There are many examples of columnar basalt on the road to Whistler, but there is not adequate parking at any of the locations. The example shown here is unique and there is good parking up the Chance FSR. The cache is about 15 min from the main highway. You can pull over just above the coordinates with enough room for traffic to go by you. I accessed this cache using a non 4x4 highway car with no problems. With snow on the ground you could use a snowmobile.
Columnar jointing is a geological structure where sets of intersecting closely spaced fractures, referred to as joints, result in the formation of a regular array of polygonal prisms, or columns. Columnar jointing occurs in many types of igneous rocks and forms as the rock cools and contracts. Columnar jointing mostly occur in cooling lava flows at right angles to the flow. Some famous locations where columnar jointing can be found are the Devils Tower in Wyoming, the Devils Postpile in California and the Columbia River flood basalts in Oregon, Washington and Idaho, the Giant's Causeway in Northern Ireland and Fingal's Cave on the island of Staffa, Scotland.[2] There are many more examples.
The formation of columns happen because of contraction. Cooling basaltic lava contracts, since cooler things often takes up less space than hotter things. When things contracts, they often crack or fracture. If the contraction occurs at centers which are equally spaced then a hexagonal fracture pattern will develop, with 6-sided columns. However, if the contraction is not evenly spaced, then other shapes of fractures, like 5 or 7-sided fractures, may occur. The contraction does not need to be evenly spaced if the thickness and/or composition of the lava flow varies.
This is an under the ice eruption.
This particular example is unique as the lava extruded right against the ice during the last ice age, and there are several different flows going in different directions. These are part of the Mount Caley Lava Field which are Pleistocene (very recent) in age.
Your task is to let me know by messenger or e-mail:
1. The number of sides you see on each column. You can look up at the yellow lichen and count the sides on the columns, or you can look in the rubble below and find an intact piece.
2. The number of lava flows you see. Each is marked by a different orientation of the columnar joints.
3. Take a photo of the view with something personal in it, you, your GPS, your keys etc.