Mt Fyffe Walk

You will be standing on Mt Fyffe (1602m) which forms one of the mountains in the Kaikōura Ranges. The ranges are made up of the Inland Kaikōura Range and the Seaward Kaikōura Range. They have formed as a result of uplift and strike-slip (sideways) movement along several major faults of the Marlborough Fault System which transitions between the Alpine Fault on the West Coast, and the Hikurangi Subduction Zone east of the North Island. The abrupt transition from the flat coastal plain to the steep mountain front marks the line of the Hope Fault, one of the most active faults in the country. This fault passes very close to the Mount Fyffe car park and you will have crossed it at the start of your hike up the mountain. There was a small amount of movement (about 15cm) on the Hope Fault during the Kaikōura Earthquake of 2016, observed near the car park (and also where it crosses SH1 at Half Moon Bay further north).

Another active fault (the Fyffe Fault) branches off the Hope Fault just west of Mt Fyffe, and cuts across the western slopes to cross the bare gravelly saddle at the north end of the summit ridge of Mt Fyffe.

The deep valley between where you are standing and the Seaward Range marks the line of the yet another large fault, the Kowhai Fault, which runs parallel to the Hope Fault.

These active faults are just some of the Marlborough Faults and combine to give high uplift rates of approx. 4 to 6 m per 1000 years.

The Kaikōura Ranges are formed mainly from greywacke bedrock (a type of sandstone including mudstone) from the early Cretaceous period and the flat area around Kaikōura are loose sediments (alluvium and colluvium caused by erosion of the mountains) from the Late Quaternary period and limestone from the Late Cretaceous-Paleogene periods.

Can you see where the Hope Fault lies (look for the sudden change in topography or shape of the land surface)?
Why do you think many faults follow the line of valleys in the landscape?
This landscape is dynamic! These mountains are uplifting at a rapid rate, and as a result being eroded too. Tens of thousands of landslides were triggered as a result of the 2016 magnitude 7.8 earthquake - look out for fresh landslide scars on the mountain slopes.