Google Earth KML and KMZ Files
Google Earth is just about the best possible FREE resource available to Geographers, students and teachers. With addition of KML and KMZ files, gEarth comes alive with data.
To be clear, there are three flavours of Google Earth:
Google Earth Pro: the powerful, professional, standalone desktop app, which is used to view these kml and kmz files;
Google Earth mobile app for iPad and Android: some kml files can be viewed, provided they aren't too large; and
Google Earth web app (for Chrome and Safari) viewer: much like the mobile app, only some kml files may be viewed.
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Includes layers for:
Volcanoes and Volcanic Arcs
Age of Seafloor