Like everything we learned this quarter, everyone’s knowledge grew with experience and practice. This was seen through all of the methods and tools we were all introduced to in the past six weeks, even the global positioning system (GPS) receivers.
Remembering back to the first time we used the Trimble Pro6H GPS receiver and data logger with ArcPad (the accompanying program) we had a difficult time. We started with a short practice session outside the Tribal Historic Preservation Office. Following along with a tutorial we were given, we were able to set up a practice file and start taking points. When it came to making a polyline and polygon we had trouble, and later all of our points were erased. This was not the first (or last time) we were able to assess and readjust. We figured out that we had more than one feature selected and that we had been using the wrong arrow to save. Once we went back outside to try again everything went smoothly and we were able to successfully take points, polylines, and polygons.
After our practice round we “leveled up” and began recording the Confederated Tribes of Grand Ronde’s Powwow grounds and the Molalla encampment site. We recorded several points, polylines, and features. We used points to record things like trees, poles, and building corners. Polylines were used for boundaries, clearings, and points of interest like flower patches and elevation changes at the Molalla site. At the Molalla site we also used the GPS system to save the points of the grids we had created for our geophysical survey of the site with the gradiometer and GPR. This will help future field school years to find the points we were working with and so they will not have to create new grids. The GPS data will also be used in conjunction with the data taken from the total station to orient it, since all of the points it has taken are not georeferenced.
In the last week of being in the field I devoted my time and focus to the GPS. During, this time we had opened up surface collection units at the Molalla site and were doing more excavation work at the schoolhouse site. We used the GPS to save the coordinates of all 48 surface collection units’ southwest, southeast, northeast, and northwest corners, resulting in 192 coordinates. The most difficult task by far were the points we recorded at the Schoolhouse site. With ArcPad you can decide how many points are taken when taking a point. The larger the number of points used, the greater the accuracy and the longer we had to hold the rod level. With the surface collection coordinates we used 20 points per point. At the Schoolhouse we used 500 points to record the datum and backsight. This was tough because the wind made it difficult to hold the Trimble rod level and standing steady made your feet feel like they were burning. But, after completing it, you feel very accomplished.
For my leadership project I chose to focus on the GPS, because it is a tool people use everyday and do not realize the possibilities it has. Archaeologists use GPS in the field with practiced experience and the last six weeks have taught me that gaining this experience and practice helps to make the process go by much faster, and easier.