Welcome to the Mountain Path
When it is fully completed, the Mountain Path will be a 5 km multi-use paved trail system that winds through the neighbourhoods and forests, leading to a host of recreational opportunities. Built with full accessibility in mind, the Mountain Path will open up this one-of-a-kind landscape to all. At present, hiking the full extent of the Mountain Path will cover about 2.1km.
When planning the Mountain Path's route through this West Coast second-growth forest the builders were cognizant of their goals and challenges. They wanted to provide a safe way for visitors of all capabilities to experience the awe and wonder of the forest, but along their chosen route they encountered some difficulties. This section of the Path is a very good example of how they handled one of those challenges.
The bedrock of the area around Cypress Provincial Park lies within the Coast Belt, one of five geological divisions that comprise the province of BC. The Coast Belt extends north to south for about 2000 km from Alaska to Washington State and averages about 150 km wide. Topographically the Coast Belt consists of the Coast and Cascade Mountains. Geologically the Coast Belt consists of 3 components:
- Terranes accreted to the continent about 95 million years ago. These terranes consist of metamorphosed volcanics formed in an island arc or oceanic plateau during Devonian to early Jurassic time (410 to 205 million years ago) known as Wrangellia.
- Granitic rocks 95 to 45 million years old that formed in a continental arc.
- Volcanic rock of the Cascade Continental or Magmatic Arc of Eocene to Holocene age (40 million years ago to present).
1 & 2 are sometimes referred to as the Coast Plutonic Complex which refers to the fact that the granitic rock component, which makes up 80% of the Coast Belt, is a complex of many granitic plutons, each up to 50 km or more long and half that in width. The larger plutons are called batholiths. Each pluton or batholith has a slightly different chemical composition. Granitic rocks have different proportions of the three main minerals, quartz, potassium feldspar (orthoclase) & calcium/sodium feldspar (plagioclase) which are used in their classification. The accessory and darker minerals, which are not used in the classification system, are biotite, amphibole &/or pyroxene. These also vary in content. In Cypress area these granitic rocks are mainly of quartz diorite & granodiorite composition although significant amounts of hornblende diorite & diorite also occur in some regions of the Park. To distinguish between quartz diorite & granodiorite in the field look for tabular white or grey plagioclase feldspar crystals which occur in higher concentration in quartz diorite.
If you look to your left and right as you pass through the cut you will notice metal rods protruding out of the rock here and there. Why are these rods there? Well, if you study the rock wall closely you can see visible layers in the face, and sometimes small cracks or fractures are apparent as well. Over the seasons water can seep into these cracks and when the temperature drops the water freezes and expands, widening these cracks into fissures, and eventually chunks of rock can begin to move.
How do you reduce the movement? That’s what the rods are for. “Bolting” is the name for the process of installing bolts (rods) through the newly-exposed rock surface, essentially anchoring the surface rock to the deeper, more stable interior rock mass rendering it less likely to move as a massive slab.
Here's how you qualify to log your find: (Please remember - do not post your answers in your "found" log. Send your answers via messaging or email)
- Find an area of the rock face where cracks or layers are visible. Which direction do the cracks or layers run?
- What do you surmise is the major rock type that this area consists of? Granitic, volcanic, or conglomerate? Why?
- Provide a photo of some characteristic of this cut through the rocks that catches your interest. Try to include yourself, or your companions, or a personal object in the photo.
I hope you have enjoyed this EarthCache and the brief pause it provided in your trek along the Mountain Path!