Tuesday, May 20, 2014

Mono Basin

IMG_0743We plan our travels around major attractions – National Parks, cities, well know points of interest, and the occasional Escapees rally or RV Park.  From there, we start looking for what else may be available in the area of the major attraction.  Many times we find gems of other attractions that we never had heard of.  For example, between Big Bend and Carlsbad we found Balmorhea Springs.  Around White Sands, we found Three Rivers Petroglyphs, Valley of Fires, and Trinity Site. In the area of Zion, Bryce, and Grand Canyon, we found the Coral Pink Sand Dunes.  All fabulous attractions in their own right, but ones that we just happened upon rather than specifically planned to visit.  Finding and visiting these hidden gems is often as much or more a joy than the well-known ones.  Such is the case here on the east side of Yosemite – we found and explored the Mono Basin including its signature feature, Mono Lake (pronounced “moe-no”).

IMG_0716All the beauty in the pictures from Yosemite was formed by eruptions of granite rock and then cut and carved by the massive glaciers of the last ice age.  As the glaciers advanced and then receded, they also formed this “bowl”, Mono Basin just outside the Park.  Being a bowl, there is no way for the water in Mono Lake to escape other than through evaporation so it is a salty lake with salinity twice the level of ocean water.  There are only two things that live in this salty environment – brine shrimp and alkali files (alkali flies are shown in the picture to the right).  There are 15 trillion brine shrimp in the lake (yes, trillion with a T).  We are not sure who tallies them, but we sure hope they don’t lose the count along the way.  In what appears to be a lifeless environment, life is in fact teeming.

IMG_0734All these simple beings make Mono Lake a major feeding grounds for migratory birds.  There is one species which migrates between northern Canada and southern Argentina and their only feeding ground during this trip is Mono Lake.  But the lake became greatly endangered during the 1940’s.  The City of Los Angeles extended their fresh water aqueduct on up the Owens Valley and they diverted virtually all of the water from five mountain streams that all used to flow to Mono Lake.  The Lake level dropped 45 vertical feet and it lost half its volume.  The Lake was very much in danger of becoming a dry lake bed just as had happened with Owens Lake in the southern end of the valley.  In the late 1970’s local residents formed an association to appeal to Los Angeles to save the lake.  Los Angeles refused to stop any of the water diversions.  After 10 years of legal battles, The California Water Resources Control Board finally ruled that Los Angeles had to provide sufficient water to the Lake to keep it healthy.  The Lake is now back on the rise.  Lee Vining Creek in the picture to the right is running again; previously all the water that is now in this creek would have been diverted off to Los Angeles.

As the lake level lowered over the years it did expose these amazing rock formations called tufa.  The lake is full of carbonates, and the mountain streams that feed the lake carried lots of calcium.  The mountain water flows fed springs that bubbled up calcium from the bottom of the lake and when combined with the carbonate formed calcium carbonate otherwise known as limestone.  All of these formations were hidden from view under the surface of the lake until the lake level fell, but with that fall the tufa then died.  When the lake finally rises back to its mandated level, some of the tufa will be covered again and could come back to life.

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IMG_0919Also in the Mono Lake Basin are the Mono Craters.  It is a small mountain range just south of the lake all formed in the AD era from volcanic eruptions, the last one occurring as recently as 600 years ago.  We hiked up the wall of one of the craters.  Instead of a giant hole like we had seen at the steam crater in Death Valley, this crater was filled with a “plug”.  The earth’s magma had not just steamed the ground water and blown out a hole, it had thrusted up through the hole and created a dome of rock, cinders, obsidian (rock turned to glass), and other materials.  And before any one thinks Gary has turned into He-Man, I will quickly point out that boulder he is hoisting is made of cinders.

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