The Raurimu Fault is the western

Taupō rift The Taupō Rift is the seismically active rift valley containing the Taupō Volcanic Zone, central North Island of New Zealand. Geology The Taupō Rift (Taupo Rift) is a intra-arc continental rift resulting from an oblique convergence in the H ...

-bounding north–south striking normal fault complex of the Ruapehu

Graben In geology, a graben () is a depression (geology), depressed block of the Crust (geology), crust of a planet or moon, bordered by parallel normal faults. Etymology ''Graben'' is a loan word from German language, German, meaning 'ditch' or 't ...

, a seismically active area of the central

North Island The North Island ( , 'the fish of Māui', historically New Ulster) is one of the two main islands of New Zealand, islands of New Zealand, separated from the larger but less populous South Island by Cook Strait. With an area of , it is the List ...

New Zealand New Zealand () is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and List of islands of New Zealand, over 600 smaller islands. It is the List of isla ...

to the west of

Mount Ruapehu Mount Ruapehu (; English ) is an active stratovolcano at the southern end of the Taupō Volcanic Zone and North Island North Island Volcanic Plateau, volcanic plateau in New Zealand. It is northeast of Ohakune and southwest of the southern s ...

Geography

It is located near the western side of the

Tongariro National Park Tongariro National Park (; ), located in the central North Island, is the oldest national park in New Zealand and the sixth national park established in the world.Department of Conservation"Tongariro National Park: Features", retrieved 21 April ...

, mainly in the Erua Forest, where it is along the western Waimarino Stream valley. The northern surface traces of the fault commence near the

Raurimu Spiral The Raurimu Spiral, is a single-track Spiral (railway), railway spiral, starting with a Horseshoe curve (transportation), horseshoe curve, overcoming a height difference, in the central North Island of New Zealand, on the North Island Main Tr ...

and the most southern surface is over to the south just to the east of the township of

Raetihi Raetihi, a small town in the centre of New Zealand's North Island, is located at the junction of New Zealand state highway network, State Highways 4 and 49 in the Manawatū-Whanganui region. It lies in a valley between Tongariro National Park, ...

Geology

The northern end of the fault is intersected at the township of

National Park A national park is a nature park designated for conservation (ethic), conservation purposes because of unparalleled national natural, historic, or cultural significance. It is an area of natural, semi-natural, or developed land that is protecte ...

by the National Park Fault which is the more northern Taupō Rift western wall fault. Lahar deposits of late

Pleistocene The Pleistocene ( ; referred to colloquially as the ''ice age, Ice Age'') is the geological epoch (geology), epoch that lasted from to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was fin ...

(20,000 to 60,000 years ago) are offset by up to . At its southern end the fault alignment is crossed by the east west

Ohakune Fault Ohakune is a small town at the southern end of Tongariro National Park, close to the southwestern slopes of the active volcano Mount Ruapehu, in the North Island of New Zealand. A rural service town known as New Zealand's Carrot Capital, Ohaku ...

which creates just to the east of

Ohakune Ohakune is a small town at the southern end of Tongariro National Park, close to the southwestern slopes of the active volcano Mount Ruapehu, in the North Island of New Zealand. A rural service town known as New Zealand's Carrot Capital, Ohaku ...

a quite complex normal fault structure. The north south fault line resumes for a short distance from here until full transition near

into the east west alignment of the

Taupō Rift termination faults The seismically active southern end of the Taupō Rift beyond Mount Ruapehu has a number of mainly east to west orientated termination faults where the western wall Raurimu Fault and eastern wall Rangipo Fault (Desert Road Fault) terminate in ...

beyond the Ruapehu Graben. The dip slip rate is /year with the last major displacement being at 2000 ± 300 years ago. It has a normal sense of throw, and a strike and dip of 005/53°E. A deep earthquake swarm not associated directly with the fault, but which was across it defines it as a shallow fault.

Risks

The size of the characterised displacements indicates major earthquakes typical for the Taupō Rift are possible. The associated north eastern faults have been associated with a recent shallow smaller earthquake swarm.

References

{{Seismic faults of New Zealand Seismic faults of New Zealand Taupō Volcanic Zone Tongariro Volcanic Centre Ruapehu District