This cache is placed near the first of several information signs along trail.
Your hike along the trail represents a trip through the interior of the earth formed 40 millions years ago during a major mountain-building event.
Banded or layered rocks along the trail to Angel Springs are referred to as Okanagan Gneiss. Gneiss are formed when igneous or sedimentary rocks are put under extreme pressure and high temperatures.
During this process the atoms of the different types of rock are recombined to create new minerals.
Watch a video of Gneiss rock formation
In this case the original rocks may have been granites that formed 1.8 billion to 40 million years ago. Minerals in the rocks indicate temperatures of ~500 to 600 C, at depths of 10 to 15 km. This occurred approximately 40 million years ago while volcanoes on the surface were producing rocks such as those at Mount Boucherie on the west side of Okanagan Lake.
There is a major fault underlying the lake. Rocks that once were 10 to 15 km above your head moved westward on the west-dipping fault, for tens of kilometers. The gneisses along the trail were uncovered and floated to their present elevation. The bands generally run parallel to the fault line that dips gently to the west beginning at Okanagan Lake.
To log this Earthcache it would be appreciated if you could e-mail me the answers to the following questions (you do not need to wait for a reply before logging this cache as found):
1. The rocks have parallel lines running in same direction, what do you think caused this?
2. What colours are present in the large rocks?
3. Why do you think there are different colours?
While not required, it is always appreciated if you upload any pictures of the area!