Yet the Berkeley archaeologists lacked two critical pieces of information for establishing a long-term excavation at the site.  First of all, the team was without any real-world data for the elevation of points on the tell.  Secondly, there was no way of consistently locating the features and objects found in the different areas of the site.


Setting GPS benchmark in limestone outcrop.  Note "X" on face of rock used as a datum for the 1980 survey.

Thus, the team started the first year by establishing a number benchmarks in a variety of locations around the tell.  In 2001 seven different locations were identified where the limestone bedrock appeared at the surface.  At each of these locations a brass pin was permanently secured to the stone.  Next, using differential GPS and a series of lengthy data collection sessions, a secure network was established which connected all of these points to one another.  Using this data the global location and elevation was determined for each of the seven benchmarks.  Working from these benchmarks, the team could now determine the precise elevation of any point atop the tell.  The first problem had been solved.

  
(left)  Brass pin at location of Benchmark 01.  (right)  GPS survey to determine location of benchmarks.

Considering its incredible accuracy, the Berkeley archaeologists could certainly have used GPS to determine the location of artifacts and features discovered through excavation or in surface surveys anywhere in the area.  However, this method of mapping finds required the constant use of computer calculations and processing.  Furthermore, while precise, the location data was rather convoluted and prevented an easy comprehension of location.  For example, knowing that Benchmark 01 is located at 3,185,906.789 m N, 297,100.151m S, and 47.482 m ASL doesn't allow the team to quickly understand that this datum point is located in the southernmost part of the tell, just south of the temple temenos.


Kinematic survey is useful for exact locations, but helps little with rough estimates of location.

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