North Muddy Mts: about those provisional maps...

North Muddy Mts, NV: about those provisional maps...

pics by Harlan W.S.
April 09, 2011

This was a quick substitute trip. We started N of Buffington Pockets, and intend to loop over several small peaks. Alas, our plans were cut short by a front of lightning storms rolling into our path. But besides providing an enjoyable climb, the trip provided some edification on maps and accuracy.

Years back, the USGS decided to issue "provisional maps" which had not had the full vetting of traditional topos; there are many assurances that such maps should be used with just as much confidence as fully vetted maps. But in NV, provisional maps have proven to have fairly abundant mistakes, particularly in the selection of highpoint on a ridge with many lumps (e.g. Pahrump Point, as described here). There are obvious guffaws-- like marking every gully with a perennial stream, even in the driest, most desolate areas. The topo maps for this area are provisional, and provided yet another exanple of error. Let the story unfold...

Here's the basic topo map; it looks like we stopped short of the highpoint! Well, I had this position confirmed with two GPS units reading to +/- 10'. The purported conical highpoint did not exist....	...and here's why the USGS was wrong. This is the composite aerial photo as used for photogrammetry; the east side of the peak is bound by cliffs with deep shadows, a notorious bane for photogrammetry.	OK, back to the trip. We walked up the road toward HIdden Valley for quite a while, then kept going SE toward the peaks. The clouds were washing over the ridge, which was quite cool-looking.
		View back NW.
	DB handles some unnecessary roughness.	View S to Muddy Peak.
Sage.		We went up a cool canyon.

View to N along ridge; we intended to go there next, but were chased off by storms.
	view N.	The map puts a conical hill behind CP, another 20 meters or so higher. That highpoint doesn't exist.
View S to the higher Muddy Mts.
Again, the next intended goal to N. When we got to the saddle, we saw a storm front with thick clouds and lightning a few miles off, so we descended...		Neat limestone hoodoos...
	Oops, we hit a 30' dryfall, so we took a bypass...
		Beavertail.
Desert marigolds.