Many geological applications like mapping, open quarry monitoring or even the study of tectonic structures, require a high resolution and a very accurate representation of the surface in order to minimize errors. High resolution satellite images or airphotos can provide the necessary basemap for such applications. Nevertheless these kinds of images are quite expensive and hard to get access to. Google Earth is easily accessible to the public, but the question that arises is, if those images can be as reliable as the original satellite images and if they can be used in their place for geological applications. The purpose of this study was to investigate Google Earth images reliability, measure their accuracy and find out if they can provide valid results and finally if they can be used for mapping applications. The region that was investigated is Markopoulo quarry in Attiki Peninsula Greece. Images were taken using Google Earth, one for each direction (North, South, East, and West) from 2004 to 2015. All the images were of the same magnification and same image quality. Subsequently, those images were georeferenced with the use of ArcGIS software. The georeference procedure was executed again using Erdas Imagine software for comparison purposes. A quickbird satellite image over the same area was orthorectified in Leica Photogrammetry Suite. From the orthorectified Quickbird image and the Google Earth images the road network was digitized and the derived vectors were compared in ARCGIS. The comparison showed remarkably low deviation which leads us to the conclusion that Google Earth images can be used as alternative basemap in many applications.