Ar-Ar age constraints on the timing of Havre Trough opening and magmatism

Abstract

The age and style of opening of the Havre Trough back-arc system is uncertain due to a lack of geochronologic constraints for the region. 40Ar/39Ar dating of 19 volcanic rocks from across the southern Havre Trough and Kermadec Arc was conducted in three laboratories to provide age constraints on the system. The results are integrated and interpreted as suggesting that this subduction system is young (<2 Ma) and coeval with opening of the continental Taupo Volcanic Zone of New Zealand. Arc magmatism was broadly concurrent across the breadth of the Havre Trough.

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New Zealand Journal of Geology and Geophysics
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Ar-Ar age constraints on the timing of Havre
Trough opening and magmatism
Richard Wysoczanski, Graham Leonard, James Gill, Ian Wright, Andrew
Calvert, William McIntosh, Brian Jicha, John Gamble, Christian Timm, Monica
Handler, Elizabeth Drewes-Todd & Alex Zohrab
To cite this article: Richard Wysoczanski, Graham Leonard, James Gill, Ian Wright, Andrew
Calvert, William McIntosh, Brian Jicha, John Gamble, Christian Timm, Monica Handler,
Elizabeth Drewes-Todd & Alex Zohrab (2019): Ar-Ar age constraints on the timing of Havre
Trough opening and magmatism, New Zealand Journal of Geology and Geophysics, DOI:
10.1080/00288306.2019.1602059
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RESEARCH ARTICLE
Ar-Ar age constraints on the timing of Havre Trough opening and magmatism
Richard Wysoczanski
a
, Graham Leonard
b
, James Gill
c
, Ian Wright
d
, Andrew Calvert
e
, William McIntosh
f
,
Brian Jicha
g
, John Gamble
h,i
, Christian Timm
b,j
, Monica Handler
h
, Elizabeth Drewes-Todd
k
and
Alex Zohrab
h
a
National Institute of Water & Atmospheric Research, Wellington, New Zealand;
b
GNS Science, Lower Hutt, New Zealand;
c
Department of
Earth and Planetary Sciences, University of California, Santa Cruz, CA, USA;
d
Vice Chancellor’sOffice, University of Canterbury, Christchurch,
New Zealand;
e
U.S. Geological Survey, Volcano Science Center, Menlo Park, CA, USA;
f
New Mexico Geochronology Research Laboratory, New
Mexico Tech, Socorro, NM, USA;
g
Department of Geoscience, University of Wisconsin–Madison, Madison, WI, USA;
h
School of Geography,
Environment & Earth Science, Victoria University of Wellington, Wellington, New Zealand;
i
School of Biological, Earth & Environmental
Sciences, University College Cork, Cork, Ireland;
j
GEOMAR, Helmholtz Centre for Ocean Research, Kiel, Germany;
k
Alaska Science Center, U.S.
Geological Survey, Anchorage, AK, USA
ABSTRACT
The age and style of opening of the Havre Trough back-arc system is uncertain due to a lack of
geochronologic constraints for the region.
40
Ar/
39
Ar dating of 19 volcanic rocks from across the
southern Havre Trough and Kermadec Arc was conducted in three laboratories to provide age
constraints on the system. The results are integrated and interpreted as suggesting that this
subduction system is young (<2 Ma) and coeval with opening of the continental Taupo
Volcanic Zone of New Zealand. Arc magmatism was broadly concurrent across the breadth
of the Havre Trough.
ARTICLE HISTORY
Received 11 February 2019
Accepted 29 March 2019
HANDLING EDITOR
Phaedra Upton
KEYWORDS
Havre Trough; Kermadec Arc;
Ar-Ar; magmatism; back-arc
basin; rifting
Introduction
The present-day Kermadec Arc and associated Havre
Trough back-arc basin is the youngest in a series of
Cenozoic volcanic arcs that have developed along the
northern New Zealand margin in response to conver-
gence of the Pacific and Australian Plates (Mortimer
et al., 2010; Herzer et al., 2011; Bassett et al., 2016).
The Kermadec Arc–Havre Trough (KAHT) subduc-
tion system is the central portion of a contiguous arc
system, with the Tonga Arc–Lau Basin back-arc system
to the north, and the Taupo Volcanic Zone (TVZ) of
continental New Zealand to the south (Figure 1)
(Smith and Price, 2006). The predecessor to the Kerma-
dec Arc, the Miocene-Pliocene Colville Arc (Skinner,
1986; Ballance et al., 1999), rifted apart in response to
rollback of the Pacific Plate (Sdrolias and Muller,
2006; Wallace et al., 2009), forming the Havre Trough
and resulting in the establishment of the modern Ker-
madec Arc front. The Colville Ridge and Kermadec
Ridge are the remnants of the Colville Arc (Figure 1).
The age of opening of the Havre Trough and estab-
lishment of the Kermadec Arc is not clear owing to a
paucity of age data. In part, this is due to the inherent
difficulty in obtaining reliable radioisotopic ages on
young, glassy, and vesicular submarine volcanic rocks
with low potassium content, and in part due to tectonic
complexity, and until recently, limited seafloor
sampling in the region. Here, we present
40
Ar/
39
Ar
ages on seafloor volcanic samples from across the
southern KAHT subduction system that have impor-
tant implications for both the age and style of opening
of the Havre Trough.
Models for opening of the Havre Trough
Several models have been proposed to explain the tec-
tono-magmatic evolution of the Havre Trough and
Kermadec Arc, but the process and timing of opening
remains contentious. Malahoffet al. (1982), based on
airborne magnetic studies and seismic lines over the
southern and central portions of the KAHT, tentatively
interpreted the Havre Trough to be undergoing spread-
ing, centred on an axial ridge. They interpreted residual
magnetic anomalies to indicate a ca. 1.8 Ma age of
opening of the basin. Wright (1993), however, inter-
preted swath mapping data as showing that at least
the southern Havre Trough lacked a medial spreading
ridge, and hence interpreted back-arc rifting rather
than spreading as the mode of extension. Further,
Wright (1993), suggested that initiation of rifting
occurred at ca. 5 Ma, although this age was constrained
by extrapolation of geodetic data on continental New
Zealand rather than on direct age data from within
the Havre Trough.
Subsequent models for Havre Trough opening
agreed that the system was rifting but have varied in
the process and style of rifting being proposed. Wright
et al. (1996) suggested that Havre Trough opening and
© 2019 The Royal Society of New Zealand
CONTACT Richard Wysoczanski richard.wysoczanski@niwa.co.nz
NEW ZEALAND JOURNAL OF GEOLOGY AND GEOPHYSICS
https://doi.org/10.1080/00288306.2019.1602059

magmatism progressed eastward with time. Parson and
Wright (1996) further argued that there was a latitudi-
nal progression from full oceanic spreading in the Lau
Basin to the north, to basin rifting in the TVZ to the
south. The southern Havre Trough was considered to
be in an intermediate phase of rifting that was concen-
trated along the axial zone of the trough. Ruellan et al.
(2003), on the basis of multibeam bathymetry and seis-
mic reflection data, concluded that the southward
propagation of spreading was oversimplified, and that
southward migration of subduction of the Louisville
Seamount Chain had effectively locked the KAHT.
They proposed that opening of the Havre Trough
was initially fast and pervasive, and then relatively
quiescent as the system became locked. Wysoczanski
et al. (2010), on the basis of morphological similarities,
suggested that the Havre Trough was in a similar state
of rifting to the Valu Fa Ridge and Western Lau Basin,
and that it also was in a state of “disorganised spread-
ing”(Martinez and Taylor, 2006) whereby diffuse
patches of extension localised in deep rifts precedes
longitudinally traceable axial ridges characteristic of
true ocean spreading systems. This model reconciled
the oceanic spreading model of Malahoffet al. (1982)
with models of rifting, and is similar to the Parson
and Wright (1996)final stage of rifting (their “Phase
4”) preceding full spreading.
Analytical methods and results
A total of 19 volcanic rocks of variable composition
dredged from across the KAHT (Table 1) have been
dated by Ar-Ar step heating. The sample set is diverse,
including samples from five arc front volcanoes, two
volcanoes in the central Havre Trough (Gill and Rapu-
hia), a deep central Havre Trough basin (Ngatoro Rift)
with a short axial ridge in its southern extent, and a
cross-arc seamount chain (Rumble V Ridge) that
spans the breadth of the Havre Trough, from Rumble
V to the Colville Ridge (Figure 2). Geochemical data
for all the samples have previously been reported,
and the source of those data, together with new Ar-
Ar ages presented here, are shown in Table 1. With
the exception of one andesite and one dacite from
the volcanic arc front, all samples are basalts or basaltic
andesites (Figure 3).
Ar-Ar analyses were performed in three laboratories
(USGS, Menlo Park; New Mexico Institute of Mining
and Technology (NMIMT), Socorro; and University
of Wisconsin-Madison), initially as four smaller and
separate studies. The datasets are combined here as
one larger study to place constraints on the age of the
KAHT (Table 1,Figure 2). All ages presented in
Table 1 include 2σuncertainties and full details of
the analytical techniques are given in the Supplemen-
tary File.
The majority of ages for the arc front volcanoes are
<0.06 Ma, although two samples, from Clark (C/1) and
Rumble III (X333) have slightly older mean ages of 0.11
Ma and 0.12 Ma respectively. Uncertainties on arc
front samples however are large, and most ages are
zero within analytical uncertainty.
Three samples from Rumble V Ridge have ages of
<0.11 Ma, overlapping those of the arc front volcanoes
within uncertainty. The Ngatoro Rift samples have
older ages between 0.20 Ma and 0.68 Ma.
To the north, two samples from Rapuhia Ridge, a
volcanic ridge extending southwest from Rapuhia vol-
cano in the centre of the Havre Trough, yielded ages of
0.05 ± 0.05 Ma and 0.11 ± 0.03 Ma. These ages are mar-
ginally older than, but within error of, ages derived
from the active volcanic arc front. They are on average
younger than the samples from Rumble V Ridge [see
above], and notably younger than most of the Ngatoro
Rift samples. Three samples analysed from Gill vol-
cano, a back-arc volcano in the Havre Trough that
lies between Rapuhia Ridge and the Colville Ridge
(Figure 1), have ages significantly older than all other
samples, at 0.88 ± 0.05 Ma, 0.97 ± 0.03 Ma and 1.19
± 0.04 Ma.
Figure 1. Tectonic setting of New Zealand and the SW Pacific
highlighting the Kermadec Arc–Havre Trough (KAHT), the
Tonga-Lau subduction system, and the Taupo Volcanic Zone
(TVZ) of continental New Zealand (red outline).
Notes: Black arrow is the relative motion of the Pacific Plate to a fixed Aus-
tralian Plate for the southern KAHT region (DeMets et al., 2010). HP = Hikur-
angi Plateau, Louisville SC = Louisville Seamount Chain, NP = Northland
Plateau, VFR = Valu Fa Ridge. Red triangles denote oceanic volcanoes of
the Kermadec Arc and Havre Trough, and the offshore TVZ (southernmost
volcano, Whakatane). Highlighted area is that of Figure 2.
2R. WYSOCZANSKI ET AL.

Table 1. Details of samples analysed in this study.
Station Location Latitude south Longitude east Depth (m) Lab Lab no. IGSN Ref. SiO
2
(wt.%) MgO (wt.%) K
2
O (wt.%) Age (Ma)
C/1 Clark 36.416 177.848 2040 NMIMT Clark #45, 6696 1 50.75 9.46 1.57 0.11 ± 0.05 P
X299 Rumble III 35.749 178.498 717 NMIMT Rumble III #1, 6692 2 52.61 4.44 0.58 0.04 ± 0.06 P
X333 Rumble III 35.715 178.528 565 NMIMT Rumble III #8, 6695 2 52.14 6.72 0.48 0.12 ± 0.08 P
X351 Rumble IV 36.131 178.024 1258 NMIMT Rumble IV #9, 6703 2 66.19 1.47 1.11 0.03 ± 0.02 P
X379 Rumble V 36.153 178.161 1619 NMIMT Rumble V#23, 6694 JBG000010 2 54.00 3.51 0.60 <0.03 P
X407 Rumble V 36.133 178.202 750 NMIMT Rumble V #26, 6704 2 53.95 3.52 0.61 0.01 ± 0.06 P
X427/A Tangaroa 36.311 178.004 1781 NMIMT Tangaroa #39, 6691 2 59.26 2.63 0.67 0.06 ± 0.07 P
X153/1 Ngatoro Rift 36.260 177.300 2640 NMIMT 11574 Ngatoro Rift, 6702 JBG00001C 3 51.01 8.22 0.41 0.20 ± 0.14 P
X158/1 Ngatoro Rift 36.154 177.428 2300 NMIMT 11580 Ngatoro Rift, 6701 3 52.04 7.05 0.52 0.60 ± 0.24 P
X185/1 Ngatoro Rift 36.660 177.150 2810 NMIMT 11616 S. Ngatoro Rift, 6693 JBG000016 3 52.41 4.86 0.55 0.35 ± 0.22 P
X168/1A Ngatoro Rift 36.258 177.573 2960 Menlo Park 10Z0107 JBG000017 3 52.84 7.38 0.60 0.68 ± 0.16 R
X690A Cross arc 35.960 177.942 1805 Menlo Park 10Z0105 JBG000001 4 47.23 14.9 0.32 <0.11 I
X682 Cross arc 35.968 178.023 1480 Menlo Park 10Z0106 JBG000007 4 51.13 8.17 0.42 <0.03 I
X696A Cross arc 35.886 177.843 1680 Menlo Park 10Z0104 JBG00000J 4 48.94 8.46 0.28 <0.07 I
015-04 Rapuhia Ridge 34.794 178.445 1910 Menlo Park 15Z0332 5 51.04 9.65 0.75 0.11 ± 0.03 P
016-01 Rapuhia Ridge 34.798 178.442 1800 Menlo Park 15Z0334 5 49.60 9.99 0.49 0.05 ± 0.05 P
012-01 Gill 34.623 178.379 1146 Menlo Park 15Z0319 5 47.91 9.30 0.46 1.19 ± 0.04 P
011-04 Gill 34.607 178.389 1700 Menlo Park 15Z0318 5 51.22 8.07 0.75 0.97 ± 0.03 P
011-A Gill 34.607 178.389 1700 Wisconsin UW93C37 JBG00001K 6 53.64 6.59 0.77 0.88 ± 0.05 P
Notes: Ages are: P = plateau ages, I = Isochron ages, R = Recoil age (see Supplementary File for details). Supplementary File contains plateau and isochron ages and plots, experimental data including K/Ca ratio, MSWDs, number of steps, and
total gas age; along with an explanation of experimental methods and machine data for individual heating steps within each experiment. Results have been recalculated to a consistent fluence monitor age equivalent to Fish Canyon sanidine
at 28.198 Ma (Menlo Park) and at 28.201 Ma (NMIMT). All errors are 2σ. For the four samples X379, X690, X682, and X696 the mean age is negative, so the positive fraction of the age is reported as a maximum value (i.e. <xx Ma), calculated as
the mean of the 2σerror. IGSN numbers are given for those samples that have been assigned numbers. Reference for geochemical analyses: 1, Gamble et al., 1997; 2, Wright & Gamble unpublished data; 3, Gamble et al., 1993; 4, Todd et al.,
2010; 5, Zohrab, 2017; 6, Todd et al., 2011. All geochemical data is reported as anhydrous, with Fe as FeOtotal (not reported here).
NEW ZEALAND JOURNAL OF GEOLOGY AND GEOPHYSICS 3

Discussion
The presented Ar-Ar ages are from samples that span
almost the entire width of the southern Havre Trough
and thus provide important constraints on the manner
and timing of its opening.
Afirst order observation is that the oldest ages
reported here, from a back-arc stratovolcano (Gill vol-
cano: Wysoczanski et al., 2010) in the western part of
the Havre Trough, are 0.9–1.2 Ma (Table 1,Figure
2). However, because Gill volcano sits on a rifted
basin floor, the implied age of rifting must be older.
This age is similar to a preferred Ar-Ar age of 1.1 ±
0.4 Ma reported for a basalt from the western Havre
Trough (Mortimer et al., 2007) sampled 450 km to
the north of, and along strike from, Gill volcano, and
to a 1.25 ± 0.06 Ma U-Pb zircon age from a tonalite
xenolith from Raoul Island (Mortimer et al., 2010).
In addition, Mortimer et al. (2007) reported an Ar-Ar
age of 1.2 Ma ± 0.8 for a basalt from the Northland Pla-
teau (Figure 1), which they considered to be related to
westernmost Colville Ridge volcanism. Together, these
ages show no evidence for magmatic activity in the
Havre Trough before c. 1.2 Ma, and as noted by
Mortimer et al. (2010) suggest that magmatism was
active across the full width of the KAHT and west of
the Colville Ridge at this time (Figure 2). Furthermore,
one of our plateau ages from Gill volcano is 875 ± 50
ka, and thus it is conceivable that the age of magmatism
for the Havre Trough is younger than 1.2 Ma, and
possibly <1 Ma.
Using the 19 new Ar-Ar ages presented in this study
and two previously reported by Mortimer et al. (2007;
2010), we now have sufficient geochronologic data to
interpret the age of the Havre Trough. In addition, Bal-
lance et al. (1999) reported eight K-Ar ages of c. 2 Ma
or younger for the Kermadec Ridge and three K-Ar
ages from the eastern Havre Trough, which were
near zero age (the oldest at 0.15 ± 0.12 Ma). These
ages for the Havre Trough are all significantly younger
than the c. 5 Ma age of rifting proposed by Wright
(1993). However, we note that all current age data
are from surficial seafloor volcanics, and future
sampling (especially from sub-seafloor drilling) may
yield older ages that would require a reinterpretation
of the results presented here.
Figure 2. Bathymetric map of the southern KAHT system,
bounded by the Colville Ridge to the west and the Kermadec
Ridge to the east. Depths on the bathymetry scale are metres
below sea level, with depths <1500 m shown as 1500 m and
depths >3500 m shown as 3500 m.
Notes: Orange triangles are volcanoes: C = Clark, G = Gill, R = Rapuhia,
RIII = Rumble III, RIV = Rumble IV, RV = Rumble V, T = Tangaroa. Numbers
in boxes denote new Ar-Ar ages (Table 1).
Figure 3. Silica content of samples analysed in this study with distance from the crest of the Kermadec Ridge.
4R. WYSOCZANSKI ET AL.

The young age of magmatism, if correct, provides
three important implications for the tectonic develop-
ment of the Havre Trough.
Firstly, magmatism and translocation of the modern
Kermadec Arc front did not occur in a monotonic east-
ward progression. Notably, there is near-zero age arc
magmatism in the central portion of the Havre Trough
at Rapuhia Ridge, and magmatism related to Rumble V
Ridge does not young to the east (Figure 4). The Rum-
ble V Ridge dates are younger in age than the Ngatoro
Rift, indicating that the ridge may have been con-
structed over the Ngatoro Rift (and if this is correct,
also the Rumble Rift), rather than being cut by rifting
as previously suggested (Wright et al., 1996).
Second, reported age data for the Havre Trough are
<1.2 Ma, and possibly <1 Ma. This is younger than, but
broadly consistent with, the 1.8 Ma age of rifting
suggested by Malahoffet al. (1982), although that
model assumed a full spreading centre, whereas more
recent tectonic models based on seafloor morphology
suggest that the Havre Trough is comprised of a num-
ber of rifts and basal plateaus (e.g. Wright, 1993;
Wysoczanski et al., 2010; Wysoczanski and Clark,
2012). These ages imply a c. 2.5-4 x faster extension
rate for the Havre Trough than the 15–20 mm yr
−1
rate suggested by Wright (1993). An age of 2 Ma
would give an average rate of c. 40–50 mm yr
−1
. Whilst
reasonably fast, this rate is not unusual for extension
rates in other intra-oceanic back-arc rifts, and is still
significantly slower than the full ocean spreading
rates of >100 mm yr-
1
occurring in the Lau Basin
and Manus Basin (e.g. Taylor and Martinez, 2003;
Heuret and Lallemand, 2005; Wallace et al., 2005).
Notably this is similar to the extension rate of c. 40–
60 mm yr
−1
seen at the southern portion of the Lau
Basin (Parson and Wright, 1996; Martinez and Taylor,
2001).
Third, opening of the Havre Trough is coeval with
initiation of TVZ magmatism and rifting at c. 2 Ma
(Wilson et al., 1995) and the TVZ rift and Havre
Trough are the continental and oceanic expression of
the same rift system (e.g. Parson and Wright, 1996).
It is unclear if rifting was occurring prior to c. 2 Ma
onshore in New Zealand: 1.8–3.9 Ma volcanism
occurred along the Maungatautari-Kaimai-Tauranga
alignment parallel to but northwest of the TVZ, as
eruptions migrated southeast from the Coromandel
area (Briggs et al., 2005). Given our ages for the
Havre Trough, and that the youngest reported age of
volcanism from the Colville Ridge is 2.6 Ma (Timm
et al., in press), this magmatism is more likely to be
related to Colville Arc magmatism rather than Havre
Trough magmatism.
The western portion of the TVZ is the oldest part of
that system (the “old TVZ”of Wilson et al., 1995, and
Wilson and Rowland, 2016), and rifting is now
focussed more to the east and along a central rift, var-
iously defined as the “young TVZ”and “modern TVZ”
(Wilson et al., 1995; Wilson and Rowland, 2016),
Ruaumoko Rift (Rowland and Sibson, 2001) and the
Taupo Rift (Villamor and Berryman, 2006). Whilst
young arc magmatism is broadly occurring across the
Havre Trough (Figure 4) we have insufficient data to
identify any age progression of rift-related magmatism
across the Havre Trough. It remains uncertain if east-
ern Havre Trough rift magmatism is younger than
Figure 4. Ar-Ar ages of Havre Trough samples (Table 1) with distance from the Kermadec Ridge crest.
Notes: Error bars show 2 sigma uncertainties. Black diamonds are K/Ar ages of Ballance et al. (1999) from Kermadec Ridge and Havre Trough samples at least
300 km north of samples presented here. Grey square at ∼80 km is an Ar-Ar preferred age for a basalt from the Havre Trough (Mortimer et al., 2007). Grey
square at 0 km is a U-Pb age of zircon from a tonalite from Raoul volcano (Mortimer et al., 2010), 600 km to the north of the study area, where the modern arc
front sits on the Kermadec Ridge (Figure 1).
NEW ZEALAND JOURNAL OF GEOLOGY AND GEOPHYSICS 5

western Havre Trough rift magmatism, and so akin to
the old and young/modern TVZ regions, respectively.
The present state of extension/rifting of the Havre
Trough remains uncertain. In the case of the Ngatoro
Rift, the ages presented here indicate prolonged magma-
tism over at least 0.4 Ma, and that the rift is not presently
magmatically active at the seafloor. Importantly though,
there is extensive shallow seismic activity (<13 km deep)
within the Ngatoro Rift (de Ronde et al., 2007). Regional
moment tensor analysis for recent (2003–2012) shallow
(<33 km) earthquakes in the southern Havre Trough
show extension as well as strike slip movement (Ristau,
2014). At first order the shallow extensional seismicity in
the Ngatoro Rift and elsewhere in the Havre Trough
indicates present-day extension/rifting of the trough.
Magmatic rift intrusives (e.g. dykes) may also be con-
temporaneous, however the absence of present day
surficial extrusives and lack of hydrothermal activity
suggests that seafloor, or near seafloor, rift magmatism
is not occurring at the present day.
Conclusions
New Ar-Ar ages presented here, coupled with other pub-
lished radioisotopic ages from the literature (Ballance
et al., 1999;Mortimeretal.,2007,2010), suggest that
opening of the Havre Trough initiated <c. 2 Ma, and per-
haps as recently as c. 1 Ma. The oldest ages occur on the
margins of the basin and significant young arc magma-
tism occurred across the central Havre Trough. The tim-
ing of initiation of magmatism is coeval with that of the
TVZ. The caveat to our age constraints is that all samples
are surficial and there are no ages for samples within
c. 25 km of the Colville Ridge (Figure 4).
Our results show that there has been arc and rift-
related magmatism across the entire southern Havre
Trough within the last c. 1 Ma, both within rifts (e.g.
Ngatoro Rift) and constructing large stratovolcano
cones such as Gill and seamounts of Rumble V Ridge
(Wright et al., 1996; Todd et al., 2010). This, together
with the >4 km water depth in the deepest parts of
the basin, is more consistent with distributed rifting
across the basin than ocean spreading. Whether there
are differences in age between rift-related magmas
erupted at different depths, or distance across the
basin, or distance northward from New Zealand, is
important for understanding the tectonic evolution of
the basin but remains to be discovered. Our experience
shows that
40
Ar/
39
Ar ages can be obtained for the chal-
lenging Havre Trough samples, but that sample selec-
tion and treatment are important considerations.
Acknowledgements
The authors would like to thank Erin Todd for his internal
review, and Roger Briggs and an anonymous reviewer for
their helpful reviews. USGS disclaimer: Any use of trade,
firm, or product names is for descriptive purposes only
and does not imply endorsement by the U.S. Government.
Funding
RW was funded by the Ministry of Business, Innovation and
Employment (MBIE), Strategic Science Investment Fund
(SSIF) programme and Marine Geological Processes and
Resources (COPR1902). CT received funding from the Euro-
pean Union’s Horizon 2020 research and innovation pro-
gramme under the Marie Skłodowska-Curie grant
agreement #79308.
ORCID
Richard Wysoczanski http://orcid.org/0000-0002-7941-
1608
Ian Wright http://orcid.org/0000-0002-6660-0493
Monica Handler http://orcid.org/0000-0001-7095-0835
Elizabeth Drewes-Todd http://orcid.org/0000-0003-0692-
3714
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