Welcome to the Reversing Rapids, access is free and available 24/7; however, viewing is best from dawn to dusk. Parking is also free on the west side of the gorge. Please be careful with children as traffic can be heavy. For your safety, do not leave existing walkways or ramps. The observation deck is wheel chair accessible.
The Reversing Rapids were previously called the Reversing Falls. There were falls here thousands of years ago but now they are underwater, even at low tide. More on that later. Here we can witness the reversing of the Saint John River through the effect of the Bay of Fundy tides, which are the highest in the world. At high tide the waters of the Bay of Fundy reverses the flow of the water of the Saint John River which has flowed 450 miles to reach this point. The effect of the reversal can be seen up stream as far as Fredericton, about 60 miles. Before the last ice age the flow of the Saint John River was different than what we see today. As the glacier retreated a moraine was created at what is now Manawagonish Road, this altered the course of the river causing it to wear the gorge at Reversing Rapids. Before the glacier was completely melted and caused the ocean level to raise, the river plunger over at least three falls at the gorge. Today these underwater structures help contribute to the turbulent rapids and whirlpools that we see at low and high tides. Please take the time to witness the rapids at low and high tide. Tide information is available at most tourist information centers in the area. Now, the rest of the story.
This marine feature is only one part of the Geo-Marine Wonder of Nature to be experienced at this location. Geoscience lesson Early mapmakers recognized the similarities in the outlines of the continents of the world. In 1596, the Dutch mapmaker wrote in his work Thesaurus Geographicus that the Americas must have been torn away from Europe and Africa. He suggested that catastrophic earthquakes and floods must have been responsible for rearranging the continents. However, the suggestion that these forces actually split and moved continents had been widely dismissed. A few scientists, however, were convinced that the continents had been broken apart and moved to their present positions. Alfred Wegener was one such scientist, an astronomer and meteorologist by training, and set out to find evidence to support his theory of continental drift. In addition to detailing the similarity between the coastlines of continents on opposite sides of the Atlantic, Wegener compared collected samples of fossilized plants and animals, as well as similar rock types found oceans apart. Wagener’s theory was not widely accepted as geologists did not give full credit to a meteorologist. He died, in 1930, not being able to answer the question of how the supercontinent, Pangaea, had broken apart and the continents had moved to their current positions. By the late 1960’s, scientists had gained knowledge of mid-ocean ridges, patterns of magnetic polarity, and many other pieces of evidence that led geologists to the current theory of plate tectonics. Earth’s crust is not solid as once thought, but made up of a dozen or so tectonic plates that move independently of one another. As the supercontinent broke up to form the major tectonic plates, fragments of the tectonic plates also broke off and moved independently of the plates. These fragments are defined as terranes. A terrane is a fragment of the earth’s crust formed on, or broken off from, one piece of the earth’s crust (or tectonic plate) and attached or welded to the crust of another plate. The fragment of crust preserves its own distinctive geologic history, which is different from the crust it has become welded to. The area between a terrane and the crust that it attaches (welds to) is usually identifiable as a fault.
The Earthcache The rocks at the Reversing Rapids Gorge exhibit one of the most interesting lessons in the geological history of New Brunswick. From the observation deck, looking across the Reversing Rapids Gorge we can see the contact of two ancient geologic terranes, and the fault line boundary between them. Using the bridge as a reference point, the rocks south of the bridge are Cambrian age rocks of the Caledonia Terrane, 542 to 490 million years old. (The Caledonia Terrane is part of the Avalon Composite Terrane which is a large geological unit made up of smaller terrane fragments). North of the bridge the light gray rocks are Precambrian age from the Brookville Terrane, 750 million to 1.2 billion years old. Starting more than 500 million years ago these two fragments of crust were rifted off a continental mass (tectonic plate) centered near the South Pole and they drifted northward to collide with continental crust that is now known as North America. If only, way back then, we could have been here to witness the crustal movement that produced the Caledonia Fault, a line of weakness that separates these ancient terranes. From the observation deck it is possible to walk the path under the highway bridge toward the railway bridge, and in doing so, walk from one ancient continent to another, all of which are now part of North America. How cool is that…EH! Since this is an earthcache there is no container to find or log book to sign, only an earthscience lesson and a great experience.
Submit your answers by E-Mail before logging your find.
Logs submitted without emailing an answer will be Deleted.
If you are doing this earth cache as a group, each person logging a find must submit their own answers to each earth cache question.
To claim this earthcache as found please email through our profile the answers to the following questions. Do not include your answers in your log when you claim as found. Pictures in your log would be welcomed as a means to share with others this geological wonder.
1. How long did it take the phenomenon described in the information on the interpretative sign to take place?
2. What organization placed the interpretative sign at the observation deck on the east side of the gorge?
3. Using your GPS, what is the distance from the observation deck to the far end of the bridge? Thus the approximate width of the gorge.
4. Post a picture in your log with a personal item or hand in picture to prove you were there.
[REQUIRED] In accordance with the updated guidelines from Geocaching Headquarters published in June 2019, photos are now an acceptable logging requirement and WILL BE REQUIRED TO LOG THIS CACHE. Please provide a photo of yourself or a personal item in the picture to prove you visited the site.
Earthcaches help us discover the geological wonders of the world. Please visit www.stonehammergeopark.com to learn more information about the interesting geology of the Greater Saint John area.