the road guides in Roadside Geology of Georgia contain individual geologic maps,
which are simplified versions of those in the geologic literature, tagged
with the locations mentioned in the text. This online section complements the
book’s maps through access to Google EarthTM Georgia Rocks content. Google Earth is
software you can download that allows flying
through the landscape in 3D. Once you have Google Earth loaded, try this
overview tour including
Roadside Geology page references for many of Georgia's favorite destinations. Or visit the
locations in the
overview tour using Google Maps - no installation required.
Here are the routes that appear in the book, and in green, those that are being published on this web site.
This Georgia Rocks added content consists of the following:
Š placemarks (tagged locations that become “word balloons” when clicked, usually with narrative and pictures)
Š paths (lines that mark faults and other geologic features, as well as Roadside Geology routes)
Š polygons (transparent colored areas, depicting geologic units as simplified from a digital version of the 1976 state geologic map), and
Š overlays (versions of some of the geologic maps in the book, as simplified from the literature).
The "Earth App" links
are versions best for the mobile Google Earth App - the difference being the placement
of the map legend that floats over the map. You will appreciate being able to use the maps in the field,
especially the ability to show your current location as a blue dot, but be patient: zooming around the
landscape is slower on 3G than when using a wi-fi connection.
All Georgia (5.5 MB download; not recommended for mobile devices)
The Google Earth versions include a "pull-up" version of the cross section from p. 125 of the book. The pull-up section and the
floating map legend were made with the help of Google Earth tools
developed and freely shared by Steven Whitmeyer of James Madison University.
Terranes are an important concept in this region. A terrane is an area that was widely separated from other terranes for part of its history, and was assembled with the others by the movements of plate tectonics. All the terrane boundaries in Georgia are also major faults. Identifying terranes is a work in progress, and there are minor differences between different authors’ versions. We have followed the version by Hatcher, Bream, and Merschat (2007). A Google Earth version of the book's terrane map (p. 184) together with a version of the p. 186 cross section "pulled up" along the line of section, can be downloaded here. In addition, a reconstruction of terrane original positions to accompany the book's discussion on pp. 181-185 is available here. Moving terrane polygons on Google Earth was done by moving back and forth between .kml and Excel formats, which might be made simpler today by tools on the EarthPoint website.
A difference between maps in the book and the web site is that in the book, each terrane has a different color scheme. In the online geologic maps, there is a single color scheme of rock types for the Blue Ridge and Piedmont, and heavy red lines designate the terrane boundaries.
Including geology from other sources as optional overlays – Earth
Lastly, there is a special Google Earth file on Tallulah Gorge, with Google Earth topographic profiles across it and 4 other gorges for comparison, as well as its relation to the rivers that drain the northeast corner of Georgia.