Digging Holes at Castle Rock

Friday, 3 November 2015

Anja and Jerry drove out on the Castle Rock loop road with Paul Carpenter, Chief Engineer at PASSCAL, to their test “facility” today to install a couple of seismometers for testing and burn-in. PASSCAL (Portable Array Seismic Studies of the Continental Lithosphere) is the group from New Mexico who are providing the seismometers and data loggers that we’re using on this project. Their test facility consists of an insulated storage van, which was almost as cold inside as out, just off the loop road on the way to Castle Rock, on a rise above the Ross Ice Shelf; very cold and windy there. We drove out to the site in a Mattrack, a Ford F250 with tracks replacing the wheels. (I’d like to see this thing in a Monster Truck Rally.)

Installing the instrument involved:

  1. Digging a couple of holes in the ice about 4’x4′ by 4′ deep.
  2. Leveling the bottom of the hole and placing a piece of 1’x1′ ceramic tile backed with 3″ of syntactic foam for insulation, which provides a hard, level surface to set the cylindrical instrument on.
  3. make sure that the seismo is aligned to true north (declination here at McMurdo is 144°E)
  4. then  fill in the hole, burying the instrument for a few days.

As you can see from the photos and short video below, we had a hell of a blow, and it was REALLY cold. When the door of the van opened, snow blew in and didn’t melt. We had to keep sweeping it up and throwing it out the door, not unlike sand in the desert blowing in through an open door or window. Strange.

Castle Rock in the Distance
Castle Rock in the Distance

 

Arrival at the calibration facility
Arrival at the calibration facility

It was blowing!

Digging it!
Digging it!
Seismometer in place, level, aligned to True North, and ready for burial
Seismometer in place, level, aligned to True North, and ready for burial
Paul (PASSCAL) readying the instruments
Paul (PASSCAL) readying the instruments

19

Toe Warmers are your good friends on days like this (but they don't really last 6+ hours; more like 2 hours, maybe)
Toe Warmers are your good friends on days like this (but they don’t really last 6+ hours; more like 2 hours, maybe)
Ahhhhhhhh
Ahhhhhhhh