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CONCLUSIONS facies assemblages adjacent to the Western Eberhart-Phillips, D., Reyners, M., Bannister, S.,
The integration of surface and subsurface Fiordland Orthogneiss in southwest Fiordland, Chadwick, M., and Ellis, S., 2010, Establishing
data sets from southwest New Zealand New Zealand: Journal of Metamorphic a versatile 3-D seismic velocity model for New
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shows how the history of deformation, 10.1111/j.1525-1314.2009.00822.x. v. 81, no. 6, p. 992–1000, https://doi.org/
exhumation, and fault-related topographic Allibone, A.H., Jongens, R., Turnbull, I.M., Milan, 10.1785/gssrl.81.6.992.
growth above a young ocean-continent L.A., Daczko, N.R., De Paoli, M.C., and Haines, S., Lynch, E., Mulch, A., Valley, J.W.,
subduction zone is linked to events Tulloch, A.J., 2009b, Plutonic rocks of western and Pluijm, B.V.D., 2016, Meteoric fluid
occurring near the base of the continental Fiordland, New Zealand: Field relations, infiltration in crustal-scale normal fault
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geochemistry, correlation, and nomenclature:
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40 Ar/ Ar dates show that crustal-scale Geophysics, v. 52, p. 379–415, https://doi.org/ neoformed clays in brittle fault rocks:
reverse faults reactivated two ancient shear 10.1080/00288306.2009.9518465. Lithosphere, v. 8, p. 587–600, https://doi.org/
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zones at 8–7 Ma, placing an irregular slice Andico, S., Schwartz, J.J., Tulloch, A., Turnbull, Jiao, R., Herman, F., and Seward, D., 2017, Late
of Cretaceous lower crust up and to the east R., Klepeis, K., Miranda, E.A., Kitajima, K., Cenozoic exhumation model of New Zealand:
and Ringwood, M.F., 2017, Oxygen isotope
over the middle and upper crust. The size, mapping reveals a crustal-scale structure Impacts from tectonics and climate: Earth-
age, location, and style of these faults within the Median Batholith, Fiordland, New Science Reviews, v. 166, p. 286–298,
suggest that they formed as a direct Zealand: Geological Society of America https://doi.org/10.1016/j.earscirev.2017.01.003.
consequence of a Late Miocene collision Abstracts with Programs, v. 49, no. 6, Kissling, E., and Schlunegger, F., 2018, Rollback
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between the leading edge of the subducting Betka, P.M., and Klepeis, K.A., 2013, Three- Alps: Tectonics, v. 37, p. 1097–1115,
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horizontal mass transfer, and the initiation of
~100 km depth, localized shortening and https://doi.org/10.1002/tect.20068. extension in the hot lower crustal root of a
caused the subducting slab to steepen to Bhattacharya, S., Kemp, A.I.S., and Collins, continental arc, Fiordland, New Zealand:
W.J., 2018, Response of zircon to melting and
vertical. It also drove the reactivation of metamorphism in deep arc crust, Fiordland Lithosphere, v. 8, p. 116–140, https://doi.org/
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imbrication and 12–15 km of vertical inheritance in cordilleran granites: Liu, L., 2015, The ups and downs of North
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geochemical analyses suggest that the Blattner, P., 1976, Replacement of hornblende by Reviews of Geophysics, v. 53, p. 1022–1049,
reverse faults penetrate the entire crust and garnet in granulite facies assemblages near https://doi.org/10.1002/2015RG000489.
offset the Moho. The irregular geometry of Milford Sound, New Zealand: Contributions Liu, S., Gurnis, M., Ma, P., and Zhang, B., 2017,
the Hikurangi Plateau at depth provides a to Mineralogy and Petrology, v. 55, p. 181–190, Reconstruction of northeast Asian
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shear zones were reactivated simultaneously Bradshaw, J.Y., 1985, Geology of the northern Reviews, v. 175, p. 114–142, https://doi.org/
Franklin Mountains, northern Fiordland, New
in different places at 8–7 Ma. For the first Zealand, with emphasis on the origin and 10.1016/j.earscirev.2017.10.012.
time, this study shows when, how, and why evolution of Fiordland granulites [Ph.D. Mao, X., Gurnis, M., and May, D.A., 2017,
Subduction initiation with vertical lithospheric
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arc was uplifted, imbricated, and exhumed Bradshaw, J.Y., 1990, Geology of crystalline p. 11,349–11,356, https://doi.org/10.1002/
rocks of northern Fiordland; details of the
to the surface above the Puysegur granulite facies western Fiordland Orthogneiss 2017GL075389.
subduction zone. It also illustrates how and associated rock units: New Zealand Marcotte, S.B., Klepeis, K.A., Clarke, G.L.,
Gehrels, G., and Hollis, J.A., 2005, Intra-arc
inherited zones of crustal weakness Journal of Geology and Geophysics, v. 33, transpression in the lower crust and its
facilitate the transfer of displacements p. 465–484, https://doi.org/10.1080/00288306 relationship to magmatism in a Mesozoic
.1990.10425702.
between Earth’s surface and the upper Davy, B., 2014, Rotation and offset of the magmatic arc: Tectonophysics, v. 407, p. 135–
163, https://doi.org/10.1016/j.tecto.2005.07.007.
mantle during the early stages of subduction. Gondwana convergent margin in the New McCoy-West, J., Mortimer, N., and Ireland, T.R.,
Zealand region following Cretaceous jamming 2014, U-Pb geochronology of Permian
ACKNOWLEDGMENTS of Hikurangi Plateau large igneous province plutonic rocks, Longwood Range, New
We thank A. Tulloch and N. Mortimer at subduction: Tectonics, v. 33, p. 1577–1595, Zealand: Implications for Median Batholith–
GNS (Dunedin) for discussions and assistance. https://doi.org/10.1002/2014TC003629. Brook Street Terrane relations: New Zealand
D. Jones (Vermont) provided expertise and Decker, M., Schwartz, J.J., Stowell, H.H., Journal of Geology and Geophysics, v. 57,
assistance with the argon analyses. We thank the Klepeis, K.A., Tulloch, A.J., Kitajima, K., no. 1, p. 65–85, https://doi.org/10.1080/
Dept. of Conservation Te Anau office for access Valley, J.W., and Kylander-Clark, A.R.C., 00288306.2013.869235.
and permission to sample and two anonymous 2017, Slab-triggered arc flare-up in the Milan, L.A., Daczko, N.R., and Clarke, G.L.,
reviewers for helping to improve the manuscript. Cretaceous Median Batholith and the growth 2017, Cordillera Zealandia: A Mesozoic arc
Financial support was provided by NSF grant of lower arc crust, Fiordland, New Zealand: flare-up on the palaeo-Pacific Gondwana
EAR-1119248. Journal of Petrology, v. 58, no. 6, p. 1145–1171, Margin: Scientific Reports, v. 7, no. 1, p. 261,
https://doi.org/10.1093/petrology/egx049. https://doi.org/10.1038/s41598-017-00347-w.
Ducea, M.N., Saleeby, J.B., and Bergantz, G., Mortimer, N., Tulloch, A.J., Spark, R.N., Walker,
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