The Silver Peak Range

Took a morning hike in the north end of the Silver Peak Range today
while driving from Tonopah to Reno. As is often the case, I was the
only one around in a spectacular place in the Nevada desert.

This park-worthy area includes a photogenic array ot tilted and
faulted Miocene and Pliocene(?) volcanics and sediments. Oh, and a
nice little aeolian causeway that funnels through part of it, and
plenty more.

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State of the Clark County map, March 25, 2010

This one is huge, huge. This map is the focus of the Nevada Digital Dirt Mapping Project. It has a team of as many as 10 (now) at any given time. Two of us are 'master' mappers, the others are learning fast and occupying lower levels. We are seeking another 'master', trust me.

The county map below provides some context for the density of linework...much of it compiled from published sources. However, most of those sources are quite general and particularly weak on the Q geology...which is our focus. Note, a couple of them are strong on Q, which is good news for us.

The second image shows a close-up in the NW corner of the county. The mismatch you see is dominated by our refinement of the bedrock-alluvium contact. Other mismatch related to incomplete (in progress) carving out surficial units. In other words, the polys are based on the original linework...haven't rebuilt the entire set yet.

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Large desiccation polygons, Winnemucca (dry) Lake, Nevada

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A lot of great desert geomorph in this shot I took while flying to the
Owyhee. The cracks are the scene stealer, but the shorelines and fresh
fan-spewage are also cool.

This playa was actually a lake as recently as 1912. It was the right
arm of Pyramid Lake in a sense. Before the urgent national need for
growing stuff in the desert took hold, the Truckee River bifurcated
and filled two basins at its terminus. Ahh, manifest destiny. Once the
river was diverted to grow melons and such, the smaller lake dried up.

State Geologic Maps in kml format and other, did you know?

At the AASG meeting I was reminded of Mrdata...(http://mrdata.usgs.gov/) a very useful but apparently poorly known repository of geologic data, much of which is amenable to viewing on a Virtual Globe or in a GIS program. For example, you can find statewide geologic maps for the entire US on the site. They have been massaged to be uniform in their symbolization. Though derived from small-scale maps, these little babies are pretty useful for visualization when dropped into GE and made slightly transparent.

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I'm curious as to the ratio of geologists who could use this to those who know of it.

Link to National Dataset:

http://tin.er.usgs.gov/geology/state/

Link to Nevada:

http://tin.er.usgs.gov/geology/state/state.php?state=NV