Sunday, March 24, 2013

Death, Life, Rocks and Valleys

Today we visited Death Valley!

It was my first time there, and definitely the more interesting for having geologists along to tell stories about the rocks nearby. Dwight, Sam, LeAnn, Erin and Annie were surrounded at each of our stops by people curious to hear more about the valley.

In terms of statistics, the Valley describes itself in terms of superlatives: hottest, driest, lowest.

  • It was here that the hottest temperature on record was recorded: 134 F (56.7 C).
  • A desert is defined by having a higher rate of evaporation than precipitation. Death Valley has an annual precipitation rate of 2.36 in (60 mm) and an annual evaporation rate of 128 in (3.25 m).
  • The Valley floor, located in a basin between two ridges (part of the basin-ridge system common throughout Nevada) is 282 ft (86 m) below sea level - the lowest point in North America.
However, I was surprised to find, the valley also has a nearby peak of 11,000 ft, as well as supporting way more life than its name implies. Everything from bristlecone pines to kit foxes lives in or around the valley, perfectly adapted to survive in the climate that drains humans dry (heh).

We visited, in order, Zabriskie Point, Ubehebe crater, Mosaic Canyon, Father Crowley's Overlook, and Fossil Falls. We also passed Owen's Lake, sadly dried up due to water diversion to LA.

Zabriskie Point looked like this: 
Not pictured, an alluvial fan was located behind the rocks, where runoff during the Valley's flashfloods (it doesn't rain often but when it rains it pours) would roar out to base level - the lowest point in the Valley.

Here's the Ubehebe crater (NOT shown to scale):

We walked around the perimeter and I ran down to the bottom with Annie and Erin, our TA's from the fall. Sadly, I am unfit and the walk up was not nearly as much fun. 

Bottom from top:

 Top from bottom (if you look really closely, the tiny dots around the rim are people walking):

Here's another picture to try and give you a sense of scale. I think the West is just too big to fit in my camera (which is awesome).

Next was Mosaic Canyon, or the photogenic canyon.

The walls are actually calcium carbonate (CaCO3) folded on themselves due to heat and pressure softening them, and faults folding them. But water draining from higher up, cut a path through the rocks, polishing it and making it easy to inspect the layers. Several crowded round Dwight, Sam, LeAnn, Annie and Erin for story time.

Here's Erin explaining how folding works. She'll probably kill me for posting this :).

After a quick water break we drove up a long winding spectacularly beautiful highway. Unfortunately I slept through it all, so I no pictures to show you. But I woke up in time to see the view of Panamint Valley once we reached the top, which was spectacular. Here's Emily at Father Crowley's Overlook :)

Finally we started leaving the valley regions. We finished our leaving about an hour later (Death Valley is the US's largest national park, and longs to keep you there - til you die) but on the way out passed by two more things. Owen's Lake was a big basin filled with a puddle about 1 foot deep and some yellow grass. 10,000 ago, it was a beautiful lake, and even as soon as 50 years ago, paddle boats transported silver ore from the east to west side, while orchards with cherries, apples, pears and the like grew on the banks. However, LA diverted the water from the stream feeding the lake, and left it with only enough to prevent the basin from drying out and blowing dust everywhere. (On the other hand, perhaps due to draining of the basin, the land was saved from development by outsiders.) One cool thing about the diverted water - LA managed to set up a system such that the water traveled due to gravity and had no need to be pumped over the mountains. I'm hoping someone back at MIT can build me something like this.

Last but not least we saw Fossil Falls. There were no fossils (misleadingly) but there was plenty of cool rocks to admire, polished as there were by waterfalls originating from water in Owen's Valley. The water was no longer there, but the rocks remained for us to pretend burrow in, through and around (see, Holly in a hole!).

Now we're at another awesome hotel in Ridgecrest (the rooms here are so big there are ECHOES) and we're looking to have another awesome day tomorrow!

Til then, big beautiful west.


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