This is the excavation unit that the students are working on. Mine is N40E35, in other words, the one in the top left side of the picture. Two people are working on the bottom left unit and one is working on the bottom right-most unit.
When we excavate we have to be careful of how much we go down and for what reason. Here we do arbitrary levels of 5 cm, which means that regardless of the artifacts recovered, we have to go down 5 centimeters across the unit. Another method we use is of natural levels, which means that if as we are digging we find a different stratigraphy, we have to stop and create another level, regardless if we went down less than the 5 centimeters we try to achieve.
I am on level 10, and have gone through about 6 different stratigraphic units.
UNIT N40 E35, in other words the coolest unit at the Mochena Borago site.
This is the total station. Without it, nothing that we are doing could be done (or rather, it could, but would take longer).
In order to know how low you have gone in an arbitrary or natural level, you must use the total station. With this machine, you shoot a point in your Excavation Unit, so that you can get the elevation of that particular area in the unit.
This is how the excavators know that they have or have yet to reach the 5cm limit of their level. I am holding a prism, this helps the total station shoot the particular point in the unit that the excavator wants to know the elevation of.
The total station also helps plot artifacts that we find in the different levels and records the data of where they are found in the space of the unit. We do this because the information of where artifacts are found relative to each other is very important for research.