Orokonui Ecosanctuary/Geology

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  1. 170 million years ago was part of Gondwana the sedimentary rock was heated (350 degrees) and compressed and became metamorphic rock = schist
    • All of the Silverpeaks have a flattish top of schist with younger basalt on top
  2. Aotearoa separates from Gondwana 60-85 Million years ago
  3. 65 million years ago a comet hit earth and made the dinosaurs extinct
    • First marine sediments (sandstone, mudstone and limestone) appear on top of the schist
      • The sea came in from east of coast and zealandia separated off
  4. 14 million years ago there was a volcanic period with hundreds of vents all around Dunedin and thousands of eruptions = basalt (the whole sea floor is made of basalt)
    • The points that we see, eg Double Hill, Mopanui and Mihiwaka, are the roots of the volcanoes that haven’t yet eroded
    • The rocks under Orokonui are from lava flows of phonolite
    • Volcanic rocks often have sediments in them which have fossils
    • Fossils show that in this period the flora was much lusher than now
  5. 2 million years ago was an ice age with 9-10 advances during that time and interglacials in between which were even warmer than now
    • Glaciers never reached coastal Otago but very cold long winters with lots of freezing and thawing
    • The habitat was similar to sub-alpine
      • 15,000 years ago was the last ice age

Kōkōwai - Red ochre

  • Maori mixed kōkōwai with fish oil.
  • The predominant colouring agent and was used to paint large waka taua (war canoe)
    • Ochre prevented the drying out of the wood in canoes and the carvings of meeting houses
      • Estimated to last for 30 years
  • Roughly smeared over the face, especially by women, to keep off insects
  • Solid chunks of ochre were ground on a flat but rough surfaced rock to produce the powder
  • Specialist people within a hapū would be in charge of preparing the tūpāpaku (dead body)
    • They would smear the body with kōkōwai and oil, then sit it up with the knees tucked under the chin and the arms wrapped tightly around the legs
      • The crouched body was wrapped in whāriki (mats), cloaks and other finery