This month's Maine Geological Survey (MGS) Geologic Fact and Locality comes to you from the office instead of the field.  While we usually like to share information that gets you out from behind the computer and into the great outdoors, sometimes we feel it is beneficial to share some of our digital data products that can make your time in the field more productive.

MGS has maintained a collection of over 30,000 printed historical aerial photos in our office for decades.  They were flown for 38 different projects by other agencies at various scales and range in time from 1940 to 1996.  These photos are free to view with our stereoscope in our office and can even be checked out if needed for longer periods of time.  They can be extremely useful when trying to ascertain historical land uses or to monitor land form changes.

Beginning in the winter of 2017-2018, Christian Halsted, Director, Earth Resources Information and Amber Whittaker, Bedrock Geologist/GIS Coordinator started scanning, georeferencing and digitizing the extents of the air photo index maps and the individual air photos.  This work enabled the creation of an interactive Maine Aerial Photographs web map.  The map and table will assist you in determining what photos are available for a specific time period in a selected geographic area. MGS is working to delineate the approximate geographic footprint of each of the roughly 30,000 photographs in our collection. However, this will take time so that is why the index maps were scanned into the Aerial Photo Repository.  These will help you find the photos available in your area of interest. The table also shows the number of index map images loaded to the repository and the number of image footprint extents digitized.

Maine Geological Survey

207-287-2801 

mgs@maine.gov 

www.maine.gov/dacf/mgs