to [mark permanent survey
> > stations], for example cairns, carbide
> > soot markings, bolts, etc, but they all seems to have some major
> > disadvantages. Cairns will not withstand running water or clumsy cavers.
> > Bolts are time-consuming to place and might make the cave look littered
> > (carbide-soot looks even worse).

<snip useful summary from wadders>

The 'best' solution really does vary with cave type, scale, location and
denizens. One effective solution I've used is nail varnish. It comes in
convenient and robust containers and it's easy to apply a small dot and
write clear numbers (every 5th station or junctions is the convention of the
German surveyors I got the idea from). The best (most contrasting) colours
vary with cave but I've found reds and greens to be good and yellow
suprisingly bad. It's main disadvantage is that some types are very smelly.

In very large caves re-finding any marker is always difficult. In Mulu (Borneo,
Malaysia) they mostly used cairns marked with waterproof paper notes. These
notes survived for several years and only a few of them have been eaten by
rodents. They probably have a half-life of about a decade.

Carbide lasts very well but is unsightly and random marks can often be
confused with survey stations.

I've tried tippex (correction fluid) in UK caves, but it is very easily
rubbed off and doesn't seem to last more than a couple of years.

My default in terms of compromise between speed/convenience, clarity,
refindability, visual intrusion etc is Nail varnish. Small drilled holes are
good for long-term refindability/major stations.

Wookey
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