Walker River Delta, Nevada: 1994-2007

Dynamic changes on the delta of the Walker River. I made this simple movie with Google Earth, Snagit, Picasa, and YouTube. Took 30 minutes total.
 
Trying to develop painfully obvious illustrations for the need to create easily updatable and distributable maps of dynamic geomorphic settings. This is part of my odyssey to convince people to share data; contribute data to a single database (or coordinated databases); number their units in depositional order; and accept the fact that geologic maps of active systems require continuous updates. 
 
Note: width of each image is approximately 1.75 mi.
 

State of the Walker River Map....the end (for now)

Moving on, finally. The two images below show what the map looked like on October 1 and what it looks like now (after ~100 hours of mapping and GIS work since 9-30-09). The (pen)penultimate map shown here illustrates the location of contacts presently attributed as 'intraformational' because I was unable to consistently divide them across the entire map in time. Map now goes to NBMG cartographer who will find many problem areas, require additional input from me, but ultimately generate a nicely laid out product. That will be the next post in the series....at the end of October....if I survive GSA.

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State of the Lower Walker River map: October 13

Nearly finished. Most polygons fixed (there is one major leak...ack!), although many Holocene fan units have been lumped for now. The underlying map is considerably more complex, but cannot live up to it across the entire map, so it remains somewhat general for now. Added lacustrine bar symbology to reduce monotony in the 'beach blankets'. Have to stop working on it tomorrow AM. 

It is actually more fully realized than the better-looking image in the previous post, but I had a massive ArcGIS fail that forced me to rebuild the color sheme, etc. Ran out of time to annotate. Such is the constant battle with ArcGIS...freaking powerful program with some dreadful idiosyncrasies.

Amazing what a geologist who is self taught in GIS can do in less than two weeks, no? If I can do it, anyone can.

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Lower Walker River map: October 11

Eight more hours, on a Sunday with great weather no less. Map is close to 'good enough for now'. It is boiling down to all of the small, complex areas and is looking pretty good overall. Only a few glaring glitches to fix if I have time. Otherwise, will emphasize 'Preliminary' in the title more than usual. 

What I have now is a really good map to take in the field for detailed scrutiny of complicated areas. Also a serious conversation starter for my co-authors-to-be who will have lots to say about it.

It is one of the more complex maps I have worked on ever, and most of the complexities are related to either the interaction of active faulting and the ups and downs of pluvial lakes throughout the Quaternary; or to tremendous changes in lake level and river planform in only the last 100 years. That's right, the most intricate areas to map are historical in age. 

Heading home for a bike ride with the family...

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Walker River Map: October 10

Yet another weekend away from the family desperately trying to cram a 3 month map production effort into a couple of weeks. Yes...losing my sense of humor. Need to head home.

The map is nearly at a point where I can comfortably submit it as a reasonable representation of what is on the ground out there. Included here is a snippet at 1:24k and an overview at about 1:75k.

Probably finish tomorrow.

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