Abstract
Geological information is of little value in the absence of location data regarding the site where the observation was made. Topographic maps have traditionally been used for this purpose; however, this role has now been taken over by GPS receivers. The past decade has seen the development of compact and inexpensive GPS receivers, the so-called GPS loggers, which sequentially record positional data every 1–15 seconds. Such data can be linked with, for example, image files taken by a digital camera, using common time-stamp data. The geographic coordinates (latitude and longitude) of the site where the image was taken are embedded within the image file as metadata (i.e., a geotag). This paper introduces a geotagging system designed for use with a GPS logger and digital camera, and examines the accuracy and precision of positioning by GPS logger, as well as its application in geological surveys.