Maui is reputed to be pulling up Stewart Island from the sea bottom with his anchor chain whilst on his boat, the south Island.
From this place, which is also the start of the Rakiura Track in the Rakiura National Park, views of the beach and sea are gained.
On the beach just down from the chain you will notice two types of sand. Most is a white colour but there is also black sand. The presence of black sand is interesting. Black sand comes in two types.
1. Sometimes the black sand is heavy, has shiny particles, and magnetic. This indicates to a prospector the possibility of other minerals and precious stones. It indicates a placer deposit. This is an alluvial created deposit area.
2. Black sand that can have particles of basalt. When lava is cooled by water, and eroded, black sand is formed. Very soon after an eruption whole beaches can be covered with this black sand. Continual wave action can remove this heavier sand and the usual beach sand is restored mostly.
Your tasks
1. From the information about black sand, is the sand here alluvial or from basalt rock.
2. Just 5m south of the coordinates there are stairs down to beach. Measure the height of back sand in the bank just to the right of the stairs looking inland.
3. Can you give a reason for this type of black sand here?
Send your answers and observation to the CO.
A few pictures would be OK to be posted as well when you log your find.
On the Mainland check out the other end of the chain and the ECache there.