 We left Santa Monica at around 8:30 and made it to the Salton Sea a few hours later.
While headed to our campsite, we paused to look at the saline waters that fill this trough
and discussed the geology of the area.
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 We then entered Painted Canyon, looking for a nice place for the night.
While reconnoiting for that perfect camping spot (well, at SMC we all want to be happy campers)
the most adventurous member of the group got stuck in sand.
Getting back on track, as you can see, was no problem at all.
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 Eventually we found a large opening, and we spread our tents at the foot of steeply-tilted sandstone layers.
Some of us were too tired and decided to sleep in the car.
Others set up lavish accomodations where everybody was invited for tea and cookies.
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 On that first day, we took a hike through a slot canyon.
The mouth of the canyon is actually hidden behind a landslide
but after 20-30 minutes of ups and downs the path opens up and the surface becomes flat.
Here, Jack and Judy stroll along the sandy floor of the canyon.
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 Those 20-30 minutes of ups and downs were actually part of the fun:
at times, the walls of the canyon were getting so close that only one of us could go through
and in a few points we had to climb on ladders
that the Bureau of Land Management graciously put there for explorers like us.
We really experienced the motto that says that "the journey is the destination".
In this image, Tom is helping with some of the backpacks.
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 The vision of the Salton Sea at sunset accompanied us to our campsite
where we started a fire, cooked our meal and chatted under the moonlight.
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 The following morning, after a hearty campsite-made breakfast,
we headed south on California 111 and then California 86S, towards the Brawley - El Centro area.
The air was clear and different geological adventures were waiting for us.
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 At first, we stopped at the Algodones Sand Dunes, now part of a state park actually called Imperial Sand Dunes.
Wind was strong as usual in this desert strip, so we were able to actually observe sand in motion:
this red-colored sand moves by saltation on the back of the dune and then falls at its front because of gravity.
We saw how the ripples are forming (lower left) and the advancement of the dune crest.
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 Of course there are several methods to do science while in the field:
this image shows how Mehdi decided to experiment how does it feel to be a grain of sand.
He did not report any rounding or sorting.
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 The next destination was on the banks of the Salton Sea,
where we stopped for lunch after a long drive form the sand dunes.
This is where a series of volcanic extrusions created a big black mound that goes by the name of Obsidian Hill.
We had lunch here, lulled by the noise of the breaking waves.
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 A couple of mile north, still on the banks of the Salton Sea, is Red Hill:
an altered mound of rhyolite, a silicic extrusive igneous rock, standing high on the water.
Rapid oscillations of the water level might leave wide muddy areas exposed, as is evident in this image.
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 Further north is a field of mud volcanoes.
Gases rising to the surface, mostly carbon dioxide, cause liquefaction of muddy sediments;
liquified mud is then ejected at the surface, creating a little cone around the vent.
While there is a link to plate tectonic activity, these are not real volcanoes!
In this image you can see the mud (and its shadow!) rising through the vent
and also the trace of the impact of the individual pulses on the "crater" of the volcano.
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 Water can collect in pools that fill depressions that form around the volcanoes.
This water contains a lot of salt and tends to evaporate, favoring the deposition of minerals.
Some of these waters are at high temperatures and host a variety of bacteria that thrive in these conditions.
In this image Hammam and Marlon collect water from the brine pool.
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 Sometimes gas is released from underneath a pool, or a crater gets filled with water.
The result is a pool of bubbling muddy water, like in this image.
Notice the pattern of mud cracks all around this little vent.
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 All this hot water bubbling upward, could it be used for any purpose?
Of course it can: on the banks of the Salton Sea are a series of wells used to tap the water.
Here is a geothermal well whose waters are used to generate electrical energy.
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 Back to sedimentary rocks: this is a dry waterfall that tells us two different stories.
The first refers to the present, and is told by the vertical ridges in this image:
when water drips along the wall, it easily erodes sand and finer sediments;
but when the water encounters bigger grains, such as gravel, it will just go around them,
creating an "erosion shadow" that will result in a ridge of non-eroded sediment.
The second story can be read in the horizontal lineaments:
you can see cross-bedded lamination (lower part)
and a series of gravel lenses (middle and upper parts)
that tell us that this sandstone was originally deposited following a very swift river current.
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 Let's not forget that we are very, very close to the San Andreas Fault!
Deformation along this plate boundary might result in local compression or extension in the surrounding rocks.
In this image, tectonic compression has cause some of the sedimentary layers to bend, or fold,
in structures called anticlines (like the fold to the left, pointing upward),
and synclines (like the bent layers to the right, pointing downward).
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 The San Andreas Fault itself shows its presence here
by causing an alignment of very distinct rocks at the mouth of Painted Canyon
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 At the 1000 Palms Oasis, a trail takes visitors along the San Andreas Fault.
At this location the fault causes underground water to upwell to the surface.
As a consequence, a very thick palm oasis developed along the fault.
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 The shadow of the palms was what we needed after a day in the heat.
Notice how big these palms are and how dense is this oasis.
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 This view of the path that leaves the oasis and enters the desert once again
ended our weekend-long field trip in the Salton Sea Trough
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