1
ESM 1 Sampling site information for material used in this study. Stratigraphic information for tephras: Oruanui
fall units from Wilson (2001), Taupo units based on (Wilson 1993). In parentheses abbreviations used for
graphs listed in same order as units. *additional samples not included in all analyses.
Distance NZTMd
NZTM
Localitya
Sample IDb
(km)c
Easting
Northing
Oruanui tephra
2751
unit 3 (a11)
11
1830291
5523694
235
unit 3 (a26)
26
1865602
5726716
2787
unit 3 (a39)
39
1881527
5759321
1624
units 3, 6, 7 base, 7 top, 8
81
1923932
5743294
(a81, d81, e81, f81, g81 & ef81 mean 7 base
“
“
“
“
& top of unit7)
2272
units 3, 5 base, 5 top, 6, 8 base, 8 top
102
1920321
5627278
(a102, b102, c102, g102, h102) bc102 &
“
“
“
“
gh102 means of base & top of units 5 & 7.
2026
unit 8 (g111)
111
1957639
5667841
2029
units 3, 8 (a124 & g124)
124
1970657
5664044
2024
unit 8 (g137)
137
1985074
5668159
2041
Sample No. 2552 (C52)
850
C.I. 339.0
C.I. 676.0
2048
Sample No. 2570 (C70)
850
C.I. 364.3
C.I. 676.0
2051
Sample No. 2590 (C90)
850
C.I. 357.2
C.I. 649.5
Paleolake huka sediment clasts in proximal Oruanui ignimbrite (eruptive units 5,9 & 10)
730
Sample No. R843 (H3)
22
1864139
5685888
1574
Sample No. R845 (H5)
21
1861438
5685785
1575
Sample No. R844 (H4)
15
1856231
5689683
Sedimentary layers enclosing the Oruanui tephra
2048
Peat above volcanic ash (Cpt)
850
C.I. 364.3
C.I. 676.0
2272
*Paleosol below volcanic ash (Psol)
102
1920321
5627278
In situ Huka Falls formation
HFFcpk
*Paleolake sediment, near Huka Falls, NZ
(0)
1868705
5717426
Primary Taupo volcanic ash deposite
Hatepe (Y3) original sample (Tp0) level
2398
22
1868024
5706405
unknown
2398
*Hatepe HA1 (Tp1) 0-7 cm above unit Y4
22
1868024
5706405
2398
*Hatepe HA2 (Tp2) 13-15 cm above unit Y4 22
1868024
5706405
2398
*Hatepe HA3 (Tp3) 42-46 cm above unit Y4 22
1868024
5706405
2398
*Hatepe HA4 (Tp4) 54-59 cm above unit Y4 22
1868024
5706405
2398
*Hatepe HA5 (Tp5) 74-76 cm above unit Y4 22
1868024
5706405
2398
*Rotongaio (Y4) 0-7 cm above Hatepe
22
1868024
5706405
Pre-Oruanui & Oruanui Taupo sourced tephra
PEP-97-1
Okaia, PEP core, 19 m depth (OkB)
125
1916900
5589325
PEP-97-1
Oruanui, PEP core, 18 m depth (B125)
125
1916900
5589325
Post-glacial lake sediments from Taupo Volcanic Zone
L1133
L. Taupo, pre-European, (L.T1)
(0)
1856900
5704700
L1133
L. Taupo, mixed Holocene, (L.T14)
(0)
1856900
5704700
E1
*L. Okataina, post CE 1886, (L.O.)
(0)
1898875
5776180
RC 15
*L. Rotoiti, post CE 1314, (L.R.).
(0)
1902600
5784240
Pre-Oruanui c. 100 ky B.P lake sediments from Taupo Volcanic Zone
P35619
Diatomite, Pryces farm, (DPy)
(0)
1877755
5748915
P64976
*Diatomite, nr Parsons Rd, (DMa)
(0)
1873076
5753642
a
Locality numbers for Oruanui tephra are equivalent to those used in Wilson (2001).
b
Individual eruptive units were analyzed separately where possible. For example, Oruanui, units 5, 7 and 8
the basal upper portions were sub-sampled. Oruanui tephra from Chatham Island was sampled in bulk, but
inferred to principally include units 9 and 10 (Wilson 2001).
c
Distance given in approximate kilometers from diatom source. For tephra samples, this is the virtual source
of eruption, in the centre of Taupo volcano (as defined by Wilson 2001).
d
NZTM denotes New Zealand Transverse Mercator 2000 projection. Grid references with a C.I. prefix use
the Chatham Islands Transverse Mercator 1979 projection.
e
Samples were taken from several levels of the section of Taupo-Hatepe (Y3) tephra between the
underlying Hatepe plinian (Y2) unit and the overlying Taupo-Rotongaio (Y4) tephra (Wilson 1993).
2
ESM 2 Methods
The weights of processed samples ranged from 0.5-1 gm for the cores of Holocene lake
sediments (Rotoiti, Okataina and Taupo) to 1-2 gm for most Oruanui tephra samples, through
~10 gm for tephras from Lake Poukawa to ~50 gm for the 1.8 ka Taupo tephra. Tephra
samples were sieved through 63 μm mesh to remove coarse material before further
processing. All the samples treated with hydrogen peroxide to disaggregate them and to
remove organic matter. After the initial reaction had calmed down they were heated to 80 °C
for a few hours, to complete the reaction. Hydrochloric acid was added to lake sediment
samples to remove any calcareous matter. Samples were thoroughly washed with distilled
water. Some of Taupo tephra (Hatepe, Tp1 to Tp5) samples proved to have sparse diatoms
and be very rich in fine silt and clay. To further concentrate diatoms they were sieved
through 6μm mesh cloth, retaining the coarser fraction. It was then possible to measure 100
specimens of Aulacoseira for morphometrics. Analysis of species content was based on the
mount made earlier of Taupo tephra material (Tp0, Y3 see Table ESM 1) from the same
section.
Siliceous biogenic remains in tephra and paleolake Huka sediment samples were
further concentrated by density separation using sodium polytungstate (at a density of 2.20 g
cm-3). All processed samples were mounted onto glass coverslips with Naphrax mountant
(refractive index 1.65). Species composition was determined by counting diatoms under a
Leitz Diaplan differential interference contrast microscope at x400 or x1000 magnifications.
At least 250 (usually 300) whole and significant fragments of diatom valves were identified
to species level in each sample – these included identifiable fragments such as ends or centres
of valves. For Aulacoseira ambigua, whole valves were substantially intact, with at most,
minor chips out of their collums (Fig. ESM 1). In contrast, the significant fragments had
fragmentary mantles, but with either sulcus or disc present. For Cyclostephanos
novaezealandiae, whole valves could have lost connecting bands and part of their mantle
edge, but retained a complete set of forked ribs, whereas significant fragments included most
of the centre of the valve. For Discostella stelligera, whole valves appeared intact, whereas
significant fragments included the whole centre of a valve.
Populations of Aulacoseira valves were analysed by measuring valve heights (total
height including collum) and diameters of 100 whole Aulacoseira valves in each sample
(only 70 in the peat sample). Measurements were taken from valves lying in girdle view (See
ESM 3).
3
ESM 3. Aulacoseira, Cyclostephanos and Discostella valves
ESM 3 Diagram and micrographs showing features of Aulacoseira, Cyclostephanos
novaezealandiae, and Discostella stelligera, including features used to distinguish ‘whole’,
‘significant’, and uncounted ‘insignificant’ fragments. (a) Diagram of Aulacoseira filament in girdle
view illustrating features mentioned in text, (grey parts not in focus, i.e., not in transapical plane). (bk) Light microscope photographs: (b) example of a whole A. ambigua separation valve, showing
sulcus and vertical grooves; (c) significant fragment of A . ambigua, valve; (d) fragment considered
significant for composition but not morphometry; (e) insignificant fragment, which is part of an
Aulacoseira collum. (f-h) Examples of C. novaezeelandiae: (f) two whole valves – the upper
example is intact, the lower one still retains all of its original ‘forks’; (g) significant fragment, which
includes a recognizable portion of the centre; (h) insignificant fragment, due to absence of centre. (ik) Examples of D. stelligera: (i) whole intact valve; (j) significant fragment, with centre present; (k)
insignificant fragment, preserving too little of the centre.
4
Aam
Ach
Acr
Acs
Ads
AgA
AgN
AmL
AmV
AnS
Ava
CaB
Cas
CmN
Cnz
CoN
CoP
CpS
CvP
CyM
CyS
Dco
DpS
Dst
Ead
Emi
Eng
Eso
EuB
EuF
EuL
EuM
FcV
FfV
FrR
FrV
GoA
GoP
Gyr
HaA
Hip
Kcl
Lmu
MuG
Mvar
Nci
1
1
1
(1)
1
3
3
2
2
1
3
(2)
2
4
1
3
3
3
2
4
2
3
4
3
3
2
3
3
(3)
4
3
1
4
5
2
4
Taxon
Aulacoseira ambigua (Grunow) Simonsen
Achnanthes sensu lato
Aulacoseira italica (Ehrenberg) Simonsen [syn. A.crenulata]
Aulacoseira crassipunctata Krammer
Aulacoseira distans (Ehr.) Simonsen
Aulacoseira granulata var. angustissima (O. Müller) Simonsen
Aulacoseira granulata (Ehr.) Simonsen
Amphora libyca Ehrenberg
Amphora veneta Kützing
Anomoeoneis sphaerophora (Ehr.) Pfitzer
Aulacoseira valida (Grunow) Krammer
Caloneis cf. bacillum (Grunow) Cleve
Cymbella aspera (Ehrenberg) H. Peragallo
Cymbella novaezealandiana Krammer
Cyclostephanos novaezeelandiae (Cleve) Round
Cocconeis neodiminuta Krammer
Cocconeis placentula Ehrenberg & varieties
Cymatopleura solea (Brébisson) W. Smith
Cavinula pseudoscutiformis (Hustedt) Mann & Stickle
Cyclotella meneghiania Kützing
Cyclotella striata (Kützing) Grunow
Diadesmis contenta (Grunow ex V. Heurck) Mann
Diploneis cf. subovalis Cleve
Discostella stelligera (Cleve et Grunow) Houk & Klee
Epithemia adnata (Kützing) Brébisson
Encyonema minutum (Hilse) D.G. Mann
Encyonema neogracile Krammer
Epithemia sorex Kützing
Eunotia bigibba Kützing
Eunotia formica Ehrenberg
Eunotia bilunaris (Ehr.) Mills
Eunotia minor (Kützing) Grunow
Fragilaria capucina var. vaucheriae (Kützing) Lange-Bertalot
Fragilariforma cf. virescens (Ralfs) Williams & Round
Frustulia rhomboides (Ehr.) De Toni
Frustulia vulgaris (Thwaites) De Toni
Gomphonema angustatum (Kützing) Rabenhorst
Gomphonema parvulum (Kützing) Kützing
Gyrosigma species
Hantzschia amphioxys (Ehrenberg ) Grunow
Hippodonta capitata (Ehr.) Lange-Bertalot
Karayevia clevei (Grunow) Round & Bukhtiyarova
Luticola mutica (Kützing) D.G. Mann
Muelleria gibbula (Cleve) Spaulding & Stoermer
Melosira varians Agardh
Navicula cincta (Ehr.) Ralfs in Pritchard
D
C
E
E
D
C
C
D
D
F
F
E
F
D
D
C
E
A
E
D
D
F
E
D
E
D
E
E
E
E
F
D
E
E
E
E
B
D
E
A
E
C
A
A
F
D
Oruanui
pH
>7
c.7
(>7)
<7
>7
>7
>7
>7
>7
(<7)
>7
>7
>7
>7
>7
>7
>7
>7
>7
>7
>7
(>7)
>7
>7
c.7
<7
>7
<7
<7
6
<7
>7
c.7
<7
>7
>7
c.7
>7
c.7
>7
>7
c.7
c.7
>7
>7
5 clusters
moist
Abbrev.
ESM 4 Species abbreviations, moisture index (1 always, 2 mainly in water bodies; 3 regularly, 4 mainly in
moist places also pH from Van Dam et al. 1994, exceptions in parentheses), taxa, cluster from statistical
analysis, occurrence in 27 Oruanui tephra samples..
27
3
27
8
4
24
3
3
0
0
0
4
7
14
27
1
22
2
2
2
12
8
23
27
27
0
13
22
1
2
1
4
10
7
2
1
4
0
1
6
1
4
5
0
4
0
5
pH
c.7
>7
>7
>7
>7
c.7
c.7
>7
c.7
<7
<7
c.7
<7
>7
>7
c.7
c.7
>7
>7
<7
c.7
c.7
>7
(>7)
>7
c.7
>7
>7
c.7
c.7
c.7
>7
>7
>7
>7
>7
>7
>7
>7
>7
Taxon
Navicula cf cryptocephala Kützing
Navicula cryptotenella Lange-Bertalot
Placoneis dicephala (W. Smith) Mereschkowsky
Navicula gregaria Donkin
Nitzschia amphibia Grunow
Nitzschia nana Grunow
Nitzschia scalpelliformis (Grunow) Grunow
Nitzschia vermicularis(Kützing)Hantzsch
Nitzschia sp small size
Navicula radiosa Kützing
Navicula sp. ‘rostrate’
Navicula sm s l
Navicula tridentula Krasske
Pinnularia appendiculata (Agardh) Cleve
Pinnularia borealis Ehrenberg
Pinnularia divergentissima (Grunow) Cleve
Planothidium frequentissimum(Lange-Bertalot) Lange-Bertalot
Planothidium lanceolatum (Brébisson) Lange-Bertalot
Pinnularia cf. microstauron (Ehr.) Cleve
Pinnularia cf. maior (Kützing) Rabenhorst
Pseudostaurosira brevistriata (Grunow) Williams & Round
Pseudostaurosira parasitica (W. Smith) Morales
Pinnularia subcapitata Gregory
Pinnularia viridis (Nitzsch) Ehrenberg
Rossithidium cf. linearis (W. Smith) Round & Bukhtiyarova
Rhopalodia gibba (Ehrenberg ) O. Müller
Rhopalodia novaezealandiae Hustedt & var. ventricosa
Stauroneis acuta W. Smith
Stauroneis anceps Ehrenberg
Sellaphora bacillum (Ehrenberg) D.G. Mann
Staurosira elliptica (Schumann) Williams & Round
Sellaphora pupula (Kützing) Mereschkowksy
Stauroneis legumen (Ehrenberg) Kützing
Stauroneis phoenicenteron (Nitzsch) Ehrenberg
Staurosirella cf. pinnata (Ehr.) Williams & Round
Staurosira construens Ehrenberg
Stephanodiscus hantzschii Grunow
Stephanodiscus cf. minutulus (Kützing) Cleve & Möller
Staurosira cf. venter (Ehrenberg) Cleve & Möller
Surirella angusta Kützing
Ulnaria ulna var. acus
Ulnaria ulna (Nitzsch) Compère
Aulacoseira granulata var. muzzanensis (Meister) Simonsen
Asterionella formosa Hassall
*only mentioned briefly in text not in figures.
Oruanui
2
2
3
3
3
3
2
3
4
4
4
4
3
3
2
2
2
3
3
3
3
2
2
4
2
2
2
3
1
2
2
1
3
2
2
2
1
5 clusters
Ncr
Nct
Ndi
Ngr
NiA
NiN
NiS
NiV
NiX
Nra
Nro
Nsm
Ntr
Pap
Pbo
Pdv
PlF
PlL
PMd
Pmj
PsB
PsP
Psu
Pvi
RoL
RpG
RpN
Sac
San
SeB
Sel
SeP
Slg
Sph
Spi
StC
StH
StM
Stv
SuA
UuA
UuU
*n/a
*n/a
moist
abbrev.
ESM 4 continued
E
A
B
A
E
E
B
B
B
E
E
B
B
A
A
F
E
E
E
F
E
D
E
A
E
D
E
E
E
D
D
E
F
F
E
E
D
C
E
E
E
E
n/a
n/a
1
0
0
0
4
3
3
3
1
6
11
10
1
0
7
4
1
11
14
21
26
0
3
0
7
2
11
1
1
4
9
1
1
10
25
8
0
19
26
3
21
1
0
0
6
ESM 5 Characteristics of A. ambigua and A. granulata from the literature.
Character
A. granulata var.
muzzanensis
A. ambigua
A. granulata
A. granulata var.
angustissima
Valve diameter (µm)
9-24 [8-25]
3-12 [4-17]
4-17 [2-30]
2.5-4 [3-(5)]
Mantle height (µm)
5-13 [4-8]
5-15 [5-13] *{9-48}
4-20 [5-24]
8-20 [<35]
>0.8 to [4.5] <5
>3.2 [<11]
Ratio mantle height to
valve diameter
>1 (or less)
0.4-1.2 [0.3-0.6]
[0.75->2 (<3.6)]
†{some >5}
This study
Valve diameter (µm)
<35
4-18
Not assessed
3.5<
Mantle height (µm)
6<
8-25
Not assessed
<28
>0.19
(0.45-6.3)
Not assessed
<6.1
Ratio mantle height to
valve diameter
*Turkia and Lepistö (1999); †Siver and Kling (1997).
Values without brackets are from Spaulding et al. (2010); in square parentheses from Krammer and LangeBertalot (1991); in curly brackets, from other authors; in normal brackets, extreme values.