There are a number of unique erosional features along the west coast of Canada. Under certain conditions, offshore rocks or islands become linked to the mainland by a spit or cusp-shaped deposits called a tombolo - an Italian word from the Latin tumulus, meaning 'mound'. Whyte Island, which you see before you at GZ, is an example of a tombolo-linked island, joined to the mainland.
Tombolos are formed when waves approach an island relatively close to shore and are slowed down by the shallow water around it. The waves bend around around the sides of the island and converge on the opposite side, dropping any sand, shells or sediments between the island and the mainland. As time passes the sediments form a ridge that grows higher in elevation than sea level, eventually forming a tombolo.
NOTE: You do not need to go onto Whyte Island in order to complete the requirements for this cache. WARNING: If you do plan to visit the island consult a tide chart before you go. At high tide, you may not be able to return to the shore without getting very wet. In 2014 two tourists had to be rescued by boat when a flood tide came in. Many of the large rocks sitting on the tombolo were placed there by man in order to maintain the connection and stop the finer sediments from washing away.
Provide answers for the following:
1. Estimate the length in metres, of the tombolo from GZ to the base of Whyte Island.
2. Estimate the height of Whyte Island.
3. Describe the make-up of the sediments that have formed the tombolo.
4. (Optional) Attach a picture of the tombolo and Whyte Island.