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Humblet, M. and Iryu, Y. 2014: Pleistocene coral assemblages on Irabu-jima,

South Ryukyu Islands, Japan. Paleontological Research,

doi: 10.2517/2014PR020.

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doi:10.2517/2017PR001

Radiolarian biostratigraphy from middle Miocene to late Pleistocene

in the Japan Sea

SHIN-ICHI KAMIKURI 1, TAKUYA ITAKI 2, ISAO MOTOYAMA 3 AND KENJI M.

MATSUZAKI 4

1Faculty of Education, Ibaraki University, 2-1-1 Bunkyo, Mito, Ibaraki 310-8512, Japan

([email protected]） 2AIST, Geological Survey of Japan, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8567, Japan 3Department of Earth and Environmental Sciences, Yamagata University, 1-4-12

Kojirakawa-machi, Yamagata 990-8560, Japan

4Department of Earth and Planetary Science, Graduate School of Science, the

University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan

Abstract. In the Integrated Ocean Drilling Program (IODP) Exp. 346, sampling by

drilling was conducted at seven sites (U1422–U1427 and U1430) in the Japan Sea.

Radiolarians in moderately well preserved states were found in most samples

throughout the sequence in varying abundance. Forty-one radiolarian datum

events were identified in this study, and the radiolarian zonation that best divides

the middle Miocene to Pleistocene sequences with updated ages of radiolarian

datum events (estimates based on the geomagnetic polarity time scale (GTS) 2012)

was applied to the sedimentary sequences in the Japan Sea. Here, four new

radiolarian zones are proposed for the Quaternary of the Japan Sea, and one zone

is slightly revised to adjust for differences among other zones. The sequences

collected at the sites extended from the Pleistocene Ceratospyris borealis Zone to

progressively deeper zones as follows: Site U1427, four zones to the Pleistocene

Schizodiscus japonicus; Site U1422, six zones to the late Pliocene Hexacontium

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parviakitaense Zone; Sites U1423, U1424 and U1426, eight zones to the early

Pliocene Larcopyle pylomaticus Zone; and Sites U1425 and U1430, fourteen zones

to the middle Miocene Eucyrtidium inflatum Zone. The absence or extremely rare

occurrence of Stylatractus universus and E. matuyamai indicates that S. universus

lived in the deep water of the northwestern Pacific and had not been able to

migrate into the Japan Sea across the Tsugaru Strait since the Pliocene.

Key words: IODP Exp. 346, Japan Sea, middle Miocene to Quaternary,

radiolarian zonation, sedimentation rate

Introduction

The recently conducted Integrated Ocean Drilling Program (IODP) Expedition 346

recovered sedimentary sequences with a total length of 6135.3 m from cores taken from

the sea floor at seven sites in the Japan Sea (Tada et al., 2015). The sediment samples

offer an ideal record for understanding the atmosphere-ocean linkage during the late

Neogene and Quaternary that are related to the East Asian monsoonal system. The

drilling sites were selected to achieve a depth transect of cores off the Japanese Islands

in the Japan Sea in order to collect information on depth-dependent sedimentation,

ocean chemistry, and marine organisms from the middle Miocene to Quaternary.

Radiolarians are planktonic unicellular Protoctista, and inhabit shallow-to-deep

waters at depths as deep as 5,000 m in the modern ocean (Reshetnyak, 1955;

Petrushevskaya, 1971). The opal skeletons are well preserved in the sea-floor sediments

and have been widely used as a proxy to reconstruct paleoceanographic history and to

determine the geological age to a resolution of 1,000–10,000 years. The main objectives

of this study are to establish radiolarian biostratigraphy for more precise dating and to

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establish correlations among sedimentary sequences drilled at IODP Sites

U1422–U1427 and U1430 in the Japan Sea.

Material and methods

Techniques

In this study, a total of 559 core samples were collected for biostratigraphic analysis

from IODP Exp. 346 Sites U1422–U1427 and U1430 in the Japan Sea (Figure 1). The

lithology of these cores is described in detail by Tada et al. (2015). Here locality and

lithology are briefly described. Sample preparation was conducted following the

methods described in Itaki (2001a). All samples were freeze-dried, weighed, and then

treated with 10% H2O2 solution to remove organic matter and 10% HCl to remove

calcium carbonate. If the samples contained large quantities of lithologenic grains, opal

particles were extracted from the residues using the elutriation method (Itaki, 2003).

The residues were then wet sieved through a 45-µm mesh, dried on a slide, mounted

with Norland optical adhesive, and covered with a 22 mm × 40 mm cover glass. The

adhesive was solidified by placing the slide under a UV light (300–400 nm) for

approximately 15 minutes. Original data for Sites U1424, U1426 and U1427 were

reported by Tada et al. (2015).

Abbreviations for radiolarian abundances in a slide are A, abundant (>10,000

specimens per slide); C, common (2,000–10,000 specimens per slide); F, few

(500–2,000 specimens per slide); R, rare (50–500 specimens per slide); VR, very rare

(<50 specimens per slide); and B, barren (0 specimens per slide).

The relative abundance of individual radiolarian species is designated as A,

abundant (≥16% of the radiolarian assemblage); C, common (4–16% of the radiolarian

assemblage); F, few (1–4% of the radiolarian assemblage); R, rare (0.2–1% of the

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radiolarian assemblage); and P, present (<0.2%).

Preservation of the radiolarian specimens was recorded as G (good), only minor

fragmentation; M (moderate), obvious fragmentation but identification of species not

impaired; and P (poor), individual taxa exhibited considerable fragmentation, and

identification of some species was not possible.

Radiolarian zonation

Radiolarian zonation was first introduced by Nakaseko and Sugano (1973) based on

samples from the Japan Sea (Figure 2). Four assemblage zones extending from late

early Miocene to Pliocene were based on earlier studies of sediment samples collected

from onshore Japan by Nakaseko and co-workers (Nakaseko, 1954, 1960; Nakaseko et

al., 1965, 1972; Sugano and Nakaseko, 1968, 1971). Later, Funayama (1988)

distinguished four interval zones including two new zones and two new interval

subzones from the late early Miocene to early late Miocene in the Noto Peninsula

(central Japan). Ling (1975, 1992) and Alexandrovich (1992) reported occurrences of

radiolarians in Deep Sea Drilling Project (DSDP) Leg 31 and Ocean Drilling Program

(ODP) Legs 127 and 128 in the Japan Sea, but they proposed no radiolarian zonation for

the late Miocene to Quaternary. Tochilina (1985) and Vasilenko (2015) distinguished

four new assemblages from the late Miocene to the late Pliocene in the Japan Sea,

respectively. Motoyama (1996) defined eight radiolarian zones, including seven new

zones, for an interval between the upper Miocene and the lower Pleistocene based on

the DSDP Leg 31 Site 302 sequence (40°20.13′N and 136°54.01′E; water depth, 2399

m) in the Japan Sea. Itaki (2001b) recognized four new assemblage zones during the last

30 kyr based on piston cores taken off the Oga Peninsula in the Japan Sea. In this study,

the radiolarian zonation for the Japan Sea follows mainly Funayama (1988), Motoyama

(1996) and Itaki (2001b).

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Radiolarian datum levels

Not all radiolarian species identified in this study were used (Table 1). Most of the

radiolarian species selected for their stratigraphic usefulness were previously described

in Japan Sea and North Pacific sediments by other investigators (Foreman, 1973, 1975;

Kling, 1973; Ling, 1973; Sakai, 1980; Weaver et al., 1981; Wolfart, 1981; Popova,

1989; Spencer-Cervato et al., 1993; Vitukhin, 1993; Bak et al., 2012). In the subarctic

North Pacific, over 60 radiolarian datum levels have been directly tied to the

paleomagnetostratigraphy since the early Miocene (Morley and Nigrini, 1995; Shilov,

1995; Kamikuri et al., 2007; Kamikuri, 2010). In the temperate North Pacific, only

Pliocene and Pleistocene datum levels were directly tied to the

paleomagnetostratigraphy (Hays, 1970; Reynolds, 1980; Morley, 1985; Motoyama,

1996; Kamikuri et al., 2004). Recently, 17 radiolarian bioevents from the middle to late

Pleistocene were calibrated to the benthic foraminiferal oxygen isotope curves in the

temperate Northwest Pacific (Matsuzaki et al., 2014). In the Sea of Okhotsk, the late

Quaternary datum levels were precisely calibrated to the oxygen isotope curves

measured in the benthic foraminifera (Matul et al., 2002, 2009). In the Bering Sea,

radiolarian datum levels since the late Pliocene were tied to the

paleomagnetostratigraphy and the cyclostratigraphy of oxygen isotopes and Si/Al ratios

(Ikenoue et al., 2016). Only late Quaternary datum levels in the Japan Sea, on the other

hand, were indirectly correlated to the oxygen isotope stratigraphy (Itaki et al., 2007).

In this study, the correlation between magneto-oxygen isotope stratigraphy and

radiolarian datum levels mainly follows Matul et al. (2002), Kamikuri et al. (2004,

2007), Itaki et al. (2007), Kamikuri (2010), and Ikenoue et al. (2016) (Table 1). The

ages of the biohorizons used in this study are updated based on the geologic time-scale

(GTS) of Ogg (2012) by extrapolation of each horizon within each magnetic chron.

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Radiolarian datum levels and zonation in the Japan Sea

A summary of the radiolarian datum levels identified in this study is presented in

Table 1. The following abbreviations are used in this study to express events; FO, first

occurrence; LO, last occurrence; RI, rapid increase; RD, rapid decrease. The concept of

evolutionary transition (ET) follows that of Sanfilippo and Nigrini (1998).

The Japan Sea has developed a unique radiolarian fauna, especially since the late

Pliocene Epoch when the sea became more isolated from the Pacific Ocean due to

enhanced uplift of the Japanese archipelago (Kamikuri and Motoyama, 2007; Itaki,

2016). This makes it difficult to apply radiolarian zones established for the North

Pacific to the marginal sea. Thus, we here propose a local radiolarian zonal scheme for

the Quaternary Period in the Japan Sea.

The sedimentary sequences were divided into six zones from the Ceratospyris

borealis Zone to the Hexacontium parviakitaense Zone at Site U1422, eight zones from

the C. borealis Zone to the Larcopyle pylomaticus Zone at Sites U1423, U1424 and

U1426, fourteen zones from the C. borealis Zone to the Eucyrtidium inflatum Zone at

Sites U1425 and U1430, and four zones from the C. borealis to the Schizodiscus

japonicus Zone at Site U1427 (Figures 2–4, Table 1).

Ceratospyris borealis Zone (Itaki, 2001b; emend. herein)

Category.—Interval zone.

Definition.—Interval between the RD of Ceratospyris borealis (top) and the LO of

Lychnocanoma sakaii (base).

Age.—Late Pleistocene (54–15 ka).

Remarks.—Itaki (2001b) defined four assemblage zones: Larcopyle buetschlii Zone

(0–10.5 ka), Stylochlamydium venustum Zone (10.5–13 ka), Spongodiscus resurgens

Zone (13–15 ka), and Ceratospyris borealis Zone (15–28 ka). The C. borealis Zone was

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defined by abundant occurrence of C. borealis, but the lower limit of this zone was not

recognized (Itaki, 2001b). In the present study, the C. borealis Zone is employed as an

interval zone, and the LO of L. sakaii is taken as the lower limit of this zone.

Lychnocanoma sakaii Zone (herein)


Definition.—Interval from the LO of Lychnocanoma sakaii (top) to the LO of

Amphimelissa setosa (base).

Age.—Late Pleistocene (0.085–0.054 Ma).

Remarks.—It is difficult to determine the LO of Amphimelissa setosa at Site 1424

because the species has a very sparse and sporadic occurrence.

Amphimelissa setosa Zone (herein)


Definition.—Interval from the LO of Amphimelissa setosa (top) to the LO of

Schizodiscus japonicus (base).

Age.—Middle to Late Pleistocene (0.29–0.085 Ma).

Remarks.—Hays (1970) originally defined the Stylatractus universus Zone as an

interval zone from the LO of S. universus (top) to the LO of Eucyrtidium matuyamai

(base) for the subarctic North Pacific. Later, Ikenoue et al. (2016) changed the zonal

name from S. universus Zone to Amphimelissa setosa Zone because A. setosa was the

most abundant and characteristic species during the late Quaternary in the southern

Bering Sea. In the North Pacific, there are two radiolarian zones with the same

definition. ISSC (1994) clarified the nomenclature rules for zones, stating that the taxon

for which the zone is named does not have to be a common taxon within the zone or be

a particularly good guide-fossil among the members of the assemblage. Following this

rule, different names should not be assigned to the same biostratigraphic unit, and the A.

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setosa Zone of Ikenoue et al. (2016) is not accepted. Because the S. universus Zone has

been duly proposed as an unequivocal designation of the zonal limits by Hays (1970),

we follow the definition and define the A. setosa Zone as a new zone here.

Schizodiscus japonicus Zone (herein)


Definition.—Interval from the LO of Schizodiscus japonicus (top) to the LO of

Axoprunum acquilonium (base).

Age.—Early to Middle Pleistocene (1.7–0.29 Ma).

Secondary events.—FO of Amphimelissa setosa and very short-ranging of

Eucyrtidium matuyamai.

Remarks.—In this study, Eucyrtidium matuyamai was not observed at Sites U1423,

U1425, U1427 and U1430, likely due to low stratigraphic resolution.

Hexacontium minerva Zone (herein)


Definition.—Interval from the LO Axoprunum acquilonium (top) to the ET from

Cycladophora sphaeris to C. davisiana (base).

Age.—Early Pleistocene (2.6–1.7 Ma).

Secondary events.—LO of Cycladophora sphaeris.

Remarks.— This zone approximately correlates with the Spongodiscus osculosus

Zone of Tochilina (1985) and the Cycladophora davisiana Assemblage of Vasilenko

(2015).

Hexacontium parviakitaense Zone (Kamikuri, in press; emend. herein)


Definition.—Interval between the ET from Cycladophora sphaeris to C. davisiana

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(top) and the LO of Dictyophimus bullatus (base).

Age.—Early to late Pliocene (3.9–2.6 Ma).

Secondary events.—FO and LO of Hexacontium parviakitaense and FO of

Cycladophora davisiana.

Remarks.—Motoyama (1996) defined the Cycladophora sphaeris Zone (=

Cycladophora sakaii Zone in the original paper) as an interval from the FO of

Eucyrtidium matuyamai (top) to the LO of Dictyophimus bullatus (base). However, E.

matuyamai shows sporadic occurrence, probably due to a very short biostratigraphic

range in the Japan Sea, making it difficult to recognize the FO and LO in Sites U1423,

U1425, U1427 and U1430. Hence, the C. sphaeris Zone was not assigned in the Japan

Sea.

The Cycladophora sphaeris Zone was subdivided into two subzones in the North

Pacific (Kamikuri, in press): Hexacontium dionysus and H. parviakitaense Subzones. In

this study, we use the latter subzone as a zone between the H. minerva Zone and

Dictyophimus bullatus Zone in the Japan Sea. Kamikuri (in press) defined the first

consistent occurrence of Cycladophora davisiana as the upper limit of the H.

parviakitaense Subzone (H. parviakitaense Zone in the present paper). As Kamikuri (in

press) already mentioned, the ET from Cycladophora sphaeris to C. davisiana is used

for the upper limit of this zone in the Japan Sea. The H. dionysus Subzone correlates the

lower part of the H. minerva Zone.

The LO of Hexacontium parviakitaense closely approximates to the top of this zone,

and the FO is also a good marker for the base of this zone (Kamikuri, 2010).

Dictyophimus bullatus Zone (Motoyama, 1996; rename. Kamikuri et al., 2004)

Category.—Taxon range zone.

Definition.—Taxon range of Dictyophimus bullatus.

Age.—Early Pliocene (4.4–3.9 Ma).

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Secondary events.—RD of Siphocampe arachnea group.

Remarks.—The FO and LO of Dictyophimus bullatus was not recognized at Sites

1424 and 1426, due to very sparse and sporadic occurrence.

Larcopyle pylomaticus Zone (Motoyama, 1996)


Definition.—Interval from the FO of Dictyophimus bullatus (top) to the FO of

Larcopyle pylomaticus (base).

Age.—Late Miocene to early Pliocene (5.4–4.4 Ma).

Remarks.—This zone is divided into the next two subzones. Kamikuri (in press) used

the LO of L. redondoensis as a subzone marker (not zone), because of its usefulness as a

biostratigraphic marker in latitudes higher than 38°N of the North Pacific.

Lamprocyclas hannai Subzone (Kamikuri, in press)


Definition.—Interval from the FO of Dictyophimus bullatus (top) to the LO of

Lipmanella redondoensis (base).

Age.—Early Pliocene (4.9–4.4 Ma).

Secondary events.—RI of Siphocampe arachnea group.

Remarks.—The RI of Siphocampe arachnea group is a good marker for the middle

part of this subzone (Kamikuri et al., 2004).

Lithelius klingi Subzone (Kamikuri, in press)


Definition.—Interval from the LO of Lipmanella redondoensis (top) to the FO of

Larcopyle pylomaticus (base).

Age.—Late Miocene to early Pliocene (5.4–4.9 Ma).

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Remarks.—The coinciding recognition of the LO of Lipmanella redondoensis and the

FO of Larcopyle pylomaticus near 79.0 m at Site U1430 (Table 1, Figure 3) indicates

that the Lithelius klingi Subzone is absent in the studied core.

Axoprunum acquilonium Zone (Shilov, 1995; emend. Motoyama, 1996)


Definition.—Interval from the FO of Larcopyle pylomaticus (top) to the LO of

Lychnocanoma parallelipes (base).

Age.—Late Miocene (6.1–5.4 Ma).

Secondary events.—RD of Lithelius barbatus.

Remarks.—The FO of Larcopyle pylomaticus and the LO of Lychnocanoma

parallelipes are located at the same level near 79.0 m at Site U1430 (Table 1, Figure 3).

Hence, the Axoprunum acquilonium Zone is absent in the studied core.

Lithelius barbatus Zone (Motoyama, 1996)


Definition.—Interval from the LO of Lychnocanoma parallelipes (top) to the RI of

Lithelius barbatus (base).


Secondary events.—FO of Axoprunum acquilonium.

Remarks.—The FO of Axoprunum acquilonium coincides with the base of this zone

and can be used as an additional marker for recognizing the base of this zone (Kamikuri

et al., 2004). The Lithelius barbatus Zone is not designated at Site U1430 because no

peak event of L. barbatus is found in this studied core (Table 1, Figure 3).

Lychnocanoma parallelipes Zone (Motoyama, 1996)


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Definition.—Interval from the RI of Lithelius barbatus (top) to the FO of

Lychnocanoma parallelipes (base).


Secondary events.—LO of Cycladophora nakasekoi.

Remarks.—The LO of Cycladophora nakasekoi is a good marker horizon for the

base of this zone (Motoyama, 1996; Kamikuri et al., 2004).

Cycladophora funakawai Zone (Motoyama, 1996; emend. Kamikuri, in press)


Definition.—Interval from the FO of Lychnocanoma parallelipes (top) to the LO of

L. magnacornuta (base).


Secondary events.—FO of Cycladophora sphaeris.

Remarks.—The FO of Cycladophora sphaeris is a useful biohorizon for the middle

part of this zone. This zone approximately correlates the Spurioclathrocyclas urymensis

Assemblage of Vasilenko (2015). However S. urymensis was not encountered in this

study.

Lychnocanoma magnacornuta Zone (Funayama, 1988)

Category.—Taxon range zone.

Definition.—Taxon range of Lychnocanoma magnacornuta (base).

Age.—Middle to late Miocene (11.8–9.1 Ma).

Remarks.—This zone corresponds to the Lychnocanoma nipponica magnacorunuta

Assemblage of Vasilenko (2015) and the lower part of the Lychnocanium nipponicum

Zone of Tochilina (1985). The L. magnacorunuta Taxon range zone is divided into the

following two subzones.

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Collosphaera reynoldsi Subzone (Kamikuri, in press)

Category.—Interval subzone.

Definition.—Interval from the LO of Lychnocanoma magnacornuta (top) to the LO

of Cyrtocapsella japonica (base).


Secondary events.—FO of Cycladophora nakasekoi.

Remarks.—The FO of Cycladophora nakasekoi can be used as an additional marker

horizon for recognizing the base of this zone (Motoyama and Maruyama, 1998;

Kamikuri et al., 2004).

Cyrtocapsella japonica Subzone (Nakaseko and Sugano, 1972; emend. Kamikuri, in

press)


Definition.—Interval from the LO of Cyrtocapsella japonica (top) to the FO of

Lychnocanoma magnacornuta (base).

Age.—Middle to late Miocene (11.8–10.0 Ma).

Secondary events.—FO and LO of Dendrospyris uruyaensis.

Remarks.—This subzone was not encountered at Site U1425, probably due to low

stratigraphic resolution.

Eucyrtidium inflatum Zone (Reynolds, 1980; emend. Funayama, 1988)


Definition.—Interval from the FO of Lychnocanoma magnacornuta (top) to the FO

of Eucyrtidium inflatum (base).

Age.—Middle Miocene (15.0–11.8 Ma).

Remarks.—This zone is divided into the following two subzones.

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Eucyrtidium inflatum b Subzone (Funayama, 1988)


Definition.—Interval from the FO of Lychnocanoma magnacornuta (top) to the RD

of Cyrtocapsella tetrapera (base).


Secondary events.—LOs of Eucyrtidium inflatum, Lithopera renzae and

Calocycletta motoyamai.

Remarks.—The LO of Calocycletta motoyamai and the LO of Eucyrtidium inflatum

are good markers for the top of this zone (Kamikuri et al., 2007; Kamikuri, 2010).

Eucyrtidium inflatum a Subzone (Funayama, 1988)


Definition.—Interval from the RD of Cyrtocapsella tetrapera (base) to the FO of

Eucyrtidium inflatum (base).


Secondary events.—FO of Calocycletta motoyamai and LO of these species:

Dendrospyris sakaii, Lipmanella hister, Stylosphaera magnaporulosa and Eucyrtidium

asanoi.

Remarks.—The RD of Cyrtocapsella tetrapera, FO of Calocycletta motoyamai, and

LO of Stylosphaera magnaporulosa occur at the same level between Site

1430A-29X-CC and 30X-CC. The LOs of Eucyrtidium asanoi, Dendrospyris sakaii and

Lipmanella hister are also found at the same horizon between Site 1430A-30X-CC and

31X-CC (Table 1, Figure 3). This suggests that the interval between 12.7 and 14.9 Ma

was recorded in the short sedimentary sequence from Site 1430A-29X-CC to 31X-CC

(264.43–270.13 m). The FO of Calocycletta motoyamai is a useful marker for the upper

part of this subzone (Kamikuri, 2010).

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Discussion

Motoyama (1996) presented the stratigraphic distribution of radiolarians at DSDP

Site 302 in central Japan in order to establish radiolarian zonation and reported that the

Quaternary radiolarian zones proposed by Hays (1970) and Foreman (1975) could not

be applied to DSDP Site 302.

The Quaternary radiolarian zones in the North Pacific were first developed by Hays

(1970). He defined four radiolarian zones from the Botryostrobus aquilonaris Zone

(=Eucyrtidium tumidulum in the original paper) to the Lamprocyrtis heteroporos Zone.

Later, Foreman (1975) revised Hays’s Eucyrtidium matuyamai Zone. The four zones

were distinguished by LOs of Stylatractus universus and E. matuyamai, and FO of E.

matuyamai. The zonation has been accepted as a standard zonal scheme for the middle

to high latitudes of the North Pacific (Kling, 1973; Sakai, 1980; Reynolds, 1980;

Weaver et al., 1981; Wolfart, 1981; Morley, 1985; Motoyama and Maruyama, 1998;

Kamikuri et al., 2007).

Stylatractus universus has been reported from the Southern Ocean (Hays, 1965),

North Pacific (Spencere-Cervato et al., 1993, Morley and Nigrini, 1995; Shilov, 1995;

Motoyama, 1996; Kamikuri et al., 2004), equatorial Pacific (Johnson and Knoll, 1974;

Moore, 1995; Kamikuri et al., 2009) and equatorial Atlantic and Indian oceans (Nigrini,

1967; Hays and Shackleton, 1976; Caulet et al., 1993). Based on these observations,

Hays and Shackleton (1976) suggested that S. universus effectively has a global

geographic distribution. They also showed that the LO of S. universus is globally

synchronous through comparison of the datum with oxygen isotope records over

widespread high- and low-latitude deep-sea sediments and that the isotopic transition is

between Stages 11 and 12 globally. Hays (1970) and Morley and Nigrini (1995)

suggested that the LO of S. universus is synchronous throughout the North Pacific. The

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cause of extinction for this species is unclear.

Hays (1970) documented the evolutionary history of Eucyrtidium matuyamai

during the early Pleistocene in the subarctic North Pacific. It evolved from Eucyrtidium

calvertense, which has a relatively small shell and a geographic distribution ranging

from the Bering Sea to 34°N. The LO of E. matuyamai within the Chron C1r.1n

(Jaramillo event) is a very good marker horizon for biostratigraphic correlation of the

middle- to high-latitude North Pacific (Hays, 1970; Kling, 1973; Foreman, 1975;

Kellogg and Hays, 1975; Reynolds, 1980; Sakai, 1980; Wolfart, 1981; Weaver et al.,

1981; Morley, 1985; Spencer-Cervato et al., 1993; Morley and Nigrini, 1995;

Motoyama, 1996; Kamikuri et al., 2004, 2007). The FO of E. matuyamai occurred near

the base of Chron C2n (Olduvai event) and is also synchronous throughout the North

Pacific.

In IODP Exp. 346, cores were taken at seven sites covering a wide latitudinal range

of the Japan Sea (Figure 1). In the cores recovered during this expedition, Stylatractus

universus was completely absent after the Pliocene (Appendix). In addition,

Eucyrtidium matuyamai occurred in only a single sample from each of Sites U1422,

U1424 and U1426. Hence, three bioevents (LOs of S. universus and E. matuyamai, and

FO of E. matuyamai) were either missing or had different ranges between the Japan Sea

and the open ocean. Although the LO of S. universus and E. matuyamai and FO of E.

matuyamai, which together define the Quaternary radiolarian zones for the subarctic

North Pacific, appear to be reliable synchronous biostratigraphic events throughout the

North Pacific, the absence or extremely rare occurrence of these species in this study

indicate that the usefulness of these markers are limited in the Japan Sea. The

occurrences were probably because S. universus and E. matuyamai are basically

intermediate to deep waters in vertical distribution, as mentioned below.

The modern Japan Sea is a semi-enclosed marginal sea in the Northwest Pacific and

is connected to other seas by four narrow and shallow straits with a maximum sill depth

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of 130 m. The Japan Sea opened in the early Miocene, and the position of straits has had

an influence on paleoceanographic changes, such as surface- and deep-water circulation

in the Japan Sea, since the Early Miocene (Jolivet and Tamaki, 1992; Tada, 1994). The

final restriction of the deeper water (probably intermediate water) connection between

the Japan Sea and Pacific is accompanied by uplift of the strait (paleo-Tsugaru Strait) in

northern Japan and an eustatic sea level drop during the late Pliocene (Tada, 1994;

Kamikuri and Motoyama, 2007; Itaki, 2016). Deeper-dwelling taxa, including

Cornutella profunda and Peripyramis circumtexta, may not have moved from the North

Pacific to the Japan Sea since the late Pliocene. Hence, the absence or extremely rare

occurrence of zonal markers Stylatractus universus and Eucyrtidium matuyamai likely

indicates that they inhabited deeper waters. Stylatractus universus was recognized at

ODP Sites 438 (40°37.79′N and 143°14.15′E; water depth, 1558 m) and 1150 (39°11′N

and 143°20′E; water depth, 2681 m) off the east coast of Honshu Island (Motoyama,

1996; Kamikuri et al., 2004) but did not occur at JAMSTEC Hole 902-C9001C

(41°10′N and 142°12′E; water depth, 1180 m) near the Tsugaru Strait (Matsuzaki et al.,

2014). Stylatractus universus appears to have inhabited deep water below 1200 m in the

northwestern Pacific and has not been able to migrate into the Japan Sea across the

Tsugaru Strait since the Pliocene. On the other hand, in the Bering Sea, which is the

northernmost marginal sea of the North Pacific, S. universus and E. matuyamai were

identified from the Late Quaternary sediment (Ikenoue et al., 2016), and this

distribution was likely made possible by the several deep straits, such as Kamchatka

Strait (maximum water depth, 4420 m), that connect this marginal sea to the North

Pacific.

Matul et al. (2002) identified four radiolarian datum events in the late Quaternary

sediment from the Sea of Okhotsk that they suggest are approximately synchronous in

comparison with those in the North Pacific—the LO of these species: Axoprunum

acquilonium (=Stylacontarium acquilonium in the original paper), Schizodiscus

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18

japonicus (=Spongodiscus sp. in the original paper), Amphimelissa setosa and

Lychnocanoma. sakaii (=L. nipponica sakaii in the original paper). These datum levels

are also isochronous between the Japan Sea and the North Pacific, except for the LO of

Ax. acquilonium (Motoyama, 1996; Itaki et al. 2007; Kamikuri and Motoyama, 2007).

We defined four new radiolarian zones for the Japan Sea based on four radiolarian

datum; the LOs of Am. setosa, S. japonicus and Ax. acquilonium, and the ET from

Cycladophora sphaeris to C. davisiana (Figures 2, 3). Of the new zonations for the

Japan Sea, the L. sakaii Zone and A. setosa Zone can be applied to the sediment of the

North Pacific, but the S. japonicus Zone and Hexacontium minerva Zone cannot be

applied to North Pacific sediment because the LO of Ax. acquilonium is diachronous

from the Japan Sea and the North Pacific. The LO of Ax. acquilonium is at 1.7 Ma in the

Japan Sea but is at 0.3 Ma in the North Pacific (Morley and Nigrini, 1995; Kamikuri et

al., 2004, 2007).

Matsuzaki et al. (2014) proposed eight new radiolarian zones based on 17

radiolarian datum levels in the Late Quaternary for the mixed water region of the

Northwest Pacific. Of these, four events (FO of Spongaster tetras irregularis,

Cyrtidosphaera reticulata, Spongoliva ellipsoids and Ceratospyris problematica),

which defined their respective zones, were not observed in the Japan Sea because these

species are basically subtropical or transitional in their geographic distribution.

Conclusions

Core samples were collected in the Japan Sea in IODP Exp. 346 in order to study

the atmosphere-ocean linkage related to the East Asian monsoonal system. More than

6000 m of Quaternary to middle Miocene sediments were recovered from seven sites.

Radiolarians, which are comprised of opal, are well preserved in the sea floor sediments

Accepted manuscript

19

of the Japan Sea and were used to establish biostratigraphy for more precise dating and

correlation of sedimentary sequences drilled at IODP Sites U1422–U1427 and U1430.

The ages of 41 radiolarian datum events recognized in this study were updated based on

the geologic time scale (GTS) of Ogg (2012) by extrapolation of each horizon within

each magnetic chron. In this study, we subdivided and dated the core materials mainly

using the radiolarian zonation of Funayama (1988), Motoyama (1996) and Itaki

(2001b); four newly established Quaternary radiolarian zones can be applied to the

Japan Sea. The sedimentary sequences were divided into six zones from the

Ceratospyris borealis Zone to the Hexacontium parviakitaense Zone at Site U1422,

eight zones from the C. borealis Zone to the Larcopyle pylomaticus Zone at Sites

U1423, U1424 and U1426, fourteen zones from the C. borealis Zone to the Eucyrtidium

inflatum Zone at Sites U1425 and U1430, and four zones from the C. borealis to the

Schizodiscus japonicus Zone at Site U1427. The absence or extremely rare occurrence

Stylatractus universus and E. matuyamai indicate that these species inhabited deeper

waters and have not been able to migrate into the Japan Sea across the Tsugaru Strait

since the Pliocene.

Faunal references

Figure 5

Amphimelissa setosa (Cleve, 1889). Kruglikova, 1989, p. 473, pl. 3, figs. 1–25.

Axoprunum acquilonium (Hays, 1970). Matsuzaki et al., 2015, p. 17, figs. 5.1–5.3.

Calocyclas motoyamai Kamikuri, 2010. Kamikuri, 2010, p. 100, pl. 7, fig. 1a–b.

Cycladophora davisiana Ehrenberg, 1862. Motoyama, 1997, p. 60, pl. 1, figs. 4–10.

Cycladophora nakasekoi Motoyama, 1996. Motoyama, 1996, p. 243, pl. 4, figs. 1a–3b.

Cycladophora sphaeris (Popova, 1989): Spuroclathrocyclas sphaeris Popova, 1989.

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Popova, 1989, p. 73, pl. 11, fig. 17, pl. 12, fig. 3: Cycladophora sakaii Motoyama,

1996. Motoyama, 1996, p. 246, pl. 4, figs. 4a–6b: Cycladophora sphaeris (Popova,

1989). Kamikuri, in press, fig. 8.5.

Cyrtocapsella tetrapera (Haeckel, 1887). Wolfart, 1981, p. 497, pl. 3, fig. 4.

Cyrtocapsella japonica Nakaseko, 1963. Nakaseko, 1963, p. 193, pl. 4, figs. 1–3.

Dendrospyris? sakaii Sugiyama and Furutani, 1992. Sugiyama and Furutani, 1992, p.

204, pl. 13, figs. 3, 6, pl. 20, figs. 3, 4c: Dendrospyris sachalinensis Vituchin, 1993.

Vituchin, 1993, p. 86, pl. 26, figs. 6–8, pl. 29, fig. 13.

Dendrospyris uruyaensis Kamikuri, 2010. Kamikuri, 2010, p. 100, pl. 5, figs. 7–9,

26–28, pl. 7, figs. 9–12.

Dictyophimus bullatus Morley and Nigrini, 1995. Morley and Nigrini, 1995, p. 79, pl. 4,

figs. 5, 9, 10: Dictyophimus robustus Motoyama, 1996. Motoyama, 1996, p. 246, pl.

6, figs. 1a–2c.

Eucyrtidium asanoi Sakai, 1980. Sakai, 1980, p. 709, pl. 7, figs. 12a–14b.

Eucyrtidium inflatum Kling, 1973. Kling, 1973, p. 636, pl. 11, figs. 7, 8, pl. 15, figs.

7–10.

Eucyrtidium matuyamai Hays, 1970. Hays, 1970, p. 213, pl. 1, figs. 7–9.

Hexacontium akitaense (Nakaseko, 1971): Hexacontium akitaensis (Nakaseko, 1971)

[sic]. Kamikuri, 2010, p. 98, pl. 1, figs. 7a–8b, 10a–12, pl. 4, fig. 16.

Hexacontium parviakitaense Kamikuri, 2010: Hexacontium parviakitaensis Kamikuri,

2010 [sic]. Kamikuri, 2010, p. 98, pl. 1, figs. 9a, b, 13a–14b, pl. 4, fig. 15.

Larcopyle pylomaticus (Riedel, 1958). Lazarus et al., 2005, p. 115, pl. 9, figs. 1–3, 6,

10?, 12? (not 4, 5, 7–9, 11): Spongurus? pylomaticus borealis Kruglikova, 1974.

Matsuzaki et al., 2015, p. 25, figs. 6.38, 6.39.

Lipmanella hister (Petrushevskaya, 1975). Sugiyama and Furutani, 1992, p. 209, pl. 13,

figs. 7, 8.

Lipmanella redondoensis (Campbell and Clark, 1944). Funakawa, 2000, p. 108, pl. 4,

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21

figs. 2a–3c, pl. 7, figs. 6a–6c, text-fig. 8.

Lithelius barbatus Motoyama, 1996. Motoyama, 1996, p. 243, pl. 3, figs. 11–14.

Lithopera renzae Sanfilippo and Riedel, 1970. Sanfilippo and Riedel, 1970, p. 454, pl. 1,

figs. 21–23, 27.

Lychnocanoma magnacornuta Sakai, 1980. Motoyama, 1996, p. 248, pl. 5, figs. 10a–11.

Lychnocanoma parallelipes Motoyama, 1996. Motoyama, 1996, p. 248, pl. 5, figs.

12a–14.

Lychnocanoma sakaii Morley and Nigrini, 1995. Kamikuri, 2010, p. 101, pl. 6, fig. 1a,

b.

Schizodiscus japonicus Matsuzaki and Suzuki, 2014. Matsuzaki et al., 2014, p. 209, pl.

2, figs. 27–30: Spongodiscus sp. Ling, 1973. Ling, 1973, p. 778, pl. 1, figs. 9, 10.

Matul et al., 2002, p. 30, figs. 4.3, 4.4. Ikenoue et al., 2016, p. 40, pl. 2, figs. 1–20.

Siphocampe arachnea (Ehrenberg, 1862) group. Nigrini, 1977, p. 255, pl. 3, figs. 7, 8.

Stylosphaera magnaporulosa (Clark and Campbell, 1942). Sugiyama and Furutani,

1992, p. 202, pl. 12, figs. 5–7, 10, pl. 15, figs. 3, 4, 6, 7.

Acknowledgments

The authors are grateful to John Rogers and Noritoshi Suzuki for reviewing the

manuscript. We are grateful to Ryuji Tada, Rick Murray, and the other scientists and

crew members of Exp. 346 of JOIDES Resolution for their support and prompt attention

to our requests. Samples were provided by the Integrated Ocean Drilling Program

(IODP). This work was also partly supported by Japan Society for the Promotion of

Science (JSPS) KAKENHI Grant Numbers 15K17780 (S. Kamikuri), 25400504 and

23221022 (T. Itaki); and JSPS Research Fellowship for Young Scientists (K.M.

Matsuzaki).

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22

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Accepted manuscript

30

radiolarian biostratigraphic zones and GPTS conversion tables. Marine


Sanfilippo, A. and Riedel, W. R., 1970: Post-Eocene “closed” theoperid radiolarians.


Shilov, V. V., 1995: Miocene - Pleistocene radiolarians from Leg 145, North Pacific. In,

Rea, D. K. Basov, I. A., Scholl, D. W. and Allan, J. F. eds., Proceedings of the

Ocean Drilling Program, Scientific Results, vol. 145, p. 93–116. Ocean Drilling

Program, College Station, TX.

Spencer-Cervato, C., Lazarus, D. B., Beckmann, J. -P., von Salis Perch-Nielsen, K. and

Biolzi, M., 1993: New calibration of Neogene radiolarian events in the North Pacific.

Marine Micropaleontology, vol. 21, p. 261–293.

Sugano, K. and Nakaseko, K., 1968: On the assemblage of fossil radiolarians in the

neighbourhood of the Nishiyama Oil Field, Niigata Prefecture, Japan–Studies of

fossil radiolarian stratigraphy of the Niigata Prefecture, Japan (Part 1). Memoirs of

Osaka Kyouiku University, vol. 17, p. 1–14. (in Japanese with English abstract)

Sugano, K. and Nakaseko, K., 1971: On the assemblage of fossil Radiolaria in the

neighbord of Kitakanbara Plain, Niigata Prefecture, Japan–Studies of fossil

radiolarian stratigraphy of the Niigata Prefecture, Japan (Part 3). Memoirs of Osaka

Kyouiku University, vol. 20, 63–79. (in Japanese with English abstract)

Sugiyama, K. and Furutani, H., 1992: Middle Miocene radiolarians from the Oidawara

Formation, Mizunami Group, Gifu Prefecture, central Japan. Bulletin of the

Mizunami Fossil Museum, vol. 19, p. 199–213.

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Palaeoclimatology, Palaeoecology, vol. 108, p. 487–508.

Tada, R., Murray, R. W., Alvarez Zarikian, C. A., Anderson, W. T. Jr., Bassetti, M. -A.,

Brace, B. J., Clemens, S. C., da Costa Gurgel, M. H., Dickens, G. R., Dunlea, A. G.,

Gallagher, S. J., Giosan, L., Henderson, A. C. G., Holbourn, A. E., Ikehara, K.,

Accepted manuscript

31

Irino, T., Itaki, T., Karasuda, A., Kinsley, C. W., Kubota, Y., Lee, G. S., Lee, K. E.,

Lofi, J., Lopes, C. I. C. D., Peterson, L. C., Saavedra-Pellitero, M., Sagawa, T.,

Singh, R. K., Sugisaki, S., Toucanne, S., Wan, S., Xuan, C., Zheng, H. and Ziegler,

M., 2015: Expedition 346 summary. In, Tada, R., Murray, R.W., Alvarez Zarikian,

C.A., the Expedition 346 Scientists eds., Proceedings of Integrated Ocean Drilling

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10.2204/iodp.proc.346.101.2015

Tochilina, S. V., 1985: Biostratigraphy of the Cenozoic North-western Pacific Ocean.

Akademiya Nauk SSSR, Tikhookeanskiy Institut Okeanologii DVNTs, no. 114, p.

1–133. (in Russian with English abstract)

Vasilenko, L. N., 2015: Upper Cenozoic radiolarians from the sedimentary cover of

Peter the Great Seamount (Sea of Japan). Bulletin of Kamchatka Regional

Association “Educational-Scientific Center” Earth Sciences, vol. 4, p. 80–93. (in

Russian with English abstract)

Vitukhin, D. I., 1993: Subdivision of the Russian Far East Cenozoic sediments based on

radiolarians. Geologicheskii Institut, Rossiskaya Akademiya Nauk, Trudi, vol. 485, p.

1–104. (in Russian with English abstract)

Weaver, F. M., Casey, R. E. and Perez, A. M., 1981: Stratigraphic and

paleoceanographic significance of early Pliocene to middle Miocene radiolarian

assemblages from Northern to Baja California. In, Garrison, G. and Douglas, R. E.

eds., The Monterey Formation and Related Siliceous Rocks of California, p. 71–86.

Society of Economic Paleontologists and Mineralogists, Los Angels, California.

Wolfart, R., 1981: Neogene radiolarians from the eastern North Pacific (off Alta and

Baja California), Deep Sea Drilling Project Leg 63. In, Yeats, R. S., Haq, B. U. et al.

eds., Initial Reports of the Deep Sea Drilling Project, vol. 63, p. 473–506. U. S.

Government Printing Office, Washington, DC.

Accepted manuscript

32

Captions.

Figure 1. Map showing locations of Deep Sea Drilling Project (DSDP), Ocean Drilling

Program (ODP), and Integrated Ocean Drilling Program (IODP) sites and oceanic

currents. (From Tada et al., 2015)

Figure 2. Correlation of radiolarian zones for the middle to high latitude of North

Pacific and the Japan Sea. Geomagnetic polarity time scale is after Ogg (2012).

Figure 3. Intercorrelation of IODP Sites U1422–1427, and U1430 based on radiolarian

zones.

Figure 4. Age-depth plot of IODP Sites U1422–1427 and U1430. Age is adopted from

GTS2012 (Ogg, 2012).

Figure 5. Photographs of selected radiolarian species identified in this study. 1,

Cycladophora nakasekoi Motoyama, Sample 346-1430A-17H-CC, sl. 1, L44/1; 2,

Cycladophora sphaeris (Popova), Sample 346-1430A-9H-4, 8-10 cm, sl. 1, R42/2; 3,

Dendrospyris uruyaensis Kamikuri, Sample 346-1430A-25H-CC, sl. 1, N56/0; 4,

Hexacontium parviakitaense Kamikuri, Sample 346-1430A-8H-CC, sl. 1, R42/3; 5,

Hexacontium akitaense (Nakaseko), Sample 346-1430A-8H-CC, sl. 1, R42/3; 6,

Eucyrtidium inflatum Kling, Sample 346-1430A-29H-CC, sl. 1, S46/3; 7, Lithopera

renzae Sanfilippo and Riedel, Sample 346-1430A-28H-CC, sl. 1, Z53/3; 8,

Lipmanella redondoensis (Campbell and Clark), Sample 346-1430A-27H-CC, sl. 1,

U37/2; 9, Larcopyle pylomaticus (Riedel), Sample 346-1430A-9H-4, 8-10 cm, sl. 1,

G35/4; 10, Cyrtocapsella japonica Nakaseko, Sample 346-1430A-20H-CC, sl. 1,

X58/0; 11, Siphocampe arachnea (Ehrenberg) group, Sample 346-1430A-8H-CC, sl.

Accepted manuscript

33

1, S30/1; 12, Amphimelissa setosa (Cleve), Sample 346-1430A-3H-CC, sl. 1, M57/0;

13, Schizodiscus japonicus Matsuzaki and Suzuki, Sample 346-1425B-3H-4, 51-53

cm, sl. 1; 14, Axoprunum acquilonium (Hays), Sample 346-1430A-6H-CC, sl. 1,

U37/3; 15, Lychnocanoma magnacornuta Sakai, Sample 346-1430A-21H-CC, sl. 1,

N33/4; 16, Lychnocanoma sakaii Morley and Nigrini, Sample 346-1425B-1H-5,

98-100 cm, sl. 1.

Table 1. Summary of radiolarian datum events at IODP Sites U1422–1427, and U1430.

The following abbreviations are used in this study to express events; FO, first

occurrence; LO, last occurrence; RI, rapid increase; RD, rapid decrease. The

concept of evolutionary transition (ET) follows that of Sanfilippo and Nigrini

(1998). The definition of radiolarian zonations was indicated by the use of bold font.

Data source: a, Itaki et al., 2007; b, Matul et al., 2002; c, Motoyama, 1996; d,

Matsuzaki and Suzuki, in press; e, Itaki per. com.; f, Ikenoue et al., 2016; g,

Kamikuri et al., 2004; h, Kamikuri et al., 2007; i, Kamikuri, 2010; j, Funayama,

1988.

Appendix. Stratigraphic distribution of selected radiolarian taxa.

Figure 1

C5

C3A

C3B

C4A

C4

M i

o c

e n

eLa

teP

l i o

c e

n e La

teLa

teEa

rlyPl

eist

ocen

e

1

2

3

4

5

6

7

8

9

0

10

11

12

Early

C3

C2

C2A

C1

n

r

n

r

n

r

n

r

n

rnr

n

r

n

r

n

r

Mid

dle

13

14

15

n

n

n

n

n

n

r

r

r

r

r

rC5B

C5AD

C5ACC5ABC5AA

C5A

Schizodiscus japonicus

Amphimelissa setosa

LO L. sakaiiLO A. setosaLO S. japonicus

LO A. acquilonium

LO H. parviakitaense

LO D. bullatus

L. hannaiL. klingi

LO D. bullatus

FO L. pylomaticus

LO L. redondoensis

LO L. parallelips

LO L. magnacornuta

FO L. magnacornuta

LO Cyrtocapsella japonica

RD Cyrtocapsella tetrapera

RI L. barbatus

FO L. parallelips

Lychnocanoma sakaiiCeratospyris borealis

E. asanoi

Botryostrobus aquilonaris

Stylatractus universus

Eucyrtidium matuyamai

Dictyophimus bullatus

Litheliusbarbatus

Lychnocanoma parallelips

Cycladophora funakawai


Lychnocanoma magnacornuta

Lychnocanoma nipponica magnacornuta

Eucyrtidium inflatum

Melittosphaeramagnaporulosa

Cyrtocapsella tetrapera

Lychnocanium nipponicum

Thecosphaera japonicaCycladophora

sphaeris

Cycladophora davisiana

Clathrocyclas bicornis - Spurioclath. sphaeris

Hexacontiumparviakitaense

Hexacontoium minerva


Larcopylepylomaticus




Axoprunumacquilonium

Litheliusbarbatus



Chr

on

Epoc

h

Tim

e (M

a)

Pola

rity

GTS2012 Radiolarian zonation

Funayama (1988)

Vasilenko (2015) Kamikuri et al. (2004)

Motoyama (1996) Nakaseko &Sugano (1973)

Kamikuri (in press)

North Pacific Japan Sea

This study

Mid

dle

C. reynoldsi

C. japonica

b

a

Spurioclath. urymensis

Figure 2

Dep

th (m

ccs

f-a)

0

100

50

150

250

350

200

300

400

450

500

1422Site

1, 23

4

5

142312

3

4

5

6

6

6

7

78

9

101112

13,15

78-11

1427

1

1

2

2

312

13

14

1516

1425 1426

1, 21, 2

33 3

4

5

142413

4

4

4

5 5

5

1430

1 LO L. sakaii2 LO A. setosa3 LO S. japonincus4 LO A. acquilonium

6 LO D. bullatus13 LO L. magnacornuta

15 FO L. magnacornuta14 LO C. japonica

16 RD C. tetrapera7 FO D. bullatus

9 FO L. pylomaticus

8 LO L. redondoensis

12 FO L. parallelipes

10 LO L. parallelipes11 RI L. barbatus

5 ET C. davisiana

0.054

0.085

0.29

1.7

2.57

3.8/4.3

4.3/4.5

5.2/5.6

5.9/6.4

6.8/7.0

7.2/7.4

9.1

9.9/10.1

11.7/11.9

12.8

Schizodiscus japonicus

Amphimelissa setosa

Lychnocanoma sakaii

Ceratospyris borealis


Hexacontiumparviakitaense

Hexacontium minerva





Litheliusbarbatus



Radiolarian zonation

Time (Ma)

5.0/5.1

Figure 3

Epoch

Time (Ma)

Pleistocene Pliocene

Site U1427

MioceneLate Late MiddleEarlyEarlyMiddleLate

1 2 3 4 5 60 7 8 9 10 11 12 13 14 15 16

Dep

th (m

ccs

f-a)

0

100

50

150

250

350

200

300

400

450

500

Site U1430

Site U1425

Site U1426

Site U1424

Site U1423

Site U1422

Figure 4

100 µm1

3

87

6

15

5

10

9

2

4

11

14

12

16

13

Figure 5

Table 1a

U1422C U1423A U1423B U1424A

Datum Age (Ma) Source Sample CCSF-A (m) Sample CCSF-A (m) Sample CCSF-A (m) Sample CCSF-A (m) 1 LO Lychnocanoma sakaii 0.054 a 1H-CC/2H-CC 4.16/14.50 1H-3, 70-72cm/1H-4, 70-72cm 3.70/5.20 top/1H-CC 0.00/6.652 LO Amphimelissa setosa 0.085 a 1H-CC/2H-CC 4.16/14.50 1H-5, 72-74cm/1H-CC 6.72/7.103 LO Schizodiscus japonicus 0.29 b 2H-CC/3H-CC 14.50/24.81 3H-5, 70-72cm/3H-6, 70-72cm 24.36/25.86 1H-CC/2H-CC 6.65/16.234 Eucyrtidium matuyamai occurrence 1.1 c 7H5, 40-42 62.89 no data no data 5H-CC 44.6305 FO Amphimelissa setosa 1.48 d 8H-CC/9H-4, 70-72cm 77.47/82.846 LO Axoprunum acquilonium 1.7 e 10H-7, 40-42cm/10H-CC 95.31/95.49 9H-CC/10H-4, 70-72cm 87.20/92.69 4H-CC/5H-CC 35.23/44.637 LO Cycladophora sphaeris 2.18-2.21 f 13H-CC/14H-CC 124.94/135.58 12H-CC/13H-CC 117.24/127.68 8H-CC/9H-CC 73.00/82.758 ET C. sphaeris to C. davisiana 2.56-2.57 f 16H-CC/17H-3, 10-12cm 145.54/149.06 12H-CC/13H-CC 117.24/127.24 8H-CC/9H-CC 73.00/82.759 FO Cycladophora davisiana 2.62-2.66 f 18H-CC/19H-CC 155.69/160.51 12H-CC/13H-CC 115.87/126.31 8H-CC/9H-CC 73.00/82.75

10 LO Hexacontium parviakitaense 2.87-2.90 f 19H-CC/20H-3, 83-85cm 160.51/164.14 13H-CC/14H-CC 126.31/136.01 8H-CC/9H-CC 73.00/82.7511 FO Hexacontium parviakitaense 3.8-4.3 g 18H-CC/19H-CC 175.52/185.58 12H-CC/13H-CC 111.29/120.9412 LO Dictyophimus bullatus 3.8-4.3 g, h 19H-CC/20H-CC 185.58/195.16 no data no data13 RD Siphocampe arachnea group 4.4-4.5 g 19H-CC/20H-CC 185.58/195.16 13H-CC/14H-CC 120.94/130.3014 FO Dictyophimus bullatus 4.3-4.5 g, h 21H-CC/22H-CC 205.01/214.85 22H-CC/23H-CC 199.34/209.20 no data no data15 RI Siphocampe arachnea group 4.6-4.7 g 25H-CC/26H-CC 228.17/237.72 15H-CC/16H-CC 139.91/149.3916 LO Lipmanella redondoensis 5.0-5.1 g17 FO Larcopyle pylomaticus 5.2-5.6 g18 RD Lithelius barbatus 5.2-5.6 g19 LO Lychnocanoma parallelipes 5.9-6.4 g20 FO Axoprunum acquilonium 6.8-7.0 h21 RI Lithelius barbatus 6.8-7.0 h22 LO Cycladophora nakasekoi 6.7-7.7 g23 FO Lychnocanoma parallelipes 7.2-7.4 h24 FO Cycladophora sphaeris 8.5 g25 LO Lychnocanoma magnacornuta 9.1 h26 FO Cycladophora nakasekoi 9.7-10.2 g27 LO Cyrtocapsella japonica 9.9-10.1 h28 LO Dendrospyris uruyaensis 10.8-12.0 i29 LO Hexacontium akitaense 10.8-12.0 i30 FO Hexacontium akitaense 11.3-11.5 i31 FO Lychnocanoma magnacornuta 11.7-11.9 h32 FO Dendrospyris uruyaensis 11.7-11.9 i33 LO Eucyrtidium inflatum 11.7-11.9 h34 LO Calocyclas motoyamai 11.7-11.9 i35 LO Lithopera renzae 12.1-12.3 h36 RD Cyrticapsella tetrapera 12.8 j37 FO Calocyclas motoyamai 12.9-13.1 i38 LO Stylosphaera magnaporulosa 13.0-13.3 h39 LO Eucyrtidium asanoi 13.8-14.1 h40 LO Dendrospyris sakaii 14.6-14.8 h41 LO Lipmanella hister 14.8-15.0 h

Table 1b

U1425B U1425D U1426A U1427A

Datum Age (Ma) Source Sample CCSF-A (m) Sample CCSF-A (m) Sample CCSF-A (m) Sample CCSF-A (m) 1 LO Lychnocanoma sakaii 0.054 a 1H-4, 68-70cm/1H-5, 98-100cm 5.18/6.98 1H-CC/2H-CC 2.51/12.71 2H-CC/3H-CC 10.92/21.642 LO Amphimelissa setosa 0.085 a 1H-4, 68-70cm/1H-5, 98-100cm 5.18/6.98 1H-CC/2H-CC 2.51/12.71 5H-CC/6H-CC 39.32/49.943 LO Schizodiscus japonicus 0.29 b 2H-5, 70-72cm/2H-CC 16.06/19.10 3H-CC/4H-CC 22.94/33.37 10H-CC/11H-CC 89.56/100.184 Eucyrtidium matuyamai occurrence 1.1 c no data no data 13H-CC 127.1605 FO Amphimelissa setosa 1.48 d 6H-5, 11-13cm/6H-CC 57.01/60.54 81X-CC/82X-1, 50-52cm 512.72/513.356 LO Axoprunum acquilonium 1.7 e 6H-CC/7H-5, 71-73cm 60.54/67.69 19H-CC/20H-CC 193.82/204.777 LO Cycladophora sphaeris 2.18-2.21 f 9H-3, 4-6cm/9H-3, 71-73cm 84.99/85.66 24H-CC/25H-CC 244.01/252.998 ET C. sphaeris to C. davisiana 2.56-2.57 f 8H-CC/9H-3, 4-6cm 81.24/84.99 25H-CC/26H-CC 252.99/262.919 FO Cycladophora davisiana 2.62-2.66 f 10H-CC/11H-4, 70-72cm 98.72/104.59 28H-CC/29H-CC 282.61/286.744

10 LO Hexacontium parviakitaense 2.87-2.90 f 8H-5, 137-139cm/8H-7, 38-40cm 79.00/81.01 30H-CC/31H-CC 291.50/296.1711 FO Hexacontium parviakitaense 3.8-4.3 g 17H-CC/18H-CC 126.81/131.96 55H-CC/56H-CC 403.72/408.3012 LO Dictyophimus bullatus 3.8-4.3 g, h 18H-CC/19H-CC 131.96/136.9013 RD Siphocampe arachnea group 4.4-4.5 g 17H-CC/18H-CC 126.81/131.96 55H-CC/56H-CC 403.72/408.3014 FO Dictyophimus bullatus 4.3-4.5 g, h 21H-4, 19-21cm/21H-6, 19-21cm 147.01/150.0115 RI Siphocampe arachnea group 4.6-4.7 g 23H-3, 129-131cm/23H-5, 129-131cm 167.01/170.01 57H-CC/58H-CC 412.87/417.1916 LO Lipmanella redondoensis 5.0-5.1 g 22H-5, 10-12cm/22H-CC 158.98/162.6517 FO Larcopyle pylomaticus 5.2-5.6 g 25H-6, 91-93cm/25H-CC 191.00/203.4118 RD Lithelius barbatus 5.2-5.6 g 25H-2, 90-92cm/25H-4, 91-93cm 184.99/188.0019 LO Lychnocanoma parallelipes 5.9-6.4 g 28H-3, 147-149cm/28H-CC 217.00/221.0020 FO Axoprunum acquilonium 6.8-7.0 h 30H-CC/32X-CC 239.32/244.2921 RI Lithelius barbatus 6.8-7.0 h 30H-5, 31-33cm/30H-CC 236.00/239.3222 LO Cycladophora nakasekoi 6.7-7.7 g 34H-4, 46-48cm/34H-CC 258.00/262.6423 FO Lychnocanoma parallelipes 7.2-7.4 h 33H-CC/34H-4, 46-48cm 253.16/258.0024 FO Cycladophora sphaeris 8.5 g 38H-1, 101-103cm/38H-CC 283.00/286.7125 LO Lychnocanoma magnacornuta 9.1 h 47H-CC/48H-CC 329.81/335.5526 FO Cycladophora nakasekoi 9.7-10.2 g 56X-CC/57H-CC 381.25/384.6027 LO Cyrtocapsella japonica 9.9-10.1 h no data no data28 LO Dendrospyris uruyaensis 10.8-12.0 i no data no data29 LO Hexacontium akitaense 10.8-12.0 i30 FO Hexacontium akitaense 11.3-11.5 i31 FO Lychnocanoma magnacornuta 11.7-11.9 h 56X-CC/57X-CC 381.25/384.60 57H-CC/58H-CC 390.86/394.9332 FO Dendrospyris uruyaensis 11.7-11.9 i no data no data no data no data33 LO Eucyrtidium inflatum 11.7-11.9 h 59X-CC/60H-CC 409.94/417.66 58H-CC/59H-CC 394.93/399.7734 LO Calocyclas motoyamai 11.7-11.9 i35 LO Lithopera renzae 12.1-12.3 h36 RD Cyrticapsella tetrapera 12.8 j 60H-CC/61H-CC 404.41/405.8237 FO Calocyclas motoyamai 12.9-13.1 i38 LO Stylosphaera magnaporulosa 13.0-13.3 h39 LO Eucyrtidium asanoi 13.8-14.1 h40 LO Dendrospyris sakaii 14.6-14.8 h41 LO Lipmanella hister 14.8-15.0 h

Table 1c

U1427B U1427C U1430A

Datum Age (Ma) Source Sample CCSF-A (m) Sample CCSF-A (m) Sample CCSF-A (m)1 LO Lychnocanoma sakaii 0.054 a 3H-4, 45-47cm/3H-5, 32-34cm 20.06/21.43 2H-6, 15-17cm/3H-4, 45-47cm 16.30/23.06 top/1H-CC 0.00/3.682 LO Amphimelissa setosa 0.085 a 4H-5, 48-50cm/5H-3, 48-50cm 30.63/37.16 4H-5, 45-47cm/5H-4, 45-47cm 33.79/42.90 2H-4, 68-70cm/2H-CC 9.14/13.523 LO Schizodiscus japonicus 0.29 b 12H-7, 46-48cm/14H-3, 50-52cm 102.72/109.75 12H-5, 45-47cm/14H-3, 45-47cm 109.02/124.54 2H-CC/3H-4, 68-70cm 13.52/19.284 Eucyrtidium matuyamai occurrence 1.1 c no data no data5 FO Amphimelissa setosa 1.48 d 5H-CC/6H-4, 68-70cm 43.69/49.156 LO Axoprunum acquilonium 1.7 e 6H-4, 68-70cm/6H-CC 49.15/53.567 LO Cycladophora sphaeris 2.18-2.21 f 6H-CC/7H-4, 68-70cm 53.56/59.208 ET C. sphaeris to C. davisiana 2.56-2.57 f 6H-CC/7H-4, 68-70cm 53.56/59.209 FO Cycladophora davisiana 2.62-2.66 f 7H-4, 68-70cm/7H-CC 59.20/63.61

10 LO Hexacontium parviakitaense 2.87-2.90 f 7H-4, 68-70cm/7H-CC 59.20/63.6111 FO Hexacontium parviakitaense 3.8-4.3 g 8H-CC/9H-1, 68-70cm 73.67/74.3312 LO Dictyophimus bullatus 3.8-4.3 g, h 9H-1, 68-70cm/9H-2, 68-70cm 74.33/75.8313 RD Siphocampe arachnea group 4.4-4.5 g 8H-4, 68-70cm/8H-CC 69.22/73.6714 FO Dictyophimus bullatus 4.3-4.5 g, h 9H-2, 68-70cm/9H-3, 68-70cm 75.83/77.3315 RI Siphocampe arachnea group 4.6-4.7 g 9H-2, 68-70cm/9H-3, 68-70cm 75.83/77.3316 LO Lipmanella redondoensis 5.0-5.1 g 9H-4, 68-70cm/9H-4, 120-122cm 78.83/79.3517 FO Larcopyle pylomaticus 5.2-5.6 g 9H-4, 68-70cm/9H-4, 120-122cm 78.83/79.3518 RD Lithelius barbatus 5.2-5.6 g no data no data19 LO Lychnocanoma parallelipes 5.9-6.4 g 9H-4, 68-70cm/9H-4, 120-122cm 78.83/79.3520 FO Axoprunum acquilonium 6.8-7.0 h 9H-4, 120-122cm/9H-5, 11-13cm 79.35/79.7621 RI Lithelius barbatus 6.8-7.0 h no data no data22 LO Cycladophora nakasekoi 6.7-7.7 g 9H-4, 120-122cm/9H-5, 11-13cm 79.35/79.7623 FO Lychnocanoma parallelipes 7.2-7.4 h 9H-5, 11-13cm/9H-5, 70-72cm 79.76/80.3524 FO Cycladophora sphaeris 8.5 g 10H-4, 68-70cm/10H-5, 70-72cm 89.23/90.7525 LO Lychnocanoma magnacornuta 9.1 h 16H-4, 70-72cm/16H-5, 68-70cm 149.94/151.4226 FO Cycladophora nakasekoi 9.7-10.2 g 19H-CC/20H-4, 68-70cm 185.41/191.0627 LO Cyrtocapsella japonica 9.9-10.1 h 20H-4, 68-70cm/20H-CC 191.06/194.5528 LO Dendrospyris uruyaensis 10.8-12.0 i 22H-4, 68-70cm/22H-CC 211.39/215.2629 LO Hexacontium akitaense 10.8-12.0 i 22H-4, 68-70cm/22H-CC 211.39/215.2630 FO Hexacontium akitaense 11.3-11.5 i 23H-4, 68-70cm/23H-CC 220.91/225.3431 FO Lychnocanoma magnacornuta 11.7-11.9 h 28H-1, 70-72cm/28H-3, 25-27cm 255.99/258.5632 FO Dendrospyris uruyaensis 11.7-11.9 i 28H-1, 70-72cm/28H-3, 25-27cm 255.99/258.5633 LO Eucyrtidium inflatum 11.7-11.9 h 28H-1, 70-72cm/28H-3, 25-27cm 255.99/258.5634 LO Calocyclas motoyamai 11.7-11.9 i 28H-1, 70-72cm/28H-3, 25-27cm 255.99/258.5635 LO Lithopera renzae 12.1-12.3 h 28H-3, 25-27cm/28H-CC 258.56/260.0036 RD Cyrticapsella tetrapera 12.8 j 29H-CC/30X-CC 264.43/264.6337 FO Calocyclas motoyamai 12.9-13.1 i 29H-CC/30H-CC 264.43/264.6338 LO Stylosphaera magnaporulosa 13.0-13.3 h 29X-CC/30X-CC 264.43/264.6339 LO Eucyrtidium asanoi 13.8-14.1 h 30X-CC/31X-CC 264.63/270.1340 LO Dendrospyris sakaii 14.6-14.8 h 30H-CC/31X-CC 264.63/270.1341 LO Lipmanella hister 14.8-15.0 h 30H-CC/31X-CC 264.63/270.13

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U1422C 1 H CC 0 5 4.15 M F AU1422C 2 H CC 0 3 14.49 G A P PU1422C 3 H CC 0 5 24.80 G A R P AU1422C 4 H CC 0 5 35.09 M R RU1422C 5 H CC 0 4 45.06 G A A CU1422C 6 H CC 0 4 54.94 BU1422C 7 H 5 40 42 62.89 G R PU1422C 7 H CC 0 7 66.21 BU1422C 8 H 7 41 43 76.05 P R P AU1422C 8 H CC 0 5 76.23 P RU1422C 9 H 3 111 113 81.57 P R CU1422C 9 H CC 0 5 83.94 BU1422C 10 H 2 20 22 87.52 P R PU1422C 10 H 4 70 72 91.06 M R RU1422C 10 H 7 40 42 95.31 P R CU1422C 10 H CC 0 6 95.49 M F FU1422C 11 H CC 0 5 105.32 G C C C RU1422C 12 H CC 0 5 115.62 G A F A R RU1422C 13 H CC 0 5 124.94 G F R R RU1422C 14 H CC 0 5 135.58 G C F R R FU1422C 15 H 3 71 73 139.23 G R P CU1422C 15 H CC 0 5 140.59 G C R C CU1422C 16 H 2 50 52 142.68 G C P R C CU1422C 16 H CC 0 5 145.54 G A R F R FU1422C 17 H 3 10 12 149.06 G C RU1422C 17 H CC 0 5 150.82 M R C P RU1422C 18 H 3 73 75 154.65 G R R RU1422C 18 H CC 0 5 155.69 G C P R CU1422C 19 H 3 65 67 159.25 M C RU1422C 19 H CC 0 5 160.51 G A R R F RU1422C 20 H 3 83 85 164.14 G C P C P R AU1422C 20 H CC 0 5 165.12 G C F R FU1422C 21 H CC 0 5 169.85 G A A F R RU1422C 22 H CC 0 5 174.41 G A R A R FU1422C 23 H CC 0 5 179.15 G A C A CU1422C 24 H CC 0 5 183.82 G A C F CU1422C 25 H CC 0 6 188.65 G A A R F FU1422C 26 H CC 0 6 193.23 G C R C R R FU1422C 27 H CC 0 6 197.93 G C R C F R R PU1422C 28 H CC 0 6 202.75 G C R F F RU1422C 29 H CC 0 6 207.31 G C R F F C FU1422C 30 H CC 0 5 212.17 G C F F FU1422C 31 H CC 0 5 216.75 G C R C C C F

No. 1 2 3 4 5 6 7 8 9 10 11 12H

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U1423A 1 H 1 70 72 0.70 G A A

U1423A 1 H 2 70 72 2.20 G C F

U1423A 1 H 3 70 72 3.70 P R F

U1423A 1 H 4 70 72 5.20 G F C

U1423A 1 H 5 72 74 6.72 G F A R

U1423A 1 H CC 0 4 7.10 G F A F

U1423A 2 H 4 130 132 13.57 G C A C P

U1423A 2 H 5 70 72 14.07 G F A C

U1423A 2 H 6 70 72 15.97 G C A F

U1423A 2 H CC 0 5 17.33 M A C F A

U1423A 3 H 5 70 72 24.36 G A A

U1423A 3 H 6 70 72 25.86 G A F A R

U1423A 3 H CC 0 5 27.31 M R R F R F

U1423A 4 H 5 70 72 34.49 G C C P A

U1423A 4 H 6 70 72 35.99 G A A F

U1423A 4 H CC 0 5 37.32 M A F P A

U1423A 5 H 4 70 72 42.92 G A A

U1423A 5 H 5 70 72 44.64 P R F

U1423A 5 H 6 70 72 46.14 G A A F

U1423A 5 H 7 10 12 46.85 M F C C F F

U1423A 5 H CC 0 5 47.32 G C R P P F F

U1423A 6 H 4 70 72 52.84 G A A P

U1423A 6 H 5 70 72 54.34 G C A R

U1423A 6 H 6 70 72 55.84 G C F C

U1423A 6 H CC 0 5 57.13 G A A F R

U1423A 7 H 4 70 72 63.00 G C C A R F

U1423A 7 H 5 70 72 64.50 G A C F C

U1423A 7 H 6 70 72 66.00 G C C F

U1423A 7 H CC 0 5 67.40 G A C F P A

U1423A 8 H 4 70 72 73.10 G C A

U1423A 8 H 5 70 72 74.60 G A F F R

U1423A 8 H 6 70 72 76.10 G C F F

U1423A 8 H CC 0 5 77.47 G A C

U1423A 9 H 4 70 72 82.84 M F C

U1423A 9 H 5 70 72 84.34 G C A

U1423A 9 H 6 70 72 85.84 G C C P

U1423A 9 H CC 0 4 87.20 P R P P

U1423A 10 H 4 70 72 92.68 G A P C P P

U1423A 10 H 5 70 72 94.18 G C R A F R

U1423A 10 H 6 70 72 95.68 G C A F

U1423A 10 H 7 58 60 97.06 G C C R

U1423A 10 H CC 0 4 97.09 G A C A F F

U1423A 11 H 1 70 72 97.99 P R C P P

U1423A 11 H 3 70 72 100.99 G C A F

U1423A 11 H 5 70 72 103.99 M C A R

No. 1 2 3 4 5 6 7 8 9 10 11 12U1423A 11 H CC 0 5 106.84 G A F C RU1423A 12 H 1 70 72 107.01 M A CU1423A 12 H 3 70 72 110.01 M A C RU1423A 12 H 5 70 72 113.01 P R RU1423A 12 H CC 0 5 115.87 G A F F C RU1423A 13 H 1 70 72 117.40 G C C F PU1423A 13 H 3 70 72 120.40 P C F PU1423A 13 H 5 70 72 123.40 G C F CU1423A 13 H CC 0 4 126.31 G A C F FU1423A 14 H 1 70 72 126.98 G C A CU1423A 14 H 3 70 72 129.98 G C AU1423A 14 H 5 70 72 132.98 G C FU1423A 14 H CC 0 5 136.01 G A C R F FU1423A 15 H 1 70 72 136.94 G C C RU1423A 15 H 3 70 72 139.94 G C C RU1423A 15 H 5 70 72 142.94 G C C RU1423A 15 H CC 0 5 145.86 G C P F F P FU1423A 16 H 1 70 72 147.32 G R CU1423A 16 H 3 70 72 150.32 G C C RU1423A 16 H 5 70 72 153.32 G C C FU1423A 16 H CC 0 4 156.38 G C R F CU1423A 17 H 1 70 72 156.84 G C A P FU1423A 17 H 3 70 72 159.84 M R C FU1423A 17 H 5 70 72 162.84 M C C R CU1423A 17 H CC 0 5 165.29 G C R F C F FU1423A 18 H 1 70 72 166.63 M C C CU1423A 18 H 3 70 72 169.63 M C C CU1423A 18 H 5 70 72 172.63 P F CU1423A 18 H CC 0 5 175.52 G A F C F FU1423A 19 H 1 70 72 176.78 P R C P P RU1423A 19 H 3 70 72 179.78 P R P P PU1423A 19 H 5 70 72 182.78 M F AU1423A 19 H CC 0 5 185.58 G C P C CU1423A 20 H 2 70 72 187.91 M F F FU1423A 20 H 4 70 72 190.91 M C C AU1423A 20 H 6 70 72 193.91 M C C AU1423A 20 H CC 0 4 195.15 G A P A P C AU1423A 21 H 2 70 72 197.71 M R F P AU1423A 21 H 4 70 72 200.71 M F AU1423A 21 H 6 70 72 203.71 P F R AU1423A 21 H CC 0 5 205.01 G A P C R AU1423A 22 H 2 70 72 207.39 M C C AU1423A 22 H 4 70 72 210.39 M C CU1423A 22 H 6 100 102 213.69 M A P C AU1423A 22 H CC 0 5 214.85 G A P A AU1423B 2 H 3 70 72 8.23 G C A AU1423B 2 H 4 70 72 9.73 G A AU1423B 2 H 5 70 72 11.23 G A F R CU1423B 2 H 6 70 72 12.73 M F F C CU1423B 3 H 2 70 72 16.60 G C A FU1423B 3 H 3 70 72 18.10 G C A F CU1423B 3 H 4 70 72 19.60 G C A AU1423B 3 H 5 70 72 21.10 G C A CU1423B 3 H 6 70 72 22.60 M F A FU1423B 3 H 7 20 22 23.60 G C A

No. 1 2 3 4 5 6 7 8 9 10 11 12

U1423B 4 H 2 100 102 26.76 G A A P

U1423B 4 H 3 70 72 27.93 P VR P

U1423B 4 H 4 70 72 29.43 G C A R C

U1423B 4 H 5 70 72 30.93 G A R C

U1423B 4 H 6 68 70 32.41 G C A A R

U1423B 4 H 7 40 42 33.63 M F A F R R

U1423B 5 H 2 120 122 36.73 G C A F

U1423B 5 H 3 70 72 37.73 G C A

U1423B 5 H 4 70 72 39.23 G A A R C

U1423B 5 H 5 69 71 40.72 G C P A

U1423B 5 H 6 70 72 42.23 P R

U1423B 6 H 3 70 72 47.94 M F A F

U1423B 6 H 4 70 72 48.94 G C C

U1423B 6 H 5 70 72 50.94 G C F

U1423B 6 H 6 58 60 52.32 G C C R C

U1423B 7 H 2 140 142 56.60 G C F

U1423B 7 H 3 70 72 57.40 G A A

U1423B 7 H 4 70 72 58.90 G C C C F F

U1423B 7 H 5 70 72 60.40 G A A C C

U1423B 7 H 6 70 72 61.90 G A A A F

U1423B 8 H 3 70 72 67.09 G A

U1423B 8 H 4 70 72 68.59 M C P

U1423B 8 H 5 70 72 70.09 P R P

U1423B 8 H 6 70 72 71.59 G M

U1423B 9 H 3 70 72 77.11 G A R P

U1423B 9 H 4 70 72 78.61 M A F P P

U1423B 9 H 5 70 72 80.11 G A F R

U1423B 9 H 6 70 72 81.61 P R

U1423B 10 H 3 70 72 87.31 P R A

U1423B 10 H 4 74 76 88.85 P R F

U1423B 10 H 5 70 72 90.31 M C A

U1423B 10 H 6 30 32 91.41 P C P

U1423B 22 H CC 0 5 199.34 G A A P P A

U1423B 23 H CC 0 5 209.20 G A C P A

U1423B 24 H 4 140 142 215.12 M C F C

U1423B 24 H 6 70 72 217.42 M C C A

U1423B 24 H CC 0 5 218.86 G A R A P A

U1423B 25 H 2 70 72 220.92 M C F A

U1423B 25 H 4 70 72 223.92 M C F A

U1423B 25 H 6 70 72 226.92 M C F A

U1423B 25 H CC 0 5 228.17 G A R C R A

U1423B 26 H 2 70 72 230.42 M C F F C

U1423B 26 H 4 70 72 233.42 G C F A

U1423B 26 H 6 70 72 236.42 G C F C

U1423B 26 H CC 0 5 237.72 G A F C R F

U1423B 27 H 2 70 72 239.92 G A R F F

U1423B 27 H 4 70 72 242.92 G A F P F

U1423B 27 H 6 70 72 245.92 G A F R

U1423B 27 H CC 0 5 247.34 G A P C R F

U1423B 28 H 2 70 72 249.42 G A F R

U1423B 28 H 4 70 72 252.42 M A F

U1423B 28 H 6 70 72 255.42 G A P R

U1423B 28 H CC 0 5 256.92 G A P C F R

No. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19H

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U1425B 1 H 4 68 70 5.18 M R A

U1425B 1 H 5 98 100 6.98 M A C F C

U1425B 1 H CC 0 5 8.70 P R F R F F

U1425B 2 H 5 64 66 16.00 G A A P

U1425B 2 H 5 70 72 16.06 M VR

U1425B 2 H CC 0 5 19.05 M R F F P F R P R

U1425B 3 H 4 51 53 24.89 M A C R R A

U1425B 3 H 4 68 70 25.06 M F

U1425B 3 H 5 112 114 27.00 M C A P F

U1425B 3 H CC 0 5 28.38 M C R P A

U1425B 4 H 5 68 70 36.58 M F A

U1425B 4 H 7 31 33 39.02 M C F F R

U1425B 4 H CC 0 5 39.39 G A R A F

U1425B 5 H 5 31 33 46.02 M A P F

U1425B 5 H 5 71 73 46.42 M F

U1425B 5 H 6 81 83 48.02 G A C R F F R

U1425B 5 H CC 0 5 49.25 G C R R

U1425B 6 H 2 61 63 53.01 G A A P

U1425B 6 H 3 111 113 55.01 G C F F P

U1425B 6 H 4 68 70 56.08 M F C

U1425B 6 H 5 11 13 57.01 G A R F R

U1425B 6 H CC 0 5 60.49 M C R

U1425B 7 H 5 71 73 67.69 M VR F A F R

U1425B 7 H 5 103 105 68.01 P C R R

U1425B 7 H CC 0 5 70.57 P R C F R P

U1425B 8 H 3 137 139 76.00 M A R A P A

U1425B 8 H 4 71 73 76.84 M F P A F R

U1425B 8 H 5 137 139 79.00 M A R A F C

U1425B 8 H 7 38 40 81.01 M A R F R F A

U1425B 8 H CC 0 5 81.19 M C R R R F F

U1425B 9 H 3 4 6 84.99 P R R

U1425B 9 H 3 71 73 85.66 M F F A F

U1425B 9 H 4 54 56 86.99 M A P R F R

U1425B 9 H CC 0 5 91.54 G A R P F C F

U1425B 10 H 5 71 73 95.78 M R P A P P

U1425B 10 H 5 93 95 96.00 G A A R R

U1425B 10 H CC 0 5 98.67 G A F C F R P

U1425B 11 H 4 70 72 104.59 M F A F

U1425B 11 H 5 61 63 106.00 G C C R R F

U1425B 11 H CC 0 5 108.90 G C R R C P R

U1425B 12 H CC 0 5 #N/A G A R C F C R

U1425B 13 X CC 0 5 111.38 G A F C C C F

U1425B 14 H 3 58 60 115.00 G A P A R R F

U1425B 14 H 4 70 72 116.65 M F F A F R

U1425B 14 H 5 55 57 118.00 G A R A F R F

U1425B 14 H 6 105 107 120.00 G A R C P R F

U1425B 14 H CC 0 5 121.03 G A R C R C F F

U1425B 15 H CC 0 3 120.92 G A P F F C P

U1425B 16 X CC 0 4 122.05 G A C A C R F

U1425B 17 H 2 123 125 124.99 G C A R R R

U1425B 17 H 3 70 72 125.96 M R A F P

U1425B 17 H CC 0 5 126.76 G A F R A R

U1425B 18 H CC 0 5 131.91 G A C C C

U1425B 19 H CC 0 6 136.84 G C P C F F C

U1425B 20 H CC 0 6 143.10 G C P C R F

U1425B 21 H 2 20 22 144.02 G A R A 2 P A

U1425B 21 H 4 19 21 147.01 G A R A 2 R R A

U1425B 21 H 6 19 21 150.01 G A A R A

U1425B 21 H CC 0 5 151.97 G A R C C A

U1425B 22 H 3 110 112 156.98 G A P C R A

U1425B 22 H 5 10 12 158.98 G A P C F A

U1425B 22 H CC 0 5 162.60 G A P F F P F

U1425B 23 H 3 129 131 167.01 G A C F F

U1425B 23 H 5 129 131 170.01 G A R A F P R

U1425B 23 H CC 0 5 172.33 G A R C F

U1425B 24 H 2 144 146 175.99 G A C F F

U1425B 24 H CC 0 5 182.78 G A R P F P R

U1425B 25 H 2 90 92 184.99 M A F A R R

U1425B 25 H 4 91 93 188.00 G A P A P F

U1425B 25 H 6 91 93 191.00 M A F A R F F

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U1425B 25 H CC 0 5 192.27 G A P C P F

U1425B 26 H CC 0 5 203.41 G A P C C F P

U1425B 27 H 4 27 29 207.00 G A C R A

U1425B 27 H 6 26 28 209.99 G A F C R A

U1425B 27 H CC 0 5 211.93 G C F F R F

U1425B 28 H 3 147 149 217.00 G A R A R A

U1425B 28 H CC 0 5 221.00 G R C R R R

U1425B 29 H 1 81 83 222.01 G A R C P A F R

U1425B 29 H 3 81 83 225.01 G A R C R A F F

U1425B 29 H 5 82 84 228.02 G A P A R A F F

U1425B 29 H CC 0 5 230.70 G A P C R A C

U1425B 30 H 3 31 33 233.00 G A R A F A R R

U1425B 30 H 5 31 33 236.00 G A C R A F P

U1425B 30 H CC 0 5 239.32 G A R A F R F

U1425B 32 X CC 0 5 244.29 G A A R F

U1425B 33 H 3 39 41 246.99 G A C P R R R

U1425B 33 H 4 89 91 248.99 G A A R R

U1425B 33 H 6 90 92 252.00 G A A R C R

U1425B 33 H CC 0 5 253.16 G A C F F F

U1425B 34 H 4 46 48 258.00 M A F R R

U1425B 34 H CC 0 6 262.64 M C A R F P

U1425B 35 H 3 47 49 266.00 M A A C F P F

U1425B 35 H 5 47 49 269.00 M A A C

U1425B 35 H CC 0 5 271.74 G A C F

U1425B 36 H CC 0 5 277.60 G A A

U1425B 37 H 1 128 130 279.00 M A A R R

U1425B 37 H CC 0 5 282.45 G C A P

U1425B 38 H 1 101 103 283.00 M A C C R P

U1425B 38 H CC 0 5 286.71 G A A F

U1425B 39 H 2 125 127 290.00 G A A R

U1425B 39 H CC 0 6 292.01 G A A F

U1425B 40 X 1 109 111 293.00 M C R R

U1425B 40 X 3 9 11 295.00 M A C R

U1425B 40 X CC 0 5 297.05 G A A P

U1425B 41 H CC 0 5 301.38 G A A F

U1425B 42 H CC 0 5 307.10 G A A P

U1425B 43 H CC 0 5 311.82 G A A P

U1425B 44 H 4 4 6 316.00 G A C F

U1425B 44 H CC 0 5 316.51 G A A F

U1425B 45 H CC 0 5 320.57 G A A F

U1425B 46 H CC 0 5 325.22 M A C C

U1425B 47 H 1 91 93 326.01 G A A F

U1425B 47 H 3 91 93 329.01 G A A P

U1425B 47 H CC 0 5 329.81 G F P

U1425B 48 H CC 0 5 335.55 G F F F

U1425B 49 H 2 129 131 339.01 G A A P P

U1425B 49 H CC 0 5 340.94 G F C

U1425B 50 H 2 66 68 343.98 G A C F C

U1425B 50 H 3 117 119 345.99 M A A R F

U1425B 50 H CC 0 5 346.57 G A A P

U1425B 51 H CC 0 5 352.15 M C A F P

U1425B 52 H CC 0 5 356.82 M C A P R

U1425B 53 H CC 0 5 361.58 M C F F C

U1425B 54 H CC 0 5 366.18 P R F P P

U1425B 55 X CC 0 5 375.41 P R P F

U1425B 56 X CC 0 5 381.25 P R F P

U1425B 57 X CC 0 5 384.60 P VR

U1425B 58 X CC 0 5 393.63 P VR

U1425B 59 X CC 0 2 409.94 B

U1425B 60 H CC 0 5 417.66 M R P F P

U1425B 61 X CC 0 4 419.15 P R

U1425D 57 H CC 0 5 390.86 P R R F F

U1425D 58 H CC 0 5 394.93 P R R

U1425D 59 H CC 0 5 399.77 P R P C C

U1425D 60 H CC 0 5 404.41 P R P P

U1425D 61 H CC 0 5 405.82 P R A F C

U1425D 62 H CC 0 5 408.67 P VR C C

U1425D 63 H CC 0 5 413.06 P VR P R P

U1425D 64 H CC 0 5 416.41 P VR A P

U1425D 65 H CC 0 5 419.82 P R C R

U1425D 66 H CC 0 5 423.42 P R

U1425D 67 H CC 0 5 424.26 P VR F P

U1425D 69 H CC 0 5 429.40 P VR

U1425D 70 H CC 0 1 430.40 B

No. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26H

ole

Core

Typ

e

Sec.

Inte

rval

Top

(cm

)

Inte

rval

Bot

tom

(cm

)

CC

SF-A

(m

)

PR

ESER

VA

TIO

N

AB

UN

DA

NC

E

Am

phim

elis

sa s

etos

a

Axo

prun

um a

cqui

loni

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Cal

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mot

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ana

Cyc

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psel

la ja

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Cyr

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psel

la t

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Dic

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Den

dros

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Den

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Hex

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Lip

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Lip

man

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Litho

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Lyc

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corn

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Sip

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ara

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a gr

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Sch

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s jo

poni

scus

Sty

losp

haer

a m

agna

poru

losa

U1430A 1 H CC 3.74 P R F R

U1430A 2 H 4 68 70 9.14 P vR R R

U1430A 2 H CC 13.63 P R R

U1430A 3 H 4 68 70 19.28 M F R R

U1430A 3 H CC 23.88 G A C F

U1430A 4 H 4 68 70 29.59 M F C

U1430A 4 H CC 33.99 G A R A

U1430A 5 H 4 68 70 39.23 G F R R R

U1430A 5 H CC 44.00 G F F R

U1430A 6 H 4 68 70 49.15 M F R R

U1430A 6 H CC 53.74 G A F C

U1430A 7 H 4 68 70 59.20 G F R R F R

U1430A 7 H CC 63.92 G F R F R R F

U1430A 8 H 4 68 70 69.22 M F R R R F R

U1430A 8 H CC 73.83 G C F C R F C

U1430A 9 H 1 68 70 74.33 G F R C C

U1430A 9 H 2 68 70 75.83 G F R C R C

U1430A 9 H 3 68 70 77.33 G F R F F

U1430A 9 H 4 8 10 78.23 G C R F R

U1430A 9 H 4 68 70 78.83 G F R F R

U1430A 9 H 4 120 122 79.35 G F R F R R

U1430A 9 H 5 11 13 79.76 G F R C R R

U1430A 9 H 5 70 72 80.35 G C C R

U1430A 9 H 6 70 72 81.85 G F R C

U1430A 9 H CC 83.45 G C F C F

U1430A 10 H 1 70 72 84.75 G F F C

U1430A 10 H 2 70 72 86.25 G F F C R

U1430A 10 H 3 68 70 87.73 G F F F R

U1430A 10 H 4 68 70 89.23 G F F R

U1430A 10 H 5 70 72 90.75 G F F R

U1430A 10 H 6 70 72 92.25 G F F R

U1430A 10 H CC 93.91 G C C F

U1430A 11 H 4 68 70 99.35 G F F R

U1430A 11 H CC 103.91 G F A R R

U1430A 12 H 4 68 70 109.56 G F C R

U1430A 12 H CC 114.19 G F A R R

U1430A 13 H 4 68 70 119.82 G F F

U1430A 13 H CC 124.47 G C A R R

U1430A 14 H 4 68 70 129.73 G R C

U1430A 14 H CC 134.37 G C A F F

U1430A 15 H 4 68 70 139.65 G C C R

U1430A 15 H CC 144.28 G A A R F

U1430A 16 H 1 70 72 145.44 G F R

U1430A 16 H 2 70 72 146.94 G F R R

U1430A 16 H 3 70 72 148.44 G F R

U1430A 16 H 4 70 72 149.94 G F R

U1430A 16 H 5 68 70 151.42 G F R R R

U1430A 16 H 6 70 72 152.94 G F F R

U1430A 16 H CC 154.61 G C F F R

U1430A 17 H 1 70 72 156.81 M F R R R

U1430A 17 H 2 70 72 158.31 G F F R

U1430A 17 H 3 68 70 159.79 G C C R

U1430A 17 H 4 70 72 161.33 G F C R

U1430A 17 H 5 68 70 162.83 G R A

U1430A 17 H 6 70 72 164.33 G F A

U1430A 17 H CC 165.97 G C A

U1430A 18 H 4 68 70 170.59 G F F

U1430A 18 H CC 175.25 G F A R R R

U1430A 19 H 4 70 72 180.94 M F F R

U1430A 19 H CC 185.60 G F F C F

U1430A 20 H 4 68 70 191.06 M R F

U1430A 20 H CC 194.76 G C F R F

U1430A 21 H 4 68 70 200.65 M R R

U1430A 21 H CC 204.87 M C F

U1430A 22 H 4 68 70 211.39 G F R

U1430A 22 H CC 215.41 G C R R F F

U1430A 23 H 4 68 70 220.91 M F R R F

U1430A 23 H CC 225.34 G C R F F

U1430A 24 H 4 68 70 230.83 H F R F

U1430A 24 H CC 235.36 G C R F R

U1430A 25 H 1 70 72 235.61 M F R R

U1430A 25 H 2 70 72 237.11 G F R R

U1430A 25 H 3 70 72 238.61 G R R R

U1430A 25 H 4 70 72 240.11 G R R R

U1430A 25 H 5 68 70 241.59 G R F R R

No. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26H

ole

Core

Typ

e

Sec.

Inte

rval

Top

(cm

)

Inte

rval

Bot

tom

(cm

)

CC

SF-A

(m

)

PR

ESER

VA

TIO

N

AB

UN

DA

NC

E

Am

phim

elis

sa s

etos

a

Axo

prun

um a

cqui

loni

um

Cal

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las

mot

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ana

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a gr

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Sch

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s jo

poni

scus

Sty

losp

haer

a m

agna

poru

losa

U1430A 25 H 6 70 72 243.11 G R F

U1430A 25 H CC 244.40 M C C F R

U1430A 26 H 1 70 72 246.00 M R F R R

U1430A 26 H 2 68 70 247.48 M F R R

U1430A 26 H 3 70 72 249.00 M R F

U1430A 26 H CC 250.24 M C F C

U1430A 27 H 3 68 70 253.69 G F F

U1430A 27 H CC 254.99 G A F C C R

U1430A 28 H 1 70 72 255.99 M R F R R

U1430A 28 H 3 25 27 258.56 P R R R R

U1430A 28 H CC 260.25 M A R R C R

U1430A 29 H CC 264.63 P F R R C A

U1430A 30 X CC 264.63 P R C R

U1430A 31 X CC 3 5 270.16 P R R R R R

U1430A 32 X CC 280.33 B B

U1430C 29 H CC 254.36 M C R R F

U1430C 30 H CC 259.30 M F R R

U1430C 31 H CC 260.69 P R C R F

U1430C 32 H CC 265.32 P R C F

U1430B 32 H 1 111 113 267.45 P F C R

U1430B 33 X 1 59 61 272.63 P C F

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