A GOOGLE EARTH CHARACTERIZATION OF THE GEOLOGIC AND TOPOGRAPHIC INFLUENCES ON BENEDICT ARNOLD'S MARCH TO QUEBEC, 1775

In 1775, Benedict Arnold proposed an attack on British-held Quebec, Canada, advocating a route up the Kennebec and Dead Rivers in Maine, down the Chaudière River in Quebec, and crossing the St. Lawrence River. Using inaccurate maps and poor intelligence, Arnold estimated completing a distance of 280 km in 20 days. In actuality, the route was a grueling 620 km that took 2 months. Beyond the necessity of hasty planning, poor boat construction, and bad weather, the geology of the route through Maine had a significant impact on this historic event.

Since the underlying bedrock played such an important role in the travel of Arnold’s expeditionary force of 1100 men and 200 bateaux along this route, locations where the expedition encountered difficulties were initially photo-documented. These sites included geologic features such as the tidally influenced Chopps, where six rivers that join the Kennebec in a large inland bay all try to exit between narrow, rocky headlands to the sea, numerous waterfalls, narrows in the Kennebec, portage routes, islands and campsites. Major portages occurred at four falls on the Kennebec; Ticonic, Skowhegan, Norridgewock and Caratunk. Beyond Caratunk Falls, the expedition left the Kennebec journeying 21 km over the Great Carrying Place to the Dead River. The Great Carrying Place portage includes a 3665 m elevational change with a 240 m rise in the first km. The portage to move all the personnel, bateaux, supplies and equipment from the Kennebec to the Dead took 5 days and required 5-7 round trips by the participants.

To geologically and topographically depict this journey, a GIS database of geologic units and structural features in Maine with lithology and age illustrated was superimposed over the aerial imagery of Google Earth. Once the underlying bedrock geology was applied as a layer, placemarks were added as .kmz files in Google Earth at the significant locations along the route. Placemarks were enhanced with text, photographs and useful URL links where applicable.

Once the bedrock geology layer was applied and the placemark .kmz files were created, a flyover of Arnold’s route though Maine was developed. The flyover aspect allowed extremely accurate visualization of the geology and topography encountered along the path of one of history’s greatest military logistical operations.