however i m guessing they re from u s the geological survey s geologic map of the united states 1974 by philip king and helen beikman
{"Image Software": "Google", "Image YCbCrSubSampling": "[2, 2]", "Image ExifOffset": "58", "EXIF ExifVersion": "0220", "EXIF ExifImageWidth": "1600", "EXIF ExifImageLength": "847"}