Wednesday 27 July 2011

A 21st Century Approach to Ground Surveying



From Field Expedition Mongolia / Valley of the Khans

A 21st Century Approach to Ground Surveying
Jul 26, 2011 by Andrew Huynh, Dr. Alex Novo and Nathan Ricklin

Continuing the tradition of years past, the VOTK team is using the data collected through the joint UCSD and National Geographic human computation system to find possibly ancient and undiscovered archeological sites. The discovery of these sites is an important part of the ongoing preservation of cultural heritage and could provide new insight into our past.

Our tech for the field increases exponentially every year we come back to Mongolia.

Aiding us in this effort is an exciting new remote controlled helicraft known as a hexacopter, created by none other than Radley Angelo, the youngest member in our team whose mechanical and electrical prowess has helped immensely throughout the exploration effort. Together with me, Andrew Huynh and the virtual explorers at home, we are taking our citizen science efforts to new heights as we explore archeological sites from above.

Since joining the UCSD graduate program I have been making sense of the millions of data points collected, pinpointing many possible sites throughout Mongolia. This seemingly massive undertaking is done utilizing the concept of clustering. For a particular site, hundreds of virtual explorers will independently click on a point boosting the "agreement" or validity of the point as an archeological site.

The hexacopter will provide us with an eye in the sky, revealing hidden structures or formations that may not be viewable with our ground team. The documentation and discovery of these new sites is vital to their preservation, so that future generations may experience the same awe and wonder of our ancient history as a very select few have today.

For scanning under the ground we have two different three dimensional imaging systems: The Electro Resistivity Tomography (ERT) instrument and a brand-new ground penetrating radar (GPR), just introduced to the US market last week. These instruments will allow us to see up to six meters under the ground to find objects and structures of historical significance.

Along with all of these tools we have the latest Trimble Total Station (not yet available on the market) that we'll use for precisely aligning the results of all scans and imagery into one cohesive visualization. Combined with in-house designed databasing and visualization technology, this will be perhaps the most technologically advanced archaeological survey yet done.

This year, Dr Alex Novo (Geostudi Astier, Livorno), is bringing new geophysical equipment to map the regions identified as highly significant by crowd sourced image analysis and historical survey.

3D ERT (Electrical Resistivity Tomography) is going to be used for detection and investigation of shallow and deep targets. The instrument is a Syscal Kid (Iris) which is a compact resistivity-meter. The system is multi-electrode switching (up to 24 electrodes). With 3D ERT we will be able to penetrate 6 meters into the ground.

Even though we already used GPR technology last year, now we will use a novel GPR array system composed by 7 antennas spaced at 12 cm with a center frequency of 200 MHz. The main aim is obtaining full-resolution GPR data of ... The system called STREAM (Swath Tomography Radar Equipment for Asset Mapping) (IDS of Italy) is a new revolutionary system for archeaological mapping (it was introduced in the US market this month).

In order to use these tools in such a difficult environment, our field system engineers have been fashioning on the fly sleds, cables, carts, stakes, and circuit boards. If our results are as good as their soldering we are in good shape!

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