Raumanga Waterfall is a little hidden gem tucked away just outside of the Whangarei CBD in Northland New Zealand, this reserve resides in a populated area but is secluded by the bush clad valley and stream that runs through the reserve.
The reserve is accessed through Raumanga Valley Road and drive until you see the park entrance or you can access the reserve by foot from the Tarewa Park, there are no facilities here just a path that leads you through some great open parkland and follows the river side.
The track is easy going and well maintained and suitable for all the family to walk, once through the open parkland the track winds up a small incline to the first lookout of the Falls.
Raumanga Falls is a Cascade waterfall which is a series of small falls, consisting of water descending over rocks or boulders. Waterfalls in this category basically descend along a sloped surface. The evolution of a waterfall during formation, this falls could be in the early phase of its development, or the underlying hard rock layer could be sloped with water moving along that slope.
On the top level between the path and the water you will notice the Totara tree roots growing between the slabs of basalt. Root Wedging is the process in which roots grow into the cracks in rocks and force the cracks open as they continue to grow. As the roots grow they secrete organic acids, further eroding the rock and giving more space for the roots to grow into. This process, similarly to frost wedging, can cause sheets of rock to break off along areas of extensive cracking. Occasionally these roots may become fossilized. Rhizolith is the term for these roots preserved in the rock record.
The physical properties of Basalt depend on its formation. Physical properties of rocks play an important role in determining its applications in various fields. Rocks are rated on the on the Moh's Hardness Scale which rates the rocks on the scale from 1 to 10. Rocks with hardness 1-3 are soft rocks from 3-6 are medium hardness rocks and 6-10 are hard rocks.
The hardness of Basalt is 6 whereas its compressive strength is 37.40 N/mm2.
You may log this Earthcache immediately, but the answers must be sent within a week or two or the find log may be deleted.
If there is any discrepency, I will get in touch.
Do not post your answers except the photo.
1. Is the root growing through the crack a single or multiple wedge?
2. As result of the tree cracking the rock, how this could affect the waterfall going forward?
3. Over time, the river will slowly erode the basalt rock, Will this happen fast or slowly? Why?
4. As you stand in front of the waterfall, you will notice distinctive levels. What will happen to these levels over time?
5. Upload a photo from the location, include a personal item, gps, or yourself.