Day 101: November 23, 2007 Fieldwork

  Salta, Argentina
Friday, November 23, 2007

Day 101: November 23, 2007 Fieldwork

I got up at 6:45 and got everything together for the field. The day was already blazingly hot and the locusts were buzzing all around the apartment making a real racket. I considered not wearing a t-shirt under a flannel shirt, my usual field attire, because of the heat. I decided to go with it anyhow; I could always take one shirt off. Elena was feeling much better so that was a worry off of my mind.

Toyo, Claudia, and I left in the white truck at 8:10. We made quick stops for ice and coca and then headed south to Coronel Moldes, Toyo at the wheel. I don't think Claudia had visited the quebrada since she measured it in 1991.

Río Seco Eolian Beds

Anta Formation Strata

We arrived at the end of the road and started walking at 10:10. From the beginning, it was obvious that everything would have been much easier if Claudia had accompanied us the first time. My sample locations in her stratigraphic column were off considerably. She placed them at their correct levels. We walked another half an hour upstream from the point where Toyo and I started the first time. Stratigraphically, it was only about 400 meters lower but the river runs subparallel to strike, winding around many tight bends. We had to cross the stream more than 30 times. As we walked, clouds from the west blew in and hid the sun. The temperature dropped considerably and we felt occasional raindrops. I was glad I had my two shirts on. Claudia complained about being cold.

Toyo and Claudia Drilling a Sample

Toyo Orienting a Sample

The eolian beds of the Río Seco Formation form steep walls in the quebrada, making the it considerably narrower. It would not be a good place to be in a flash flood. We took a pole position sample at the top of the Eocene Lumbrera Formation and then began our magnetostratigraphy sampling. It went quickly; the rocks were ideal for drilling. We will definitely have to return to resample after I run the initial analyses. I'm sure our sample spacing in the Río Seco is too wide. Once we hit the Anta Formation, we shortened our separations. Not far below the place where Toyo and I started sampling two weeks earlier, Claudia spotted a 2 cm-thick tuff, the first one found in this stream.
It even had biotites in it! I collected about a kilo to see if we can get a date out of it. I also took a couple of pictures of Toyo and Claudia doing the sampling to use in future presentations. I've always meant to take pictures like these but never did. I can't think of two better people to use as the "models".

Claudia relocated the remainder of our earlier sites in her stratigraphic column as we walked back to the vehicle. We arrived at 4:00 and made sandwiches for a very late lunch. It started to drizzle about a minute before we arrived at the truck. We ate quickly and then started back toward Salta. I joked to Toyo that now it was time to play "Count the Drunks", referring to all of the drunks we saw on the road on our return to Salta two Fridays earlier. Within 5 minutes, two drunken farm hands came around the corner on a tractor. They were the guys who had given us the peaches two weeks earlier. We exchanged greetings for a couple of minutes and then drove off.

"Uno." I said.

Toyo corrected me, "Dos."

Fortunately, they were the only drunks we recognized on our trip back. We were a couple of hours earlier than the other time and there was a light rain the whole way, both of which were probably deterring factors.

Back at the apartment, I took off my soaked boots and socks. Elena breezed through quickly, dropping off her pack and then going out for dinner and a movie with Carlos and other friends in the city center. She thinks that her camera may have been stolen from her pack at school.

I cooked and ate a choripan and then shared the bottle of San Juan white wine Silvia had given me with Jorge and Bernardo. They went to bed at 11:45. I stayed up until 12:45 waiting for Elena so I could open the gate. In spite of my long day, I didn't fall asleep like I usually do.