[meteorite-list] Using GIS for Meteorite Hunting and Study

[McCartney Taylor]

I, too, am a GIS person. Since Land ownership & GIS has just been
brought up, I have to take this one step farther and mention good & free
GIS packages.

Someone just brought up ESRI as a GIS progam, and I would like to
discourage people from using it.  ESRI gives you piecemeal crippled
software that you'll have to pay licenses for each piece you enable.
While there base 'hook' product is free, you can quickly spend $2500
getting the 'Basic GIS' which is just decent GIS (ArcGIS $1500 and
ArcView $950).  Then the extensions can cost $12,500 to bring you up to
a complete GIS system that gives you map webpublishing and db
interoperability.  All of that is about the same as what GRASS does, but
its free.

There are some excellent Open Source GIS programs currently available.
You can download these for free and have them running within the hour.
Quantum can quickly import your GPS data.  Both of these run under
Windows or Linux.

Quantum GIS --  Young, small, and runs fast on old machines. Think of
this as a 'dune buggy' of GIS.  Use this one first, if you're new to
GIS.
http://qgis.org/

GRASS GIS -- Mature, stable, powerful, but very complex.  Good for 3D
and 4D plotting.  Like if you wanted to plot a strewnfield thru a
mountainous area then do a time lapse flyby. Think of this as a diesel
MAC truck of GIS.
http://grass.itc.it/

There are a couple of other Open Source GIS packages, but they are
immature and not ready yet, IMHO.

On getting the basemap to use as your main layer, here's a starting
point.

http://www.gismonitor.com/data/index.php
http://seamless.usgs.gov/


Steps to take once you have your program and basemaps.
1. Load basemap into GIS
2. Load GPS finds into GIS.
3. Make sure you have all data layers on the same projection (like
NAD83)
4. Draw polygons of area searched!  Important to know where you've been.
5. Draw polygons of area you are ALLOWED to search.  Important to know
where you can't go.
6. Plot points of where meteorites where found.  High Confidence Data
gets a special symbol.
7. Plot point of historically found meteorites that you have low
confidence of where you think they were found.  You could even draw
small circle polygons to represent the 'fuzzy' find location.
8. Draw Line of best guess of upper limit of Main fall axis.
9. Draw line of best guess of lower limit of Main fall axis.  The space
in between is your best greatest statistical chance of finding more.

-mt
IMCA 2760

copyright 2008 - I reserve all rights to put some of this in my upcoming
book.