GEOPARK and REVERSING FALLS

                                             Lots to See and Learn

     I knew what an eco-museum was and, among my travels, have visited several, but a geopark was new to me. I quote from a Stonehammer pamphlet in New Brunswick, Canada: A Geopark is an area recognized by the Global Geoparks Network, supported by UNESCO, which has exceptional geological heritage. This simply means the area has a natural landscape that is good for education, has a significant scientific value, is particularly rare or it is simply beautiful to look at. Geoparks are not just about geology though, they also take in sites with interesting archaeology, wildlife and habitats, history folklore and culture, all of which are intricately linked with the underlying geology.

     The landscape of Stonehammer has been created by the collision of continents, the closing and opening of oceans, volcanoes, earthquakes, ice ages and climate change. The rocks here have been witness to the evolution of life, from the discovery of Precambrian stromatolite fossils to the ‘Cambrian Explosion’ of life to the evolution of vertebrates and the emergence of life on land.

     There are several parts to Stonehammer Geopark  and the parts we saw included the Irving Nature Park, Fallsview Park and the Reversing Rapids, the Sea Caves, and the Fundy Trail. The area where the two continents collided and split was under a harbor bridge in St. John. We rode over the bridge but did not investigate below.

Reversing Rapids, previously reversing falls

     The phenomenon of the Reversing Rapids is caused by the tremendous rise and fall of the tides of the Bay of Fundy, which at 50-feet are the highest in the world. The natural southward-facing opening of the Bay of Fundy receives the on rushing ocean tides.

     The tidewater is normal when it enters the bay. But as it travels up the bay it changes. Squeezed by the ever-narrowing sides and the constant shallowing of the bottom, it forces the water higher up the shores. The low tide running out of the bay collides with the new, incoming high tide, combining forces to make a higher wave coming in. The combination of wave forces is called resonance.

    The tides are affected by the distance of the moon from the earth. St. John River, 450 miles long, empties into the bay. At Fallsview Park, across from the Pulp Mill, is the perfect place to view the river  as it thunders through a narrow gorge. An underwater ledge, 36 feet below the surface, causes the water in the river to tumble downward into a 175-200 foot deep pool. Below the mill and under the bridge the water boils in a series of rapids and whirlpools.

    As the bay tides begin to rise they slow the course of the river and finally stop the river's flow completely. This short period of complete calm is called slack tide. This is the only time boats are able to navigate the Falls. Shortly after this slack tide, which only lasts 20 minutes, the bay tides

Low Tide from Fallview Park

become higher than the river level and slowly, at first, the river begins to flow upstream. As the bay tides continue to rise, the reverse flow gradually increases and the rapids begin to form, reaching their peak at high tide. The effect of this reversal is felt upstream as far as Fredericton, more than 80 miles inland.

     The tide rises and falls once about every 12 1/2 hours, making high tide in 6 hours 13 minutes and the same for low tide.

     Across from the pulp mill we were able to view both the high and low tides and observe the difference of the colliding tides.  We were also in the right place at the right time to see a slack tide.

Sea Caves

     At low tide we stopped to take pictures of the boats stranded on the bottom of the harbor. We couldn’t resist a picture of the two covered bridges and light house. It is the only place in the world where one can find this combination. The lighthouse now is the Visitors’ Center. We had no need to visit it as we had all the literature/pamphlets we needed.

     The caves are accessible only at low tide. We hit that at mid morning. We walked across the rocky beach and then had no choice but to wade through an ankle deep stream about 12-15-feet wide. There was no way to even think about keeping one’s feet dry. I had on my good heavy walking shoes—oh well—I was going!

   Relatively large and deep, the Bay of Fundy has molded these attractive caves -- definitely a testament to the power of the tides. The cave is of red sandstone and in itself is not really unusual as far as caves go. What interested me was the very fine chocolate color sand floor.

     The caves are another part of the Stonehammer Geopark. Part of the sedimentary outcrop in which the caves occur is Triassic in age, dating back to the time when the Atlantic Ocean was just beginning to open and the Bay of Fundy was a rift valley. The Triassic is also the time when dinosaurs first appeared on Earth. The Bay of Fundy is 120 miles long and 30 miles across. One morning, just an hour off high tide, we drove to a path that led us up and out on top of the caves where we had an entirely different perspective of the caves that now were full of water.