River Islands at Morrissey Park EarthCache

River Islands at Morrissey Park

Morrissey Rock Park offers travelers a small picnic site, perfect for enjoying the beautiful scenery while overlooking the Restigouche River and its islands. The park is situated on top of a cliff which houses the only train tunnel in the Maritimes’ railway system. The train tracks below the park are still in use today.

The Restigouche River is a river that flows across the northwestern part of the province of New Brunswick and the southeastern part of Quebec. William Francis Ganong identified the Mi'kmaq name for Restigouche River as Lustagooch' meaning "five-fingered river" : 17th Century French name for the river was Restgooch or Ristigouche.

The Restigouche River

The source of the Restigouche River is located at the confluence of the Little Main Restigouche River and Kedgwick River. The river is world-renowned for its Atlantic salmon fishing. Fly fishing/angling has become a significant source of revenue for many outfitters in the region and a 55-kilometre (34 mi) of the Restigouche has been designated part of the Canadian Heritage Rivers System.

The river flows in a northeasterly direction from its source in the Appalachian Mountains of northwestern New Brunswick to Chaleur Bay. It’s meander length is approximately 200 kilometres (120 mi). The estuary is 25 kilometres (16 mi) in length, extending from the river's discharge point at Dalhousie in the east to Tide Head, New Brunswick in the west and is an important stopover for sea ducks, especially black scoters and surf scoters, during migration. This estuary has been designated an Important Bird Area by the Canadian Wildlife Service.

The rocks underlying the Mount Carleton-Restigouche River area constitute part of the Gaspé Belt. The Gaspé Belt is a Late Ordovician to Middle Devonian successor basin that oversteps the margins of two major zones of deformed Cambrian to Middle Ordovician rocks. Evidence that the Gaspé Belt is mainly underlain by rocks of Dunnage affinity is provided by numerous inliers of pre-Late Ordovician volcanic and sedimentary rocks in Maine, New Brunswick and the Gaspé Peninsula.

Two faults also run through the area. The MGF, McKenzie Gulch Fault and the RGPF, Restigouche-Grand Pabos Fault. Both, along with the Appalacians formation, may have contributed to the current valley where the Restigouche river flows.

The Perennial River

Rivers are a geographical phenomena where freshwater flows through dry land from one place to another. They are natural drainage systems that naturally flow down hill, have a source, middle and a mouth. There are 13 different types of rivers of which the Rustigouche river is a perennial river.

A perennial river or permanent river never runs dry but continues to flow all through the year. The height and flow-rate of a river are influenced by seasonal change (snow, heavy rains or long drought) but will have astable source(s) that ensure their continuous flow.

River Islands

A river island is any exposed land surrounded by river water. Properly defined it excludes shoals between seasonally varying flows and may exclude semi-coastal islands such as in deltas.

These islands result from changes in the course of a river. Such changes may be caused by interactions with a tributary, or by the opposing fluvial actions of deposition and/or erosion that form a natural cut and meander. Vegetation-free shoals and mudflats may dissipate and shift or build up into such islands through deposition; the process may be assisted through artificial reinforcement or natural factors, such as reeds, palms, evergreen trees or willows, that act as obstacles or erosion barriers, so that water flows around them. Islands may be small or large, and/or covering many square kilometers.

Stream Bed and Erosion

A stream bed or streambed is the channel bottom of a stream or river, the physical confine of the normal water flow. The nature of any stream bed is always a function of the flow dynamics and the local geologic materials, influenced by that flow. The nature of the stream bed is strongly responsive to conditions of precipitation runoff. This nature of the stream bed is responsible for river paths changing, shoals, formations of islands and meanders along the river.

Stream beds are one of the most effective surface agents that erode rock and sediment. In addition to eroding the bedrock and previously deposited sediments along its route, a stream constantly abrades and weathers the individual rock and soil particles carried by its water. Hydraulic action, abrasion, and solution are the three main ways that streams erode the earth's surface.

Hydraulic action

Hydraulic action is the ability of flowing water to dislodge and transport rock particles or sediment. The greater the velocity of the water and the steeper the grade, the greater the hydraulic action capabilities of the stream. Hydraulic action is also enhanced by a rough and irregular stream bottom, which offers edges that can be “grabbed” by the current and that create uplifting eddies. The Rustigouche river has a very rocky stream bed that contributes to this action.

Abrasion

Abrasion is the process by which a stream's irregular bed is smoothed by the constant friction and scouring impact of rock fragments, gravel, and sediment carried in the water. The individual particles of sediment also collide as they are transported, breaking them down into smaller particles. Generally the more sediment that a stream carries, the greater the amount of erosion of the stream's bed. The heavier, coarser‐grained sediment strikes the stream bed more frequently and with more force than the smaller particles, resulting in an increased rate of erosion.

Circular depressions eroded into the bedrock of a stream by abrasive sediments are called potholes. The scouring action is greatest during flood conditions. Potholes are found where the rock is softer or in locations where the flow is channeled more narrowly, such as between or around boulders.

Solution

Rocks susceptible to the chemical weathering process of solution can be dissolved by the slightly acidic water of a stream. Limestones and sedimentary rock cemented with calcite are vulnerable to solution. The dissolution of the calcite cement frees the sedimentary particles, which can then be picked up by the stream's flow through hydraulic action.

To log this Earthcache visit the viewing location.  Please answer the following questions and send in a timely manner to my geocaching profile or email. Answers not received will result in deleted logs.

Questions:

1. How wide is the river at this point (GZ) to Ref A, North side (N 47° 59.996' W 66° 49.483')?

2. How many islands do you see and do they have shoals?

3. Which method caused the formation of the islands (hydraulic action, abrasion, solution)?

4. What does the bottom of the river look like?

5. How does the river bottom contribute to the formation of the island?

6. 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.