FROM THE MOUNTAINS

We all got up bright and early and even managed to get out of the hotel at a reasonable hour. The first day of a project is always the hardest. There are a lot of little details that rear their ugly heads on the first day, but this group from UNR had done quite a bit of field work and they had everything pretty well under control.

Our first stop was Santa Fe Dam where we waited for people from the County of Los Angeles to let us through some gates.

Below is Stefan Beck who was one of the field crew. The dam had a nice swimming area behind it that we got back to the following day, but the dam itself sure seemed a bit larger than it needed to be. Maybe it's just because it was the dry season. All of the park facilities in the picture below are behind the huge, and long, dam in the picture above. Hmmm.

Once the people from the county showed up we made our way up the San Gabriel River and to the edge of the Angeles National Forest. This was our starting point. It was all downhill, literally, from here.

You could almost smell the ocean air...or maybe it was just the heat getting to me. The temperatures were well into the 30's Celsius (90's Fahrenheit). And the refreshing, cool water of the river was no help as can be seen in the picture after the one below of the river bed.

Behind us were the San Gabriel Mountains. That structure crossing the road was a conveyer belt that ran all the way from the mine where the side of the mountain is scarred, over to some processing and loading equipment.

I'm not sure what they were mining, but that was the longest conveyer belt I've ever seen. Below was the end of it, which was no where near the part that crossed the road in the picture above.

And so our fun began. There were four teams of three people each. That meant that each team had 30 Texans to deploy. The Texans were spaced out (the "spacing"was) along a line with 20 meters between each Texan. That meant that a line of 120 Texans would cover 2.4 kilometers. Each team was responsible for 600 meters of the line.

In the days before the project started, and even up until the last day, a team went out and surveyed ahead and determined where each team would start their 600 meter long line. They left small flags at each point, took GPS measurements, and produced a list of instructions of what to look for in the area to find each flag. Once each team found the beginning of their segment of the line they would start laying out Texans every 20 meters using the wheel to measure the distance.

The way out team did it was one person would start up the line with the wheel dropping off a flag each 20 meters. The second person would drive the vehicle down the line, stopping every 40 meters or so, and drop off the Texans at each of the flags. If the planting was easy, that is the if the ground wasn't too hard, the driver could help by planting a geophone here and there along the way. The third person would work their way up the line just planting geophones. When the first person doing the measuring was finished he would work his way back from the end planting geophones. It worked pretty well. It took about 20-25 minutes to get all 30 Texans deployed.

The conditions of the ground over the whole line varied from concrete to beach sand. The ground along the bike trail was, for the most part, packed gravel, so sometimes it needed a little persuading to allow the spike on the geophone to be planted. Wes Thelen from UNR is using a cold chisels and a small sledge hammer below.

When everything went well, which it usually did, you ended up planting your last geophone 20 meters from the flag at the beginning of the next team's line segment.

Once all of the Texans were deployed the time was recorded and the was clock started. With lines of this length, 600 meters, we left the Texans out for 30 minutes. They were programmed to record for 2 minutes, then go off for 30 seconds, and repeat for 11 hours starting at 7:00 in the morning. As part of the permit we had to be off of the bike path by 6:00 in the evening.

During the 30 minutes that the Texans were deployed there wasn't much to do but wait. In some cases we drove up and down the line a bit to make some noise to record.



DIRECT LINKS TO PAGES:
URBAN SEISMOLOGY IN THE NAUGHTIES
WARMING UP
FROM THE MOUNTAINS
TO THE PRAIRIES
TO THE OCEANS, WHITE WITH FOAM
MISSED FINISHING BY THAT MUCH
SIN CITY, BABY!!
THE ELECTRICITY BILL FROM HELL
NEXT!
DAM THE CASINOS...FULL SPEED AHEAD!
THE ROAD HOME

2014-08-03