Unlike many other Google logos, Google Earth's logos don't include any text at all.
Google Earth started development in 2001. Its initial release was on June 11, 2001.
During 2015-2017 it was still being used as a secondary logo.
This logo first appeared on the Android 5.0 Lollipop Google Earth app. The non-3D version is shown at the full list of Google Apps. The non-3D version also sports a different white points and a slightly different blue used for the lines.
This logo first appeared as the app icon in the revamped Google Earth on April 18th.
Black and white variant as seen on the website.