After leaving Lake Tahoe, I headed east down the Sierras on US-50, intending to drive across Nevada in one afternoon. I ended up spending three days there.

The stretch of US-50 through Nevada is called “The Loneliest Road in America” because there are only 5 towns along the route and almost nothing in between. Actually, it wasn’t very lonely at all, because there were plenty of other cars traveling in both directions. However, there were a few times where I could no see no cars either ahead of me or behind me. And you can usually see quite far on this road.

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The state tourism board (or whatever it’s called) has even come up with this little “passport” book that you can get stamped at all five towns and send in to get an “I Survived the Loneliest Road” certificate. I got my book stamped, so we’ll see when I get the certificate.

I saw more different kinds of “___ Crossing” signs during my transit across Nevada than I have ever seen: Bear (in Lake Tahoe), Deer, Horse, Cow, Antelope(?), Fire Truck, and Tractor.

One thing about this road is that if you’re at all unclear about what the term “Basin and Range” means, US-50 will straighten you right out.

That’s all you see driving across Nevada: Basins (valleys) and Ranges (mountains). You can see that very easily on a topo map.

All of these small, north-south oriented mountain ranges separated by valleys. Well, those mountain ranges weren’t always so small. The Basin and Range province is being created by extension of the crust, because the movement of the Pacific plate along the San Andreas Fault is creating tension on the crust.

What happens when you start pulling crust apart? It breaks into faults. These faults run north-south roughly parallel with the orientation of the San Andreas. These are normal faults, where the two blocks separate, thus making the crust longer and thinner. But underneath these roughly vertical normal faults are horizontal detachment faults. So the blocks don’t just separate in a linear fashion, they slide down and rotate.

The result of this is that one edge of the rotated block is left sticking up, forming a mountain range. The other block has dropped down along that axis, and forms the valley. Incidentally, the technical terms for the mountain and valley are “horst” and “graben”. I just love those words. Especially graben. Graben. Say it a couple times and I know it’ll grow on you too.

So the mountains and valleys formed and then the mountains immediately started undergoing erosion. And they’ve been doing this for millions and millions of years. In some places, the sediment filling the valleys is tens of thousands of feet thick.

Whenever you get this crustal extension, volcanic activity is not far behind. Although it’s not right out in your face, the volcanism can be seen if you know where to look. And one of those places is the very first interesting spot along the road.

Just past Fallon (town #2 for the passport book) is Grimes Point. This is a field strewn with basalt boulders covered with petroglyphs.

These petroglyphs were created by scraping away a layer of desert varnish covering these basalt boulders.

Desert varnish is created by oxidation of manganese by bacteria.

The symbols are thought to have had mystical power in helping with game hunting.

You might wonder “What game? Aren’t you in the middle of the desert?”. This area is now a desert, but it was once a lakeside location. Around 12,000 years ago, a large portion of Nevada was covered by Lake Lahontan, which was up to 700 feet deep.

In the distant hills, you can barely make out the wave cut platforms, showing the various water levels of the lakes. Now when the Native Americans who made these petroglyphs lived in the area, the water level was much below its maximum, but the water was still there. And where there’s water, there’s game.

These petroglyphs are as much as 7000 years old. Very nearby Grimes Point is Naval Air Station Fallon. This is the home of the TOPGUN Naval Fighter Weapons School. Which means that while you’re walking the trail around these ancient inscriptions, you’re hearing and seeing (mostly hearing) these flying overhead:

It took a couple tries before I actually got a shot of these. I kept looking in the direction the sound was coming from, but then I figured out that they are nowhere the sound by the time you hear it. I have no idea what they are.

The next interesting point is just a little further down the road. And Sand Mountain really is quite striking. Even though it’s a desert, there’s really not much sand along this road. In fact, most of the bare ground is covered with desert pavement. Desert pavement forms when wind blows away all the small particles, leaving only densely packed stones at the surface.

But here is a mountain of sand! (You can see some desert pavement to the left of the road in this picture.) Remember that old Lake Lahontan? Well it was here, too. And it left a lot of sand in this area, which got blown around. As it turns out, Sand Mountain sits at point where the winds hit a mountain range, lose their energy, and deposit all their sand.

Right next to Sand Mountain, you can see very clearly some of the wave cut platforms from Lake Lahontan.

The next stop on the tour was Fairview Peak. This is a fault trace exposed by a magnitude 7.1 earthquake on December 16, 1954.

You can see how much displacement there was here, but there’s even more displacement further up the road.

Fairview Peak sits at the eastern edge of one of the “Ranges”, and this picture is looking south. So the ground to the left (east) moved down and that to the right (west) moved up. This stretched the crust a little bit more, so the creation of the Basin and Range province is still continuing!

One last stop before ending my first day in Nevada: Stokes Castle

This was built by Anson Stokes in 1897 to be a summer home for his family. He was the owner of a railroad that ran between the nearby town of Austin and Battle Mountain. After building the “castle”, the family lived there for a month and then abandoned it.

So after my first day of driving through Nevada, I’d barely made it halfway across the state, but I arrived in Austin, town #3 for the passport. The population of Austin is about 300, but they have 4 motels and 2 gas stations, not to mention a few restaurants and stores. Obviously I’m not the only person who feels like they need to stop for the night in Austin.

After spending the night in Austin, and eating breakfast in a former hotel that was moved, piece by piece, from Virginia City, 165 miles away, in 1863, I continued my sojourn east.

The next interesting stop was Hickison Petroglyph Recreation Area. It contains, guess what…petroglyphs!

But before we talk about the petroglyphs, let’s just get this out of the way: There’s a trail to/around the petroglyphs. There are two parking areas, one is right next to the petroglyphs, one is a half mile away, with a trail connecting it.

Not only did I park in the “wrong” parking area, which was totally not my fault because the signs pointing to the two parking areas are labeled “Trailhead” and “Campground” so of course I took the “Trailhead” turn…but once there, I got on the wrong trail. I’ll bear some responsibility for that. It was just carelessness and sloppy map reading. And I’ll also take responsibility for the fact that it took me almost an hour to realize I wasn’t on the alleged half mile trail.

But I got some cool pictures! So these petroglyphs, rather than being carved onto basalt boulders like at Grimes Point, are carved into ash-flow tuff. These rocks are the solidified remnants of a pyroclastic flow. So this is a very different kind of volcanism than that which produced the canvas for the Grimes Point petroglyphs. If you don’t know what a pyroclastic flow is, watch this video:

Commonly found with this kind of tuff are breccias. And this is where my misadventure on the wrong trail becomes a good thing!

I’m not sure what made that cavity, but it’s a window through which you can see all the many bits and pieces that were flung out of the volcano along with all the pyroclastic materials.

Here’s another. Really, these were all over the place. But let’s get back to the petroglyphs.

Isn’t the way this stuff erodes just so cool?

This is a view of Lone Mountain, which is just west of town #4, Eureka. I know this isn’t the best photo, taken through my car window with my cell phone. But I think you can see that there are tilted layers, right?

The oldest layer, at the far left, is Pogonip Limestone. This layer was deposited from the late Cambrian through the middle Ordovician periods, or roughly 550 to 450 million years ago. At this time, most of the North American continent was covered by water, which would be expected because limestone is almost always deposited in marine environments.

The next layer up, a fairly thin but relatively bright white layer, is Eureka Quartzite. This layer of metamorphosed sand was deposited in the middle Ordovician period, around 450 million years ago. It appears that the sand was blown south from Canada.

The next two layers, which are a little difficult to distinguish in my photo, are the Hanson Creek Formation, laid down in the late Ordovician, about 444 million years ago, and the Roberts Mountains Formation, from the early Silurian, around 430 million years ago. A very thin layer of dark chert separates the two strata. These are both limestone layers, indicating a return to a marine environment.

The next, light layer, is the Lone Mountain Formation, a late Silurian (around 416 million years ago) dolomite layer. Next, forming the peak of the mountain, is a dark layer, the early to middle Devonian Nevada Formation dolomite. So we’re still underwater.

Not much further along the road is Devils Gate. Here we get a close up view of the Nevada Formation, which formed the peak of Lone Mountain just about 10 miles back.

I don’t have much to say about town #4, Eureka, or #5, Ely. I pretty much stopped just long enough to get my passport book stamped and moved on.

I took this picture because the color contrast of this mountain was striking. I can’t find a name for this mountain, but it turns out to be the site of Rose Cave. (If you click and zoom in, you can see the cave entrance behind the utility pole in the foreground.) This cave is a migratory stop over for Mexican free-tailed bats. But guano is useful for production of industrial chemicals, so they started mining it here in the 1920s. To expedite the mining, they dug a tunnel below the natural cave entrance in 1926. Unsurprisingly, this messed up the bats, so in 1998 the tunnel was closed off. There is now concern that new wind power turbines in the area might kill the bats.

Ok last stop in Nevada was….Great Basin National Park. I was only there not even 24 hours, but I think I had the absolutely most awesome campsite ever. EVER!

Allow me to give you a tour:

From my parking space, I had to cross a footbridge over creek #1.

Then a short walk to the table/tent area.

From which you discover that creek #1 is actually composed of creeks 1A and 1B.

And on the other side, creek #2, which is actually creeks 2A and 2B.

So to give you an idea of what I got to listen to all night:

I no longer need any of those white noise CDs, because I made my own.

Notice how green and lush everything is. Surprising, no? I mean it’s right in the middle of the desert.

The highest mountain in Great Basin is Wheeler Peak.

It’s the one on the right with the nearly vertical face.

From this view, you can very nicely see the cirque and the rock glacier. As you can see, the weather was starting to get ugly, and the road up to this point was scary enough when perfectly dry. I didn’t want to be descending it in a downpour. Fortunately, the other big attraction in Great Basin is totally weather-independent.

This is Lehman Caves. And man is it hard to take pictures in here without a tripod. And they don’t allow you to bring tripods on the guided tour. So, these are the best I could do.

And that concludes my surprising tour of Nevada.