For training purposes, to make sure all of the equipment worked after being shipped, and to waste a large amount of time, we unpacked all of the equipment and set it up in one of the open courtyards of the geosciences building. The idea was to set up all of the equipment, let it run overnight, and then check the data in the morning.
The sensors for this experiment were Mark Products L-28 three-channel geophones. They are pretty simple units that measure vibrations in the up-down, north-south, and east-west directions. They are pretty simple to install too. They are usually installed in a shallow hole by just aligning them to north and making sure they are level with a built-in bubble level. Juan Pablo Duran and Marisol Gomez are doing all of this, except for the hole part.
The experiment was going to cover a rather long line along a highway, through the mountains, and in a short amount of time. We were looking for a way to set up and transport stations to minimize the amount of time it would take someone to move a station. One station was made up of a recorder, a battery, a sensor, and the timing/GPS receiver. The stations were going to be moved several times during the experiment. We took the foam out of one of the "R"Boxes (the serial numbers start with the letter "R"), and it looked like the solution was found for some of the stations. The amount of time the stations would be deployed was to be hours, not days, so an elaborate, buried vault of some kind was not necessary.
Sensor, GPS antenna, power, clear old recording parameters and data, send parameters, start acquisition. Sensor, GPS antenna, power, clear old recording parameters and data, send parameters, start acquisition. Sensor, GPS antenna, power, clear old recording parameters and data, send parameters, start acquisition. Everything was connected, programmed, and started. Then the trouble began.
No one was usually out in this area at night, so as it got darker we had to replace a couple of light bulbs so we could keep working. I accidentally scared the heck out of Juan when I took this picture...with the camera flash...just as he reached for the bulb. Monica Tabima, the department secretary, thought it was funny. Juan did too after his heart stopped pounding.
The fun and games continued into the night. The problem was that while the area WAS pretty open it was not open enough. There were too many trees and buildings around. We tried and tried to get the GPS clocks to lock to their satellite signals by first moving the antennas all over the place, then by moving the whole systems all over the place, but no matter what we did we could not get all of them to work reliably, which was a problem since there was no way to know if the clocks were not locking because of the obstructions, or if it was because they were actually broken. At about 9:00pm I threw up my hands and called the whole thing off. We packed all of the equipment back up and went home.
2018-03-05