Fire Cloud...
An irregular marking on the exterior of Native American pottery: usually resulting from burning fuel coming in direct contact with the vessel during firing

Monday, 5 May 2008

San Juan River Raft Trip

Bluff, Utah to Mexican Hat, Utah

At 4:32 AM this morning the International Space Station became visible in Bluff, Utah. It wasn't as bright as I expected it would be. You would think anything with a $190 million dollar toilet would be dazzling.

The raft trip departs near Bluff at 8 am and ends up in Mexican Hat, 26 miles downstream, around 5 pm. Our guide, for some reason, wears a striped necktie with his straw hat and tennis shoes.

The first stop is a sandstone wall with 150 yards of petroglyphs. The earliest of these may date back 10,000 years to Clovis Man. More elaborate designs are about 1,000 years old by the basketweaver culture. I suspect that the ones that say "BLM Sucks" are fairly recent additions. One recurring enigmatic design appears to be Kenny from South Park.



We see more Indian ruins, after a 1/2 mile hike, a little later in the morning. These were the Anasazi, ancestors to the local Zuni, Hopi and Ute tribes. The cliff shelter forms a natural amphitheatre. I can clearly hear the group conversations from 100 yards away. You can imagine voices from the inhabitants on a warm summer day.



We run into some mountain goats about halfway though the float.



It's interesting to watch the layers of sandstone along the river. One yellow layer traps petroleum. Sometimes it dives into the earth, sometimes it reappears...Mrs. Phred claims she can smell oil. The red layer is Navajo sandstone, petrified ancient sand dunes. There is one very old layer called Paradox. It is believed to have originated near the equator, in a shallow sea, back before the continents drifted apart.

The thing about the yellow layer of rock is that it's fairly impermeable. If you can find a place where it folds up into an anticline, the low density oil and gas bubbles up and accumulates at the top of the dome or fold. It's the kind of structure that gets oil geologists really hot.



I like this picture of a desert bee chowing down on a prickly pear flower.





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