Brad,

If you have a raster with your single band, you could try something like:
install.packages("raster", "rgdal")
library(raster)
# load raster
r <- raster("band_7.tif")   # (otherwise, use brick() instead of raster(),
so you can pick your layer)

flare <- which(r[] > 99)
p <- xyFromCell(r, flare, spatial=TRUE)

plot(r, asp=1)
plot(p, add=TRUE)

Now, you'll probably need some cleaning. That could be performed by
something like

install.packages("maptools", "spatstat")
library(maptools)
library(spatstat)

d <- density(as.ppp(p))
plot(d)

Etienne

On Wed, Mar 23, 2011 at 10:10 AM, Brad Nesom <kidsmake6@msn.com> wrote:

> I am a complete newb and have no idea if I am asking the right question or
> if it is in the right place.
>
> I want to determine gas flaring (burning of gas from a stack at an oil
> well)
> on a satellite image. I have been told that using landsat 7 +ETM images and
> doing some raz-mataz with band 7 I could identify flares. Quote"*The flares
> are sharp spikes, running around 100DN higher than anything else in the
> image." *
> I am only smart enough to know that there is not a flare attribute in the
> image and figure I will have to convert the image value to some unit that
> will make sense. Then I assume (don't go there) I will have to classify
> those values to get a (maybe binary maybe not) palette that will show hot
> spots and everything else as "no value".
> I probably don't even belong in here because I can start R and that is
> about
> it.
> I have been lurking for a while but haven't had time to jump in to any of
> the tutorial.
>
> If anyone is interested in helping I will stop apologizing and do what you
> say.
> Thanks
> gisbradokla
>
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