28 April 2009

update: the demise of deposit 10a, the flattening of deposit 1

top of deposit 1, as of 29 apr 09

After about 8 months of digging, Deposit 1 is finally starting to look markedly different than it did when we first unveiled it -- well, to us, at least. Yes, it's still a dusty hunk of rock, but now it's a dusty hunk of rock that's around half a meter shorter than when we first got it.

As I've hopefully mentioned before, we work in 1m x 1m grids, and dig down 25 cm at a time. You've seen this before:

Main fossil deposit as of 7 Apr 09

...the large, convoluted bone mass that was keeping us from "closing" grids B-1 and B-2 and moving on to other portions of the box. In both grids, we're working on level 3, which is the section of dirt 50-75 cm below the original ground level of the deposit. Does that make sense? Those large saber-toothed cat scapulae and innominates were sticking out above floor (the bottom of each 25 cm deep level) and needed to be removed before moving on.

Now the grids look like this:

main bone deposit

Yes, there are still bones, but if you look carefully, you'll note a wonderful lack of scapulae...

tara and shoulderblade

...because Tara got the last one out! Everything left in place is too far below floor to excavate at this time. The grids surrounding the bone mass are still at level 2, so we have to get those down to level 3 before we can open up grids b-1 and b-2 at level 4. Did that all make sense? Excavational peccadilloes are difficult to describe via the interwebs. To sum up: if we keep excavating just the main bone deposit, we'll wind up with a giant hole in the ground (in the box) which will be too deep to keep digging at. So: sterile grids for us, for a while.

In non deposit 1 news: as Ryan and I have both mentioned, 10A is no more! We time lapsed it's final moments:

I have to say, I like the soundtrack to this one better than last week's, but I don't think anything will match excavation to the tune of "I Am the Walrus." Ah well.

Next week: we just laid grid lines out for 5 new deposits -- 7A-E! We're very excited to start work in new, softer dirt. Pictures soon to follow. OH! And click through to flickr to check out the giant freaky black (and brown) widows Laura and Michelle found under 10A.


Anonymous said...

hey! congrats Tara on that last scalpulae (is that right?)! a bit of cheer-up: dont become a gloomy-gus about working on "fresh" dirt, maybe you'll find a...well, something you havent found yet! or maybe another small mamilian jaw bone...completely intact!

well, good luck with 7A-E!


Spencer said...

Wow, it really does look different...I hadn't realized....