by dinoflagellate cysts from Guaymas Basin, Gulf of California (Mexico)
by
Andrea Michelle Price
B.Sc., University of Victoria, 2010
A Thesis Submitted in Partial Fulfillment
of the Requirements for the Degree of
MASTER OF SCIENCE
in the School of Earth and Ocean Sciences
Andrea Michelle Price, 2012
University of Victoria
All rights reserved. This thesis may not be reproduced in whole or in part, by photocopy
or other means, without the permission of the author.
ii
Supervisory Committee
Late Quaternary climatic and oceanographic changes in the Northeast Pacific as recorded
by dinoflagellate cysts from Guaymas Basin, Gulf of California (Mexico)
by
Andrea Michelle Price
B.Sc., University of Victoria, 2010
Supervisory Committee
Dr. Vera Pospelova, (School of Earth and Ocean Sciences)
Supervisor
Dr. Thomas Pedersen, (School of Earth and Ocean Sciences)
Departmental Member
Dr. Richard Hebda, (School of Earth and Ocean Sciences, Department of Biology)
iii
Abstract
Supervisory Committee
Dr. Vera Pospelova (School of Earth and Ocean Sciences)
Supervisor
Dr. Thomas Pedersen (School of Earth and Ocean Sciences)
Departmental Member
Dr. Richard Hebda (School of Earth and Ocean Sciences, Department of Biology)
Departmental Member
A high-resolution record of organic-walled dinoflagellate cyst production in
Guaymas Basin, Gulf of California (Mexico) reveals a complex paleoceanographic
history over the last ~40 ka. Guaymas Basin is an excellent location to perform high
resolution studies of changes in Late Quaternary climate and paleo-productivity because
it is characterized by high primary productivity, high sedimentation rates, and low
oxygen bottom waters. These factors contribute to the deposition and preservation of
laminated sediments throughout large portions of the core MD02-2515. In this study we
document dinoflagellate cyst production at a centennial to millennial scale throughout the
Late Quaternary. Based on the cyst assemblages three major dinoflagellate cyst zones,
with seven subzones were established. The most dominant dinoflagellate cyst taxa found
throughout the core were Brigantedinium spp. and Operculodinium centrocarpum.
Dansgaard-Oeschger events 5-8 are inferred in the dinoflagellate cyst records on the basis
of increases in warm taxa, such as Spiniferites pachydermus. Preceding and during the
Last Glacial Maximum cysts of Polykrikos cf. kofoidii increase in abundance, responding
to oceanographic changes in the Gulf of California perhaps caused by a regression in
sea-level. Other intervals of interest are the Younger Dryas where cooler conditions are not
recorded, and the Holocene which is characterized by the consistent presence of warm
water species Stelladinium reidii, Tuberculodinidum vancampoae, Bitectatodinium
spongium and an increase in Quinquecuspis concreta. Changes in cyst assemblages,
concentrations and species diversity, along with geochemical data reflect major
millennial scale climatic and oceanographic changes.
iv
Table of Contents
Supervisory Committee ... ii
Abstract... iii
Table of Contents ... iv
List of Tables ...v
List of Figures... vi
List of Plates ... viii
Acknowledgements ...x
Author Contributions ... xi
1. Introduction...1
2. Environmental Setting...5
2.1 Physiography ...5
2.2 Modern Oceanographic and Climatic Setting of the Gulf of California ...7
3. Material and Methods ...11
3.1 Palynological Sample Preparation and Microscopy ...15
3.2 Species Diversity and Multivariate Statistical Analyses ...25
4. Results ...25
4.1 Dinoflagellate Cyst Relative Abundances, Concentrations and Accumulation Rates ...25
4.2 Statistical Analyses and Dinoflagellate Cyst Zones ...29
4.3 The Modern Analogue Technique ...32
5. Discussion ...32
5.1 The (Paleo-)productivity Signal ...33
5.2
Dinoflagellate Cyst Preservation ...34
5.3 Dinoflagellate Cyst Zones 1a to 1d (~40-22.8 ka) ...34
5.3.1 Dansgaard-Oeschger events ...34
5.3.2 Preceding the Last Glacial Maximum (27.7 - 22.8 ka) ...38
5.4 Dinoflagellate Cyst Zones 2a - 2c (22.8-11.1 ka)...39
5.4.1 The Last Glacial Maximum (~22.3-17 ka)...39
5.4.2 Heinrich Event 1 (17-16 ka)...42
5.4.3 The Bølling-Allerød (14.6-12.9 ka) and Younger Dryas (12.9-11.6 ka) ...44
5.5 Dinoflagellate Cyst Zone 3a (11.1-6.8 ka) ...46
5.5.1 The Early to Mid Holocene (~11.6-6.8 ka) ...47
6. Conclusions...49
References...52
Appendix 1...67
v
List of Tables
Table 1. Taxonomic citation of dinoflagellate cysts identified in this study. Thecate
equivalents are taken from Head [1996], Zonneveld [1997], Zonneveld and Jurkschat
[1999], Marret and Kim [2009], Matsuoka et al., [2009], and Verleye et al. [2011]…... 17
vi
List of Figures
Figure 1. (A) Map of the study area showing the locations of MD02-2515 (this study)
and other nearby cores, GGC-55/JPC-56 and DSDP-480. Bathymetric contours are in
metres. Guaymas Basin (GB) is located near the center of the Gulf. (B) The east tropical
Pacific. Approximate locations of the present day Intertropical Tropical Convergence
Zone (ITCZ) (dashed line), moisture sources (solid colored arrows), North Pacific High
(NPH) (solid oval), Sonoran Desert Low (L) (dashed ovals), and prevalent wind direction
in the Gulf (doubled-headed arrow). Features shown in red correspond to northern
hemisphere (NH) summer locations or sources (for moisture), while features shown in
blue correspond to NH winter locations………. 6
Figure 2. Cross section of the Gulf of California showing water masses and their
dominant flow direction [modified after Bray, 1988a]. Dashed blue arrows show the
predominant depth at which upwelling occurs.……… 9
Figure 3. Age-depth diagram for the 17 AMS
14C dates used to construct the age model
by Pichevin et al., [2012]. Interstadials are shown by shaded horizontal bars and
dinoflagellate cyst zones are separated by dashed lines. Heinrich events and the Younger
Dryas are highlighted in dark grey……… 13
Figure 4. GISP II δ
18O [Stuiver and Grootes, 2000], % total organic carbon (% TOC), %
biogenic silica (% BioSi), magnetic susceptibility [Cheshire et al., 2005], sedimentation
rate, lithology and structure [Beaufort et al., 2002]. Bold curves are 10 point averages.
Interstadials are shown by shaded horizontal bars and dinoflagellate cyst zones are
separated by dashed lines. Heinrich events and the Younger Dryas are highlighted in dark
grey.……….. 14
Figure 5. Relative abundances (%) of selected dinoflagellate cyst taxa. Dinoflagellate
cysts species that characterize particular zones are highlighted in color. Interstadials are
shown by shaded horizontal bars and dinoflagellate cyst zones are separated by dashed
lines. Heinrich events and the Younger Dryas are highlighted in dark grey…………... 28
Figure 6. Sedimentation rate; concentrations and fluxes for total, autotrophic and
heterotrophic taxa; ratio of heterotrophic (H) to autotrophic (A) taxa, and A/H;
Shannon-Wiener index with colored vertical lines highlighting distinct changes; and sample scores
for PCA axes 1-4, where different colors highlight changes between zones. Interstadials
are shown by shaded horizontal bars and dinoflagellate cyst zones are separated by
dashed lines. Heinrich events and the Younger Dryas are highlighted in dark
grey………... 30
Figure 7. Ordination diagram generated by principal components analysis (PCA)
showing dinoflagellate cyst taxa (black arrows) and ordination of samples (colored dots
and triangles). Abbreviations: Bspp, Brigantedinium spp; Proto, Protoperidinium spp;
Dubr, Dubrinidium spp.; CystA, Cyst type A; SBC, spiny brown cysts and Echinidinium
vii
species; CystL, Cyst type L; Psch, cyst of Polykrikos schwartzii; Pkof, cyst of Polykrikos
kofoidii; Pcfk, cyst of Polykrikos cf. kofoidii; Ocent, Operculodinium centrocarpum
sensu Wall and Dale 1966; Sben, Spiniferites bentorii; Spac, Spiniferites pachydermus;
Nlab, Nematosphaeropsis labyrinthus; Lmac, Lingulodinium machaerophorum; Eacu,
Echinidinium aculeatum; Tvan, Tuberculodinium vancampoae; Stel, Stelladinium reidii;
Qcon, Quinquecuspis contreta; Operculodinium aguinawense; Pdal, cyst of
Pentapharsodinium dalei; Pzoh, Polysphaeridium zoharyi; Sram, includes Spiniferites
ramosus and Spiniferites bulloideus; Ssp1, Spiniferites type 1; Sspp, Spiniferites spp.;
Smir, Spiniferites mirablis; Squa, includes Selenopemphix quanta and cysts of
Protoperidinum nudum; Sneph, Selenopemphix nephroides; Sund, Selenopemphix
undulata; Imap; Impagidinium spp. Eigenvalues are shown at the bottom of the figure.
viii
List of Plates
Plate 1. Bright-field photomicrographs. Scale bars are 20 µm. 1. Impagidinium
aculeatum, UVic 11-060, slide 1. 2.-3. Impagidinium paradoxum, UVic 06- 578, slide 1.
4.-5. Impagidinium sphaericum, UVic 06-597, slide 1. 6, 9. Impagidinium strialatum,
UVic 06-612, slide 1. 7-8. Nematosphaeropsis labyrinthus, UVic 06-613, slide 1……. 18
Plate 2
Bright-field photomicrographs. Scale bars are 20 µm. 1. Lingulodinium
machaerophorum, arrow shows granules on the tip of the process, UVic 11-039, slide 1.
2. Cyst of Pentapharsodinium dalei, UVic 06-576, slide 2. 3. Polysphaeridium zoharyi
showing epicystal archeopyle, UVic 11-143, slide 1. 4-5. Operculodinium centrocarpum
sensu Wall and Dale 1966 showing precingular archeopyle, UVic 06-610 slide 2, UVic
06-621, slide 1. 6. Operculodinium centrocarpum var. truncatum, UVic 06-610, slide 2.
7-8. Operculodinium aguinawense, arrow shows striated base of processes, UVic 06-634,
slide 1. 9. Operculodinium type 1., UVic 06-639, slide 1……… 19
Plate 3. Bright-field photomicrographs. Scale bars are 20 µm. 1. Spiniferites belerius,
UVic 06-639, slide 1. 2. Spiniferites bentorii, UVic 06-568, slide 1. 3.-4. Spiniferites
bentorii with reduced processes, UVic 610, slide 2. 5-6. Spiniferites type 1, UVic
06-576, slide 1.7. Spiniferites bulloideus, UVic 06-566, slide 2. 8. Spiniferites ramosus,
UVic 11-132, slide 1. 9. Spiniferites pachydermus, UVic 11-039, slide 1. 10. Spiniferites
mirabilis, UVic 11-040, slide 1. 11.-12. Spiniferites cf. hyperacanthus, UVic 06-610-2,
slide 2……… 20
Plate 4. Bright-field photomicrographs. Scale bars are 20 µm. 1. Bitectatodinum
spongium, UVic 06-619, slide 1. 2. Tectadinium pellitum, UVic 06-581, slide 1. 3.
Tuberculodinium vancampoae, UVic 11-058, slide 1. 4. Brigantedinium simplex, UVic
11-045, slide 1. 5. Brigantedinium cariacoense, UVic 11-058, slide 1. 6. Brigantedinium
spp., UVic 06-665, slide 1. 7. Dubridinium spp. UVic 06-560, slide 1. 8. Cyst of
Protoperidinium americanum, UVic 06-649, slide 1. 9. Gymnodinium spp., polygon in
white highlights the reticulation, UVic 11-134, slide 1……… 22
Plate 5. Bright-field photomicrographs. Scale bars are 20 µm. 1. Quinquecuspis
concreta, UVic 06-671, slide 1. 2. Cyst of Protoperidinium oblongum sensu Wall and
Dale 1968, UVic 11-041, slide 1. 3. Votadinium calvum, UVic 06-665, slide 1. 4.
Votadinium spinosum, UVic 06-558, slide 1. 5. Cyst of Protoperidinium nudum, UVic
11-059, slide 1. 6. Selenopemphix quanta, UVic 06-650, slide 1. 7. Selenopemphix
nephroides, UVic 11-041, slide 1. 8. Selenopemphix undulata, UVic 06-566, slide 1. 9.
Stelladinium reidii, UVic 11-057, slide 1………. 23
Plate 6. Bright-field photomicrographs. Scale bars are 20 µm. 1. Cyst of Polykrikos
kofoidii UVic 06-670, slide 1. 2. Cyst of Polykrikos schwartzii, UVic 06-611, slide 1.
3. Cyst of Polykrikos cf. kofoidii, UVic 06-552, slide 2. 4. Echinidinium aculeatum, UVic
06-543, slide 1. 5. Echinidinium granulatum, UVic 143-1, slide 1. 6. Echinidinium cf.
ix
zonneveldiae, UVic 06-644, slide 1. 7. Cyst type A, UVic 11-042, slide 1. 8. Cyst type F,
x
Acknowledgements
First and foremost I would like to thank my supervisor and mentor Dr. Vera
Pospelova for her tremendous support, encouragement, and guidance, and for first
sparking my interest in micropaleontology. I would also like to thank Dr. Kenneth
Mertens for his contributions and feedback, my committee members Dr. Tom Pedersen
and Dr. Richard Hebda for their time and willingness to serve on my thesis committee,
and Dr. Rolf Mathewes for serving as the external examiner. I am grateful to Victoria
Gray, Alanna Krepakevich, and Kristen Kennedy for their laboratory assistance and
would like to thank Manuel Bringué for his helpfulness, interesting discussions, and
introducing me to new music genres while counting at the microscope. Thank you to
Ruth Dwyer (University of Edinburgh) for sampling the core, Dr. Heather Cheshire
(University College London) for providing sediment density and magnetic susceptibility
measurements, Ellen Roosen (Woods Hole Oceanographic Institute) for providing
surface sediment samples and Dr. Terri Lacourse (University of Victoria) for discussions
about multivariate statistics. Finally, I would like to thank my family and friends for their
unwavering love and support. Funding for this project was provided by the Natural
Sciences and Engineering Council of Canada (NSERC) through grants to Dr. Vera
Pospelova, Dr. Tom Pedersen and a CGS-M scholarship to Andrea Price; a UVic
Graduate Fellowship, a UVic David Strong Research Scholarship, a UVic President’s
Research Scholarship, a Martlet Chapter IODE Graduate Scholarship for Women, and an
American Association of Stratigraphic Palynologists (AASP) Student Scholarship to
Andrea Price.
xi
Author contributions
This thesis forms the basis of a manuscript that has been submitted (June 2012) to
the journal Paleoceanography coauthored by Andrea M. Price, Kenneth N. Mertens,
Vera Pospelova, Thomas F. Pedersen and Raja S. Ganeshram.
Andrea M. Price – processed 47 samples, microscopic analysis of 178 samples,
preformed statistical analyses, made maps and figures, analyzed and interpreted the data,
and prepared the manuscript for publication.
Kenneth N. Mertens – microscopic analysis of 108 additional samples and provided
detailed comments, suggestions and corrections on the manuscript.
Vera Pospelova – initiation of the project and acquisition of samples, funding through
NSERC grants, provided advice and input into the interpretation of the data as well as
comments, suggestions and corrections on the manuscript.
Thomas F. Pedersen – provided partial funding for laboratory processing of sediments.
Raja S. Ganeshram – provided samples.
1. Introduction
Abrupt millennial scale climate fluctuations have occurred during the last glacial,
namely the quasiperiodic Dansgaard-Oeschger (D-O) events. They are best documented
by δ
18O records from the Greenland ice sheet [i.e. Dansgaard et al., 1993], where
positive excursions mark warm interstadials and occur on average ~1500 years apart
[Clement and Peterson, 2008]. During some extreme cold stadials ice rafted debris was
deposited in the North Atlantic, and these have been termed Heinrich events [Broecker et
al., 1992]. Millennial scale variability is most pronounced in the North Atlantic, but is
also observed in paleoclimate records from lower latitudes including the tropics [Voelker
et al., 2002 and references within; Clement and Peterson, 2008]. The apparent
synchronicity and global nature of these events suggests a tight coupling between shifts
in atmospheric and ocean circulation over broad areas [Behl and Kennett, 1996; Hendy
and Kennett, 1999]. Regions in the northern tropics are particularly sensitive due to
latitudinal shifts in the Intertropical Convergence Zone (ITCZ) and related shifts in
precipitation patterns [e.g. Peterson et al., 2000]. The latitudinal position of the ITCZ is
influenced by seasonal differences in temperature and incoming solar insolation, as well
as El Niño-Southern Oscillation (ENSO) variability on interannual timescales. During
warm episodes the pole-to-Equator gradient is lessened, shifting the ITCZ further north,
while the opposite occurs during cold periods [e.g. Asmerom et al., 2010].
The Gulf of California (herein referred to as the Gulf) is an excellent location to
investigate millennial scale variability during the last glacial period because it has a
monsoonal climate that is heavily modulated by the location of the ITCZ, and nearby
pressure systems such as the North Pacific High (NPH) and Sonoran Desert Low (SDL)
2
(Figure 1b). Guaymas Basin, located in the central Gulf, has the potential to be an ideal
recorder of paleoceanographic information because it is characterized by low oxygen
bottom water, seasonal patterns in upwelling and precipitation, and high primary
productivity which contribute to the deposition and preservation of laminated sediments.
Guaymas Basin has been the focus of Late Quaternary paleoclimate reconstructions,
especially over the past ~17 ka [e.g. Keigwin and Jones, 1990; Sancetta, 1995; Pride et
al., 1999; Barron et al., 2004; Dean, 2006]. These studies have provided valuable
information on past climatic and oceanographic conditions in the Northeast Pacific since
the Last Glacial Maximum (LGM). For example, Pride et al. [1999] studied nitrogen
isotopes and biogenic silica (BioSi) records from cores JPC56 and GCC55 in Guaymas
Basin and found laminated sediments with high δ
15N
organd BioSi accumulation rates
during the Bølling-Allerød (B-A), while the Younger Dryas (YD) and end of the late
glacial were characterized by non-laminated sediments, low BioSi, and lower δ
15N
org
.
They attributed these shifts to widespread changes in the extent of suboxic subsurface
waters, variations in upwelling and mixing, and/or the latitudinal migration of the ITCZ.
More recently Barron et al. [2004] analyzed geochemical, diatom and silicoflagellate
records from DSDP Site 480 from ~15 - 1 ka. Like Pride et al. [1999] they found that the
B-A was characterized by diatom rich laminated sediments, while the YD saw a decline
in biogenic silica. Barron et al. [2004] also documented an increase in CaCO
3, and the
presence of tropical diatom species that suggest reduced upwelling conditions during the
YD. In addition, there are few well-dated cores in the Gulf that extend past ~17 ka.
In this study we use dinoflagellate cysts to investigate millennial scale variability
in primary productivity and climate over the past 40 ka BP. Dinoflagellates are one of the
3
most important groups of primary producers in coastal and estuarine systems, with over
1,555 known free-living marine species worldwide [Gómez, 2005]. They are
predominately single-celled protists, and are characterized by two flagella, the presence
of unique sterols, lack of c
1chlorophyll, a unique cell wall structure and characteristic
nuclei [Dale, 1996; Fensome et al., 1996; Mudie and Harland, 1996]. Furthermore they
display a high degree of diversity both in their motile stage [Sarjeant et al., 1987] and
resting stage.
They are unique amongst other phytoplankton groups in several respects. Firstly,
dinoflagellates display a high degree of mobility. Although coccolithophores also have a
motile stage, and diatoms to some extent are able to adjust their position in the water
column, dinoflagellates actively swim and are thus more effectively mobile [Dale, 1996].
This gives them many advantages as they are able to maximize photosynthesis by
regulating their depth in the water column [Prezelin, 1987] and they can maintain their
depth at nutrient-rich oceanic fronts [Dale, 1996]. They are especially adapted to well
stratified waters where they are able to photosynthesize near the surface during the day
and migrate down into higher nutrient subsurface waters at night, thus making swimming
biologically worthwhile. Increased stratification is less favorable to diatoms and the
heterotrophic dinoflagellates that feed on them, resulting in less competition for nutrients
and may result in an increase in autotrophic taxa. Heterotrophic dinoflagellates on the
other hand tend to dominate in upwelling conditions when diatoms are abundant [i.e.
Taylor, 1987]. Secondly, dinoflagellates employ a variety of trophic strategies.
Approximately half of all dinoflagellates are heterotrophs, while many others may use
more than one nutritional strategy (mixotrophy), rather than being obligatory autotrophs
4
[Dale, 2009]. The differences in trophic structure impacts species distribution. Those
that primarily rely on photosynthesis to synthesize food are most affected by nutrient
concentrations and light levels, while heterotrophs respond more to prey availability
[Dale, 1996]. Thirdly, numerous dinoflagellate species produce an organic-walled cyst, a
dormant stage, that is highly resistant to physical, chemical and biological degradation
[Dale, 1996; Fensome et al., 1996], unlike siliceous or calcareous microfossils which are
subject to dissolution. Resting cysts are formed after sexual reproduction. The formation
of cysts has a variety of potential ecological functions including survival through adverse
environmental conditions, seeding source for the motile population, bloom initiation,
species dispersal, and increased genetic recombination [Sarjeant et al., 1987].
Dinoflagellate species have different environmental preferences and over the last
few decades cyst assemblages have been developed as tools used in paleoenvironmental
reconstructions. They are used to determine past surface temperature (SST),
sea-surface salinity (SSS), primary productivity, eutrophication, pollution, and sea-ice
coverage [e.g. Dale, 1996; Matsuoka, 1999; Rochon et al., 1999; de Vernal et al., 2001;
Marret and Zonneveld, 2003; Radi and de Vernal, 2004; Radi et al., 2007; Pospelova et
al., 2008; Dale, 2009; Zonneveld et al., 2009].
This is the first study to analyze dinoflagellate cyst records at the centennial to
millennial scale in the Northeast Pacific over the Late Quaternary. We document
variations in dinoflagellate cyst species composition and abundance over the past 40 ka in
Guaymas Basin. Our objectives are (1) to describe changes in marine primary
productivity in relation to past climatic variability, (2) to determine if dinoflagellate cyst
assemblages record millennial scale climatic and oceanographic changes in the Gulf of
5
California, (3) to compare our records to other proxies of sea-surface conditions in the
Gulf and (4) to provide further insights into the oceanographic and climatic history of the
region over the Late Quaternary.
2. Environmental Setting
2.1 Physiography
The Gulf of California is a narrow marginal sea that opens into the subtropical
Pacific Ocean. It is located between the Baja Peninsula and the northwest coast of
Mexico and is approximately 1,000 km in length and 150 km in width, reaching water
depths of over 2,500 m [Bray, 1988a] (Figure 1a). Guaymas Basin is situated
approximately in the center of the Gulf and is an elongate semi-enclosed basin that
formed via seafloor spreading [Dean, 2006]. The Rio Yaqui and Rio Matape drain into
the eastern margin of Guaymas Basin, while the Colorado River, Rio Sonora, Rio Mayo
and Rio Fuertre also drain into the Gulf, but are located further north or south of
Guaymas Basin (Figure 1a). These rivers contribute some terrigenous material into the
basin, however fluvial input of terrigenous material is thought to be minor [Baba et al.,
1991; Baumgartner et al., 1991; Thunell et al., 1993].
6
Figure 1. (A) Map of the study area showing the locations of MD02-2515 (this study)
and other nearby cores, GGC-55/JPC-56 and DSDP-480. Bathymetric contours are in
metres. Guaymas Basin (GB) is located near the center of the Gulf. (B) The east tropical
Pacific. Approximate locations of the present day Intertropical Tropical Convergence
Zone (ITCZ) (dashed line), moisture sources (solid colored arrows), North Pacific High
(NPH) (solid oval), Sonoran Desert Low (L) (dashed ovals), and prevalent wind direction
in the Gulf (doubled-headed arrow). Features shown in red correspond to northern
hemisphere (NH) summer locations or sources (for moisture), while features shown in
blue correspond to NH winter locations.
Baja C alifornia
MEXICO
Colorado River Rio Yacqui Rio MatapePacific
Ocean
Rio Mayo Rio Fuerie Rio Sonora Guaymas 55/56480Gulf of
California
2000 m 114 W 112 W 110 W 108 W 24 N 26 N 30 N 28 N 32 N 500 m 200 m GB 2515 NH winter ITCZ NH summer ITCZ NPH L L 0 30 N 15 N 15 S 120 W 110 W 100 W 90 W 80 W 70 WA.
B.
Midriff Islands 100 km7
2.2 Modern Oceanographic and Climatic Setting of the Gulf of California
The Gulf of California is the only evaporative basin adjacent to the Pacific Ocean.
It is unique in that unlike many mid-latitude evaporative basins, the Gulf of California
has net outflow at the surface (above 250 m) and inflow at depth (500-250 m) [Bray,
1988b]. Surface circulation and upwelling is strongly controlled by atmospheric systems,
where wind direction and strength determine the location and intensity of upwelling in
the Gulf [Thunell et al., 1993; Thunell et al., 1994; Douglas et al., 2007].
Water masses
There are a number of water masses present in the Gulf that impact primary
productivity and lamination preservation. The bottom water mass, the Pacific Deep Water
(PDW), is found below depths of ~1000 m in the Gulf (Figure 2). At depths between
~500-1000 m Pacific Intermediate Water (PIW) flows into the Gulf creating a persistent
Oxygen Minimum Zone (OMZ). The OMZ causes slope sediments at these depths to be
sufficiently depleted in oxygen that bioturbation is inhibited, allowing for the
preservation of laminated sediment [Cheshire et al., 2005]. The upper ~500 m involved
in thermohaline circulation consists of three layers, with inflow at 500-250 m, outflow at
250-50 m, and a surface layer (~50-0 m) that reverses seasonally with the wind direction
(Figure 2). During summer warm surface water is transported into the Gulf with
southeasterly winds (Figure 1b). In winter the opposite occurs and colder surface water is
transported out of the Gulf. Water mass formation occurs in the northern Gulf where
Subsurface Subequatorial Water (SSW) and water from the Colorado delta mix by winter
8
convection, tidal mixing, and buoyancy driven horizontal circulation, forming Northern
Gulf Water (NGW) (Figure 2) [Bray, 1988a; Pride et al., 1999]. Water mass formation in
the northern Gulf contributes significantly to high productivity in Guaymas Basin
[Baumgartner, 1987]. Upwelled water originates from the Central Gulf Water (CGW), at
a water depth of 250-50 m; thus the nutrient content of this water mass can have a
9
Figure 2. Cross section of the Gulf of California showing water masses and their
dominant flow direction [modified after Bray, 1988a]. Dashed blue arrows show the
predominant depth at which upwelling occurs.
Guaymas
Basin
NW
SE
PDW
PIW
NGW
SSW
ESW/CCW
CGW
Colorado deltaEntrance to the
Gulf of California
PDW - Pacific Deep Water
PIW - Pacific Intermediate Water
NGW - Northen Gulf Water
SSW - Subequatorial Subsurface Water
ESW - Equatorial Surface Water
CGW - Central Gulf Water
CCW - California Current Water
3000 m
1000 m
500 m
250 m
50 m
10
Climate
The Gulf of California displays strong seasonality due to a monsoonal climate
driven by atmospheric changes in circulation, in particular the locations of the ITCZ, the
NPH and the SDL (Figure 1b). Ocean dynamics are also influenced by the seasonal
locations of the these weather systems [Douglas et al., 2007]. The wind associated with
the NPH and SDL act to control surface circulation and mixing in the Gulf, as well as
cause large evaporation rates [Pares-Sierra et al., 2003]. In the modern environment
sea-surface temperatures range from ~14 °C to over 30 °C [Roden, 1958; Bray, 1988a]. The
greatest seasonal fluctuation in sea-surface conditions occurs in the northern Gulf [Roden,
1958]. In part the large seasonality in climate is caused by an almost uninterrupted chain
of 1,000-3,000 m high mountain range on Baja California, resulting in a much reduced
oceanic influence and a more continental-type climate.
In winter (November to March) winds are northwesterly (Figure 1b) and come
from over the deserts of the American southwest. They are low in humidity acting to
increase evaporation rates, and are responsible for transporting large amounts of dust into
the northern and central Gulf [Douglas et al., 2007]. These winter winds also lower SST
and promote mixing in the upper ocean, causing the thermocline to disappear and
establishing upwelling. Upwelling begins along the eastern margin of the Gulf and may
expand across the basin [Thunell, 1998], acting to fuel high primary productivity. In
summer the northwesterly winds diminish and reverse, producing weak southerly winds
[Douglas et al., 2007]. The slackening of winds causes upwelling to relax and warm
Equatorial Pacific surface water is able to penetrate into the Gulf [Thunell, 1998]. In
summer and early fall (April to October) SST exceeds 29 °C due to increased solar
11
insolation, diminished upwelling, and the intrusion of warm Equatorial water. By the
middle of summer a thick layer (~150 m) of warm (>28 °C) water covers the central and
southern Gulf, creating a deep thermocline [Douglas et al., 2007]. The water column
becomes highly stratified and without the supply of nutrients from depth, the surface
water becomes depleted above the thermocline and primary productivity is reduced
[Thunell et al., 1996]. In addition, summer is the rainy season, with the northward
location of the ITCZ. Most of the precipitation occurs from July through September
[Calvert, 1966], and mainly falls on the south-eastern side of the Gulf on the Mexican
mainland [Douglas et al., 2007].
3. Material and Methods
The ~63.5 m long giant piston core MD02-2515 was collected from Guaymas
Basin (27° 29.01’ N, 112° 04.46’ W, 881 m water depth) in June 2002 during the second
leg of the MONA (Marges Ouest Nord Américaines) cruise of the RV Marion Dufresne
[Beaufort et al., 2002]. The age model used in this study was developed by Pichevin et al.
[2012] and is also described in McClymont et al. [2012]. Chronology of the section of
core analyzed in this study (top 48 m) is based on 17 accelerator mass spectrometry
(AMS)
14C dates measured on bulk organic matter and two additional measurements on
planktonic foraminifera [Pichevin et al., 2012]. An age-depth diagram is shown in figure
3 for the 17 AMS
14C dates used construct the age model.
The core is laminated for considerable portions of its length and lamination
thickness is variable [Cheshire et al., 2005]. Occasional intervals of non-laminated
sediment occur, some of which have been slightly to heavily bioturbated [Beaufort et al.,
12
2002; Figure 4]. The sediments contain varying amounts of biogenic and terrigenous
material, and range in composition from sand to silty clay to diatom ooze (Figure 4).
Sedimentation rates are very high, ranging from ~22 to 275 cm ka
-1and averaging ~120
cm ka
-1(Figure 4).
13
Figure 3. Age-depth diagram for the 17 AMS
14C dates used to construct the age model
by Pichevin et al. [2012]. Interstadials are shown by shaded horizontal bars and
dinoflagellate cyst zones are separated by dashed lines. Heinrich events and the Younger
Dryas are highlighted in dark grey.
Age kyr BP 10 20 30 15 25 35
1a
1b
1c
1d
2a
2b
2c
3
!"#"$%&%
'()
*
+
,
-.
/
0
1&2%3425675#4
!8
!*
!+
!,
9:
0
20
40
60
Corrected depth
(m)
4014
Figure 4. GISP II δ
18O [Stuiver and Grootes, 2000], % total organic carbon (% TOC)
[Pichevin et al., 2012], % biogenic silica (% BioSi) [Pichevin et al., 2012], magnetic
susceptibility [Cheshire et al., 2005], sedimentation rate, lithology and structure
[Beaufort et al., 2002]. Bold curves are 10 point averages. Interstadials are shown by
shaded horizontal bars and dinoflagellate cyst zones are separated by dashed lines.
Heinrich events and the Younger Dryas are highlighted in dark grey.
Age kyr BP
% TOC
% BioSi
!
18O (% )
GISP2
1a 1b 1c 1d 2a 2b 2c 32.0
2.5
3.0
15
25 35 45
-43 -41 -39 -37 -35 -33
!"#"$%&%'()
*
+
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-.
/
0
1&2%3425675#4!8
!*
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9:
Lithology Silty clayNannofossil silty clay Diatom-nannofossil silty clay Diatom silty clay
Diatom ooze Silty clayey diatom ooze Sand
Shell Shell fragment Fish debris Lamination Slump block or fold Slight bioturbation Heavy bioturbation Pyrite concretion Normal graded bedding Isolated layer
Sand lens or pocket Structure Legend
Lithology Struc
tur
e
10 20 30 15 25 35Magnetic
susceptibility
Sedimentation
rate
0 100 200 300 -4 -2 0 2 4 S.I. units cm ka-1 10 20 30 15 25 3515
3.1 Palynological Sample Preparation and Microscopy
One centimetre thick sediment slices were sampled every ~10 to 20 cm along the
core, corresponding to a sampling resolution of ~90 - 300 yrs. Additional intervals were
analyzed at a higher resolution to better constrain the duration of peaks in the
dinoflagellate cyst record. Each sample represents 4 to 45 years, averaging ~8 years of
accumulation. Recovery of dinoflagellate cysts and other palynomorphs from 286
samples was achieved using a standard palynological processing technique [Pospelova et
al., 2004]. Sediment samples of ~2.5 cm
3were oven dried at 40°C and weighed
analytically. One tablet of exotic marker grain Lycopodium clavatum [Stockmarr, 1971;
Mertens et al., 2009] was added prior to sample treatment in order to determine total
palynomorph concentrations. The samples were treated with room temperature 10 % HCl
to remove carbonates, rinsed with distilled water, sieved through 120 µm mesh and
captured on a 15 µm mesh to remove both coarse and fine fractions. Siliceous material
was digested using room temperature 48-50 % HF for 2-3 days, followed by a second 10
% HCl treatment to remove precipitated fluorosilicates. Finally, the samples were rinsed
with distilled water, sieved, gently sonicated for up to 30 seconds and collected on a 15
µm mesh. One to two drops of the residue was mounted in glycerine jelly between a slide
and cover slip.
All palynomorphs were analyzed using a Nikon Eclipse 80i transmitting light
microscope at 600x and 1000x magnifications. Dinoflagellate cysts were identified
according to the paleontological taxonomy system described in Lentin and Williams
[1993]. Cysts of Polykrikos kofoidii and Polykrikos schwartzii follow the nomenclature of
16
possible, however due to morphological similarities and unfavourable orientations it was
not always possible, and some cyst taxa are grouped together. Brigantedinium spp.
consists of Brigantedinium cariacoense, Brigantedinium simplex, and other round brown
cysts, as archeopyles were not always observed due to unfavourable orientations or
folding. Selenopemphix quanta and cyst of Protoperidinium nudum are grouped together
as these two cyst species show a high degree of morphological similarity. Cyst type A has
been previously identified by studies in the Northeast Pacific [e.g. Radi et al., 2007;
Limoges et al., 2010]. Cyst type L is a spiny brown cyst and has been previously reported
by Price and Pospelova [2011] from Saanich Inlet, British Columbia (Canada). Other
spiny brown cysts of unknown affinity were placed in the spiny brown (SBC) category. A
list of all dinoflagellate cyst taxa recorded in this study and their corresponding biological
affinities is provided in Table 1. Plate pictures can be found on the following pages.
An average of 393 cysts were counted per sample (min. 298, max. 946).
Dinoflagellate cyst accumulation rates (cysts cm
-2yr
-1) were calculated by multiplying
the cyst concentration (cysts g
-1), by the sedimentation rate (cm yr
-1), and dry bulk
density (g cm
-3). Dry bulk density measurements were determined by dividing the dry
sediment weight (g) by the wet volume (cm
3).
17
Cyst species
(paleontological name)
Dinoflagellate theca
(biological name)
AutotrophicAchomosphaera spp. ? Gonyaulax sp. Indet. Bitectodinium spongium unknown
Bitectodinium tepikiense Gonyaulax spinifera Impagidinium spp. Gonyaulax sp. Indet. Impagidinium aculeatum Gonyaulax sp. Indet. Impagidinium strialatum Gonyaulax sp. Indet. Impagidinium paradoxum Gonyaulax sp. Indet. Lingulodinium machaerophorum Lingulodinium polyedra Nematosphaeropsis labyrinthus Gonyaulax spinifera complex Operculodinium centrocarpum
sensu Wall & Dale 1966 Protoceratium reticulatum
Operculodinium aguinawense ?Protoceratium sp. Operculodinium israelianium ?Protoceratium sp. Pyxidinopsis reticulata Gonyaulacaceae undif. Polysphaeridium zoharyi Pyrodinium bahamense
Spiniferites belerius Gonyaulax scrippsae, G. spinifera complex Spiniferites ramosus Gonyaulax scrippsae, G. spinifera complex Spiniferites bentorii Gonyaulax digitalis, G. spinifera complex Spiniferites delicatus Gonyaulax spinifera complex
Spiniferites pachydermus Gonyaulax spinifera complex Spiniferites hyperacanthus Gonyaulax spinifera complex
Spiniferites bulloideus Gonyaulax scrippsae, G. spinifera complex Spiniferites mirabilis Gonyaulax spinifera complex
Spiniferites spp. Gonyaulax complex Spiniferites type 1. Gonyaulax complex Tectadodinium pellitum Gonyaulax spinifera complex Tuberculodinium vancampoae Pyrophacus steinii
--- Pentapharsodinium dalei
Heterotrophic
Dubridinium spp. Diplopsalid group
--- Gymnodinium spp.
--- Polykrikos kofoidii
--- Polykrikos schwartzii
--- Polykrikos cf. kofoidii
Brigantedinium spp. ?Protoperidinium spp. Brigantedinium cariacoense Protoperidinium avellana Brigantedinium simplex Protoperidinium conicoides Echinidinium aculeatum Protoperidinium sp. indet. Echinidinium delicatum Protoperidinium sp. indet. Echinidinium cf. zonneveldiae Protoperidinium sp. indet. Echinidinium granulatum Protoperidinium sp. indet. Echinidinium transparantum Protoperidinium sp. indet. Echinidinium spp. Protoperidinium sp. indet. Lejeunecysta oliva Protoperidinium sp. indet. Lejeunecysta sabrina Protoperidinium sp. indet. Lejeunecysta spp. Protoperidinium sp. indet.
--- Protoperidinium americanum
--- Protoperidinium nudum
--- sensu Wall and Dale 1968 Protoperidinium oblongum
Protoperidinium spp. Protoperidinium spp. indet. Quinquecuspis concreta Protoperidinium leonis Selenopemphix nephroides Protoperidinium sp. indet. Selenopemphix undulata Protoperidinium sp. indet. Selenopemphix quanta Protoperidinium conicum Stelladinium reidii Protoperidinium compressum Trinovantedinium applanatum Protoperidinium pentagonum Trinovantedinium variabile Protoperidinium sp. indet. Votadinium calvum Protoperidinium oblongum Votadinium spinosum Protoperidinium claudicans
Cyst type A unknown
Cyst type F unknown
Cyst type L unknown
Spiny brown cysts ?Protoperidinium sp. indet.
Table 1. Taxonomic citation of dinoflagellate cysts identified in this study. Thecate
equivalents are taken from Head [1996], Zonneveld [1997], Zonneveld and Jurkschat
[1999], Marret and Kim [2009], Matsuoka et al., [2009], and Verleye et al. [2011].
18
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19
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23
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25
3.2 Species Diversity and Multivariate Statistical Analyses
The Shannon-Wiener index, a diversity index, was calculated for each sample as
follows:
where H’ is the Shannon-Wiener index, S is the total number of species (species richness)
and p
iis the relative abundance of species i. This diversity index is advantageous as it
takes into consideration the number of species present, as well as the “evenness” of the
species.
Statistical analyses were performed on dinoflagellate cyst relative abundances
using CANOCO 4.5 for Windows [ter Braak and Smilauer, 2002]. The data were
logarithmically [log(x+1)] transformed to increase the statistical weight of species that
occur in lower abundances, as these species are often characterized by a narrower
ecological affinity. Detrended Correspondence Analysis (DCA) was first used to test the
nature of variability within the dinoflagellate cyst assemblage. The length of the first
gradient in standard deviation units was 1.9, which indicates linear variation. Principal
components analysis (PCA) was performed, which reduces the dimensionality of the
dataset while maintaining the variation.
4. Results
4.1 Dinoflagellate Cyst Relative Abundances, Concentrations and Accumulation
Rates
Diverse, abundant and well preserved dinoflagellate cyst assemblages were
recorded from 286 samples in the upper 48 m of core MD02-2515. The most dominant
26
dinoflagellate cyst taxa found consistently throughout were Brigantedinium spp. (9-84
%). Other important contributors were Operculodinium centrocarpum sensu Wall and
Dale 1966 (0-80 %), Spiniferites pachydermus (0-81 %), S. bentorii (0-54 %),
Dubridinium spp. (0-43 %), Lingulodinium machaerophorum (0-33 %), Quinquecuspis
concreta (0-33 %), cyst of Polykrikos cf. kofoidii (0-30 %), and Echinidinium aculeatum
(0-10 %). A number of peaks are observed throughout the record where one taxon
increases in abundance by ~30-80 % from the preceding samples, and subsequently
declines by a similar magnitude in the following samples. These peaks are almost
exclusively produced by O. centrocarpum, S. pachydermus, and S. bentorii, all of which
are autotrophic taxa (Figure 5).
A total of 62 dinoflagellate taxa were identified (Table 1). The number of species
in each sample ranged from 13 to 33, with an average of 24. The Shannon-Wiener index
varied from 0.84 to 2.49, averaging 1.8 and was lowest from ~36-23 ka, and was highest
in the Holocene and at the bottom of the core ~38-39 ka (Figure 6). Dinoflagellate cyst
concentrations vary by two orders of magnitude, from ~3,500 cysts g
-1to ~183,000 cysts
g
-1, averaging ~18,500 cysts g
-1. Large fluctuations are also apparent, particularly in cysts
of autotrophic taxa in sediments younger than ~22.8 ka (Figure 5). In general
concentrations of heterotrophic (H) taxa are much greater than concentrations of
autotrophic (A) taxa, and is reflected in the H/A ratio (Figure 5). Heinrich event 1 is one
notable exception to this trend.
Total dinoflagellate cyst accumulation rates vary from ~36 cysts cm
-2yr
-1to 8,150
cysts cm
-2yr
-1, averaging ~1,580 cysts cm
-2yr
-1. Cyst accumulation rates are highest from
22.3 to 16.9 ka, roughly corresponding to the LGM and HE1. During this interval cyst
27
accumulation rates show considerable fluctuations and a general increasing trend (Figure
6). The high cyst accumulation rate during this period is predominantly driven by an
increase in sedimentation rate from ~170 cm ka
-1to ~280 cm ka
-1as well as high
concentrations of cysts of heterotrophic taxa. In addition, this interval shows many abrupt
peaks in the record, which are almost exclusively the result of significant increases in the
production of autotrophic taxa. At ~16.9 ka when the sedimentation rate drops by ~50 %,
the total cyst accumulation rate declines significantly, followed by a slow decrease before
levelling out at ~15.1 ka (Figure 6). Although only relative abundances of individual
dinoflagellate cyst taxa are displayed in figure 5, cyst concentrations and accumulation
rates show similar trends.
28
Fig
ure
5.
Relative abundances (%) of selected
dinoflagellate cyst taxa. Dinoflagellate cysts species that characterize particular
zones are highlighted in color. Interstadials are shown by shaded horizontal bars and dinoflagellate cyst zones are separated by
dashed lines. Heinrich events and the Younger Dryas are highlighted in dark grey.
1a 1b 1c 1d 2a 2b 2c 3 10 20 30 Age kyr BP 0 10 20 30 Lingulodinium machaerophorum 0 10 Nematosphaeropis labyrinthus 0 10 20 30 40 50 Operculodinium centrocarpum 0 10 20 Spiniferites bentorii Spiniferites pachydermus Tuberculodinium vancampoae Brigantedinium spp. Protoperidinium spp. Dubrinidium spp. Echinidinium aculeatum Quinquecuspis concreta Cyst of Polykrikos schwartzii Cyst of Polykrikos cf. kofoidii Stelladinium reidii Cyst type A SBC Cyst type L 0 10 20 30 40 81 60 78 72 36 44 53 54 31 80 56 57 74 69 0 10 20 30 40 0 10 20 0 10 20 0 20 40 60 0 10 0 10 0 10 0 10 0 5 0 5 0 5 0 5 !"#"$%&% '() * + , - . / 0 1&2%3425675#4 !8 !* !+ !, 9: 15 25 35 % Zones
29
4.2 Statistical Analyses and Dinoflagellate Cyst Zones
Principal components analysis performed on logarithmically transformed relative
abundance data yields four axes explaining 21.4 %, 11.8 %, 9.6 % and 8.0 % of the
variance respectively, for a total of 50.7 % (Figure 6). It provides insight into similarities
and differences in the dinoflagellate cyst assemblages recorded throughout the core.
Figure 7, a PCA biplot, shows the ordination of samples and species along the two most
dominant ordination axes, PCA1 and PCA2. Most cysts of autotrophic species are
ordinated on the positive side of PCA1.
Based on sample scores from PCA axes 1, 2, 3, and 4, and visual inspection of the
dinoflagellate cyst abundances, three major dinoflagellate cyst zones were established
with seven subzones. Zone 1 (40 - 22.8 ka) is characterized by negative PCA1 and PCA2
values, whereas zone 2 (22.8 - 11.1 ka) is characterized by mostly positive PCA1 and/or
PCA 2 values (Figure 6). Zone 3 has the highest positive PCA 2 values in the record.
Division of the subzones also involved PCA3 and PCA4 (Figure 6). Although all zones
are dominated by Brigantedinium spp., zone 2 is characterized by the consistent presence
and often high and fluctuating values of Operculodinium centrocarpum (0.5-80 %,
average 10.4 %) (Figure 5). O. centrocarpum in zone 1 never constitutes more than 5 %
of the total assemblage. Samples in dinoflagellate cyst zones 1 and 3 predominately
cluster together compared to samples found in zone 2, which show greater variation
(Figure 7). Greater dissimilarities in zone 1 are however observed in PCA3 and PCA4
(Figure 6). Characteristic species of each dinoflagellate cyst subzone are highlighted in
color in Figure 5.
30
Figure
6
. Sedimentation rate; concentrations and fluxes for total, autotrophic and heterotrophic taxa; ratio of heterotrophic (H) to
autotrophic (A) taxa, and A/H; Shannon
-Wiener index with colored vertical lines highlighting distinct changes; and sample scores for
PCA axes 1
-4, where different colors highlight changes between zones. Interstadials are shown by shaded horizontal bars and
dinoflagellate cyst zones are separat
ed by dashed lines. Heinrich events and the Younger Dryas are highlighted in dark grey.
Age kyr BP 18.3 10.3 15.5 8.8
A/H
H/A
Shannon-W
iener
inde
x
-1
0
2
-2
-1
0
1
2
-1
0
1
2
-1
0
1
2
10 15 20 25 30 35Total
dino
flagella
te
cy
sts
Aut
otr
ophic
taxa
Het
er
otr
ophic
taxa
1a 1b 1c 1d 2a 2b 2c 3 !"#"$%&% '() * + , - . / 0 1&2%3425675#4 !8 !* !+ !, 9: Conc en tr ations (shaded g rey) x 10 4 cy sts g -1 F lux es (black) x 10 3 cy sts cm -2 yr -1 0 2 4 6 0 2 4 6 0 2 4 6 0 2 4 0.6 1.1 1.6 2.1 2.6 0 2 4 6 8 0 2 4 6 0 2 4 0 20 40 PC A1 (21.4 %) PC A2 (11.8 %) PC A3 (9.6 %) PC A4 (8.0 %)1
cm k yr -1 0 100 200Sedimen
ta
tion
ra
te
31
Figure 7. Ordination diagram generated by principal components analysis (PCA)
showing dinoflagellate cyst taxa (black arrows) and ordination of samples (colored dots
and triangles). Abbreviations: Bspp, Brigantedinium spp; Proto, Protoperidinium spp;
Dubr, Dubrinidium spp.; CystA, Cyst type A; SBC, spiny brown cysts and Echinidinium
species; CystL, Cyst type L; Psch, cyst of Polykrikos schwartzii; Pkof, cyst of Polykrikos
kofoidii; Pcfk, cyst of Polykrikos cf. kofoidii; Ocent, Operculodinium centrocarpum
sensu Wall and Dale 1966; Sben, Spiniferites bentorii; Spac, Spiniferites pachydermus;
Nlab, Nematosphaeropsis labyrinthus; Lmac, Lingulodinium machaerophorum; Eacu,
Echinidinium aculeatum; Tvan, Tuberculodinium vancampoae; Stel, Stelladinium reidii;
Qcon, Quinquecuspis contreta; Operculodinium aguinawense; Pdal, cyst of
Pentapharsodinium dalei; Pzoh, Polysphaeridium zoharyi; Sram, includes Spiniferites
ramosus and Spiniferites bulloideus; Ssp1, Spiniferites type 1; Sspp, Spiniferites spp.;
Smir, Spiniferites mirablis; Squa, includes Selenopemphix quanta and cysts of
Protoperidinum nudum; Sneph, Selenopemphix nephroides; Sund, Selenopemphix
undulata; Imap; Impagidinium spp. Eigenvalues are shown at the bottom of the figure.
1.0
-1.0
1.0
DZ-1a DZ-1b DZ-1c DZ-1d DZ-2a DZ-2b DZ-2c DZ-3Legend
Bspon
Imag
Lmac
Nlab
Ocent
Oagu
Pdal
Pzoh
Sram
Sben
Smir
Spach
Ssp1
Sspp
Tvan
Brig
Prot
Pam
Dubr
Eacu
Qcon
Psch
Pkoif
Pcfkoif
Sund
Sneph
Squan
Stell
Cysta
SBC
TypeL
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