Location
To get to this earthcache you will need to drive from
Martinbourgh to Tora which is about a comfortable 60 minute drive,
once there follow GPS to final location that will take about
another 15 minutes. Warning: Tora coastal roads are unsealed
gravel, please drive with care.
Manuwera Point Reserve is located between Tora and Tewaiti next
to Stony Bay. This area is used by a lot of campers over the
summer, please drive slowly and watch for pedestrians and also
avoid dusting out the campers
Geological Features
The west Waiarapa coast is the result of several phases of
orogeny (mountain building) that have occurred in New Zealand. The
offshore subduction zone of the Hikurangi trench has ensured a
complex anticline and syncline structure of the coastal and inlands
hills.
These hills are heavily faulted and folded with often vast
blocks of land vertically displaced or sitting oblique to the fault
that caused the uplift. The hill country West of Tora is
mid-triassic sediment that 235 to 195 millions years before present
(mybp) in age covered by mid Pliocene(5 mybp) muddy and sandy
sediment, interbedded with thin argillaceous limestone. The areas
westward movement of the plate boundary started around Miocene 22.5
to 5 mybp and is associated with the last and current orogenic
sequence (in Kaikoura Orogeny).
These hills and slopes are prone to gully erosion. The uplifted
beach platforms have alluvial fans forming on them. The uplift
continues along this coast at a rate of 1 to 2.6 mm per year
Manuwera Point shows the complex crushing and folding
deformation that has occurred Pliocene - Pleistocene and uplift of
these sediments. Look for the rocks shown in these photos, here you
can see the sequence of breaking, crushing and uplift. Manuwera
Point has being uplifted, eroded, folded and faulted, rapidly
uplifted again and had the sea level drop at the end of the last
ice age exposing the point.
These are the forces that shape this coast and point. Remember
rocks start their life horizontally and get folded , faulted and
broken by the vast tectonic forces into the different shapes and
angles that we see at this point today. This coast and New Zealand
as a whole is not a static sitting in the SW Pacific Ocean. New
Zealand is a dynamic frontline of a subduction zone with all it
associated geological wonders.
Manuwera Point Reserve you may also find the New Zealand Fur
Seals that come here to rest. Seals can be usually found from May
to October along this coast. Always respect the seals, stay at
least 2 meters away from them and make sure they have an exit point
to the sea. Seals can be dangerous!
EARTHCACHE TASKS
YOU WILL NEED TO BRING A TAPE MEASURE
At this location you will have to do the following to be able to
claim the cache. Failure to comply with the logging requirements
may result in your online log been deleted. Please forward your
answers by email, and wait for confirmation before logging. Do NOT
place any answers on the web page
1.(Optional) Take a photo of yourself or the GPS at the GZ facing
seaward, this must also include the adjacent rock face as well as
the sea and the outer rock
2. At the GZ facing towards the sea what is the strike direction of
the layers of the beds going (degrees)
Go to the following co-ordinates FZ S41 30.307 E175 31.810 and do
the following 3. At the final FZ please measure the height, width
and depth of the cliff face in front of you.
4. What are the 2 predominant colours that you see on this cliff
face
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nutcase99
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CrystalFairy |
W.E.K.A |