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To create this shapefile of roads in the 227_062 and 227_063 Landsat 5 footprint,
the Imazon shapefile of roads in Pará state in 2010 was overlaid on the landsat 5 image
collected in 1986.  The image was displayed in a 453 combination, while also a tassled cap
was also performed on the image as well as a high filter pass.  These were also utilized on 
occasion to identifed cleared areas where roads of 2010 already existed in 1986.  If there was
no sign of disturbance in a linear geometric form where roads exist in 2010, it was not digitized.

Roads were digitized and included even in some cases where they were not observed images.  This 
occurred in cases where there is visible disturbance between the 1975 and 1986 image in a place without 
river access,and where there is a road connected to that place in 2010.  It was assumed in this 
case that the vegetation had grown over the trail created between 1975 and 1986 and only the location
where intensive extraction occurred was observable.