This overlay contains a digital elevation model created by Dr. Gilbert N. Hanson from data originally downloaded from the Cornell University Geospatial Information Repository (CUGIR). CUGIR is an active online repository providing geospatial data and metadata for New York State. Dr. Hanson's map can be downloaded from Digital Elevation Models (DEM) for Long Island and Surroundings.

See also:
Google Earth Community: Classic Map of Long Island Geology as an Overlay
Google Earth Community: Physical Geography of New York State