[AP wire story] Freeman Dyson, a physicist who has written about religion’s role in modern culture, won the $940,000 Templeton Prize for Progress in Religion, one of the richest awards for achievement in any field. “Science and religion are two windows that people look through, trying to understand the big universe outside, trying to understand why we are here. … Both views are one-sided; neither is complete. Both leave out essential features of the real world. And both are worthy of respect.”
[Burnt Rock Mound (after work)] Today was the day. The day when we finally dig down through the spring throat to find out if there are answers to some of our questions there. Its been one of the best single days doing archaeology I’ve ever had.
At first, we were standing back from the throat all the way on top looking down. We had been anxious to see what happened to the dark clay layer as we came in towards what we hoped was the spring throat. Backhoe Bob is good, real good with the hoe. He was taking things down nice and even, so even though we couldn’t really see the floor but he was laying the bucket loads out in such a way you could follow the stratigraphy in the backdirt. We got past the modern digging into the throat about 3 meters down, so the trash and debris dropped off sharply and we were just looking at good clean soil. About two scrapes past the end of the digging a buff colored sand came out of the bucket. We hadn’t observed that color of sand yet in any of the pits or previous trenches so we knew we were getting close to the stuff we came for. We were still getting a substantial amount of the green clay which was also good. Our model was that the spring throat would be filled with clean white sand with buff colored sand surrounding the white. Around the sands would be the dark brown clay which would be jacketed by the green clays, the farthest away from the water flow. In my mind, it looked reminiscent of that volcano in Jr. High science with the water replacing the central lava tube and the sands and clays representing the magma flows.
What we knew we had was a concave structure of some sort that appeared to either be intrusive into the caliche/calcrete (I’m still not sure what the difference is, but the geologists have talked about it a lot) or the caliche had formed around it. These two interpretations lead to very divergent scenarios for the spring mound. If the clay is intrusive, the mound and everything associated with it is likely mid-Holocene [< 5,000 years before present (B.P.)], but if the caliche has formed around the clay structure, then its older, perhaps much older, but likely at least 9,000 years. Older. I want it to be OLDER!
So, that little diversion was to come to this point in the backhoe work at the mound where the buff sands come out of the bucket. There is a phenomenon associated with springs called a ‘black mat’ that is somewhat of a holy grail for springs research. Well, not a holy grail ’cause people do find black mats but you get the idea. The very next bucket has the blackest stuff I’ve ever seen in it (OK, coal is blacker and I have seen coal). Oooohhh, black mat. I immediately think of the Fremen in Dune (Frank Herbert) chanting ‘blaaack maaaat’ during the Little Maker ceremony. (No, I don’t know where these things come from. All I can say is that its interesting inside this head sometimes. I just go with the ride. Mostly.) We had hoped that the clay would be rich enough in organics to be black mats near the spring vent (another name for the throat) but we hadn’t observed any yet. Black mats are desirable because they are loaded with carbon which is dateable and dates in absolute years (OK, radiocarbon years) are very useful. We need a whole host of dates to see how old these layers are to answer the intrusive or in place question. So there is this flurry of sample bags as we begin to grab as much of the black mat as we can find. The next bucket brings more black mat. We’re going to get our dates! This is so cool. The clay layers have been descending as we trended toward the spring vent but we didn’t know for sure if there would be the sharp descent we hoped for at the throat.
We ask Bob to pause so we can get a depth below surface for the layer of black mat. We can’t get in the trench because its too deep to be in without shoring. Shoring takes time so set up and properly done shoring will hide the layers we wish to see. So, we peer in from the surface and drop a tape. We need a profile map and this is the best we can do. Actually, I’m making it sound like its an inferior method but its not. We can see the layers and we can place them in three-dimensional space so the profile will be fine. The angle of the strata are rapidly getting steeper with the black mat outside the buff sands, just like it should be (ideally). The next bucket has some of the whitest fine-grained sand I’ve ever seen in it. Spring sand, just like in the text books. More mapping, Greg is like a profiling machine. When someone has that much focus the only thing you can do is try to be of assistance while staying out of their way. I can do that fortunately, so I try to get into that mode.
As we get deeper into the spring it becomes apparent that the clay has formed a narrower opening that has restricted the spring throat. The spring sand expands below the clay layer like a cave. Again, we talk about which came first, the clay or the spring. Its all conjecture until we can get some carbon dates. So while Bob goes farther into the spring, the questions play in the back of my mind. Multiple springs? That could explain the deep structure away from the throat in the caliche. But a single spring could do that too. Vary the output and hydrostatic head and you could put a clay layer in there that begins to restrict the spring throat. Back and forth, I’m trying to frame the arguments and trying to poke holes in them. It all comes down to ‘how old’. Over and over it hinges on that. Meanwhile more and more spring contents are being neatly laid out and we’re filing sample bags with white sand (it feels like talc), buff sand, green clay, dark brown clay, black clay - the black mat. More tape measurements, lots of coordinates, lots of erasing, more drawing. Data, must get as much data as possible because we can’t come back and check things later. It looks like the throat could be descending to the southeast. Maybe it does, but that could just be the enlargement of the spring sands below the clay, Right now, the only way to find out would be for Bob to dig back under himself, a very bad idea.
Near the farthest extent of the reach of the backhoe Bob has a treat for Greg. He bring up a bucket full of spring sediments and begins to shake it out gradually like he has been doing. Then he stops, rolls the bucket back, raises the arm and swings it around to where Greg is standing and half opens the bucket. There is a rock in the white sand. (Like I said, Bob is real good.) Greg takes several steps forward and picks the rock out of the bucket and Bob pivots the bucket back over and finishes dumping it. The rock is a metate (grinding stone) from six meters below the ground surface. It looks like it broke while someone was finishing the surface preparation. Metate manufacture is a very time consuming process and its easy to imagine how it might have ended up in the spring when it broke. The edges are all rounded off from water action and it has a coating from being in the spring for a long, long time. Its all reddened from the iron in the sandstone oxidizing in the water. A metate six meters down is not what we expected.
So what we ended up with is a symmetrical basin in the caliche, lined with clay and filled with sand. Most of it is a shallow basin, except in the center where it descends sharply around the white sands of the spring. At the bottom it showed no sighs of ending, but we had run out of backhoe. What could be farther down you ask? I hope for Mammoth bone, or more likely teeth, maybe camel bone. Who knows what, thats why we’re looking after all.
Tomorrow, we’ll take out the side of the mound and go through the vent space to confirm the shape of the formation and see if we can find the sandy ‘pool sands’ we found in trench 2 to the north. Then it gets filled in. Kaput. We’re done with the field work on Tuesday and the fence comes down on Wednesday. In a couple of months there will be houses there. That’s life in the city. Thankfully, the landowner graciously let Greg do this.
Then we’ll analyze the artifacts and stratigraphy, and start to piece things together so it sounds coherent. And we’ll check the mail for the results of those carbon dates. I think it’ll feel like Christmas when they get here. The only question then is, will the present be socks or something really wonderful. 
Man, I love archaeology.
[Burnt Rock Mound (before work)] We’re coming up with possible explanations for the massive amount of fire-cracked rock and the shape, positioning, and formation history of the ‘black mat’. Plus, in the midst of trying to finish the test excavations we’ll be giving tours to the Las Vegas Springs Preserve Foundation members so they can better tell the story of our spring mound at the Preserve. Cool! Things are sooo busy right now, but it doesn’t feel like riding a tiger that could eat you at any time, more like a fast horse. A really fast horse without a saddle or bridle. Pay attention! Yes, doing science is exhilerating.
[Royal Astronomical Society] Astronomers Discover Free-Floating Planets in the Orion Nebula. This bring the total number of planets discovered outside the solar system to 40, making their presense in the Universe appear to be common.
[Scripting News] There is a network service story concerning getting editthispage.com and weblogs.com back on the air that is one of exceptional service rather than the all too typical horror story. Plus, yet another reason why Frontier is a better choice for web serving and services than the offerings of the Redmond giant.
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