So the survey at the Isola Sacra has been running for the last three years. The area comprises an artificial island between Portus and Ostia Antica with the line of the Via Flavia running from north to south. A number of questions are being directed at the area, in particular relating to the location of the ancient coastline in the Roman period, the division and make-up of the ancient landscape an the presence or absence of buildings, workshop zones, cemeteries and other sites.
One thing that has stemmed from the survey to date is the presence of ancient canals sub-dividing the area, a small example of which appears below.
More of the same being processed at the moment suggesting the continuation of similar features. The area is marked by broad geological features also, all relating to the prograding of the Tiber delta in antiquity. For more information see www.portusproject.org/ and http://www.portusproject.org/fieldwork2007-9/regionalsurvey/results.html and http://bsr.academia.edu/StephenKay/Papers/185232/The_role_of_Integrated_Geophysical_Survey_methods_in_the_assessment_of_archaeological_landscapes_the_case_of_Portus.