Our class discussion on Tuesday covered different methods of surveying an area and what would work better in varying situations, as well as considering different factors that would have to be considered for a successful survey, like location, the coverage of the survey and it’s intensity, resources like funding, time, people, etc, and other practicality concerns. We also outlined what we would generally look for and pay attention to in a survey: artifacts and what material it was made of and features of the area such as roads, mounds, water management features, structural remains, etc.
We then put this into practice during our lab period through a practice archaeological survey of the field adjacent to the Carleton Student Farm. This demo was a pedestrian survey using fieldwalking in transecting lines to survey unit areas. This was done by arbitrarily splitting up into 3 groups: A, B, and C. A member of each group was assigned to fill out a Survey Unit forms for each surveyed unit (a survey facilitator). Another member of each group was assigned to mark the corners of each unit with waypoints on a GPS (a mapper). The remaining members of the group would be assigned to walk along transecting lines of the unit area. This fieldwalking crew was to walk due north in parallel lines spaced some distance apart. Their task would be to maintain a straight walking trajectory (it was decided these should point north because of the orientation of the target area) and to count artifacts encountered. If the artifacts were noteworthy and potentially of archaeological significance, the fieldwalker would collect them and then report their finds on the Survey Unit Form. This way, each artifact collected could be traced back to the exact transect line in which it was found.
In order to space fieldwalkers out evenly, some form of standardization in measurement was needed. Before we started, each student was to pace out 10 meters and to count for themselves, how many strides was approximately 10 meters. The fieldwalkers then spaced themselves apart evenly by 10 meters. The survey facilitator and mapper then would set flags at the corners of the unit area (the length of which was determined arbitrarily). The mapper set waypoints at those far corners too. Once the fieldwalkers reached the end of the unit area, they would report their findings to the facilitator while the mapper set two new flags (and also waypoints) some arbitrary distance due north, creating the next unit area. This process was repeated until the group reached the end of the field.
Here is Google Earth satellite imaging of the unit areas of this survey demo:
(The unit areas are color coded based on group. The flags are waypoints set by the mapper. The pink line at the bottom is 100 meters in length to show scale. North is indicated in the top right corner.)
We started Thursday’s class talking about the different ways new technology has been implemented into archaeology, with things like LIDAR scanning and GIS. LIDAR scanning allows users to see the ground through disturbances like trees and heavy foliage. GIS systems are just different programs that archaeologists can use to gain more information about the area of land they want to survey. After talking about how we can use technology to help archaeologists be better and more efficient, we had visiting professor Austin Mason give us a guest lecture on different ways 3D mapping and imagery can be used by archaeologists. 3D modeling allows archaeologists to bring parts of projects or excavations online for anyone to see and allows the people studying the area to get new perspectives on the sites where they’re digging. Austin then showed us the different types of 3D modeling. The first was manual modeling, which is basically hand drawing the models on a computer program. This method is relatively simple and inexpensive, but takes a ton of time and skill. The next type is laser scanning, which allow you to create super accurate models with impressive details, but is really expensive and hard to travel with. Procedural 3D modeling is done by writing a script in a program that generates structures and usually used for large scale models. The last form of 3D modeling that Austin walked about was photogrammetry, which is the use of computer vision algorithms to align photos calculate 3D geometry from the overlapping pixels. Relatively simple and inexpensive, and it’s replacing a lot of the other methods listed above. After taking many pictures of the object or place in question at different angles and uploading them, software finds the similar pixels and uses this information to create the object in 3D, like a panoramic photo but in 3D. After Austin demonstrated how he has used photogrammetry to create 3D models of artifacts, the class had a discussion about the survey proposals that we had prepared for the day. The class decided to survey the Pine Hill Village site since almost everyone proposed that a survey should be done there. We will do a pedestrian survey of the land on Tuesday.