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Geochemical Study on the Origin of Organic Matter and Depositional Environment of Late Quaternary
Sediments in the Ulleung Basin of the East Sea*
Myong-Ho Park1, Ji-Hoon Kim2, and Gee-Soo Kong2
Search and Discovery Article #10672 (2014)**
Posted November 24, 2014
*Adapted from poster presentation given at AAPG International Conference & Exhibition, Istanbul, Turkey, September 14-17, 2014
**Datapages © 2014 Serial rights given by author. For all other rights contact author directly.
1
E&P Technology Institute, Korea National Oil Corporation, Anyang, Republic of Korea (myongho@knoc.co.kr)
Petroleum and Marine Research Division, Korea Institute of Geoscience and Mineral Resources, Daejeon, Korea, Republic of Korea
2
Abstract
According to radiocarbon dating of planktonic foraminifera samples from the Ulleung Basin of the East Sea, the cores cover the time interval
from the middle stage of marine isotope stage (MIS) III through the last glacial maximum (LGM) to the Holocene. In the cores, hemipelagic
muds (bioturbated and slightly laminated mud facies) were mainly deposited during interglacial periods (MIS I/III), whereas non-hemipelagic
muds (laminated and homogenous mud facies) were formed during glacial period (MIS II). During the cold time, sedimentation rates clearly
increased more than the other times. Such characteristic changes in sedimentary facies and sedimentation rate evidently reflect paleoenvironmental variations on the Ulleung Basin during the Late Quaternary. Also, the cores contain several lapilli tephra layers, rhyolitic ash
layers, and dark laminated muds. Among these, previously well-known tephra layers (Ulleung-Oki, Aira-Tanzawa, and Ulleung-Yamato) were
identified and used to stratigraphically correlate the cores. Particularly, our sedimentary geochemical studies (Rock-Eval pyrolysis, elemental,
and stable isotope analyses) allow us to discuss the origin of organic matter and the depositional environment of sediments. Down-core profiles
of TOC (Total Organic Carbon), TN (Total Nitrogen) and δ13Corg show the lowest values during MIS II and the highest during MIS I. The
relationship between TOC/TN and δ13Corg suggests that the organic matter was predominantly produced by a marine source rather than by a
terrestrial source. However, redox-sensitive trace elements have not significantly varied during MIS II as well as during MIS I/III. The ratios of
these trace elements also indicate a predominant oxic or suboxic environment, indicating that the Late Quaternary depositional condition of the
Ulleung Basin was less dynamically changed than we expected before.
References Cited
Kim, J.H., M.H. Park, U. Tsunogai, T.J. Cheong, B.J. Ryu, Y.J. Lee, H.C. Han, J.H. Oh, and H.W. Chang, 2007. Geochemical characterization
of the organic matter, pore water constituents, and shallow methane gas in the eastern part of the Ulleung Basin, East Sea (Japan Sea): Island
Arc, v. 16, p. 93–104.
Park, M.H., J.H. Kim, B.J. Ryu, I.S. Kim, and H.W. Chang, 2006, AMS radiocarbon dating of the marine late Pleistocene-Holocene sediment
cores from the Ulleung Basin, East/Japan Sea: Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions and
Materials and Atoms, v. 243, p. 211–215.
Park, M.H., I.S. Kim, and J.B. Shin, 2003, Characteristics of the late Quaternary tephra layers in the East/Japan Sea and their new occurrences
in western Ulleung Basin sediments: Marine Geology, v. 202/3–4, p. 135–142.
Sept. 14~17 / Istanbul / Turkey
Geochemical Study on the Origin of Organic Matter and
Depositional Environment of Late Quaternary Sediments
in the Ulleung Basin of the East Sea
1
2
M.H. Park , J.H. Kim , and G.S. Kong
2
1
E&P Technology Institute, Korea National Oil Corporation , Korea Institute of Geoscience and Mineral Resources
Abstract
Type of Tephras
o
135 E
140 E
o
44 N
2 0 00
B
E a st S ea
2 00 0
1 00 0
o
40 N
30
Origin and Diagenesis of Organic Matter
A
00
20
B
0.75
B
00
10
2 00
OB
UB
MIS II
Japan
08HZP-01 (Terrigeneous)
0.50
TN (wt%)
08HZP-01 (Marine)
Ko rea Strait
(d ep th 1 4 0 m)
B
G
UI
KP
UBGH2-1_1
UBGH2-2_1
UBGH2-5
Ulleun g
Is.
C
-20
-25
C3 Land Plants
0.25
15.4
0.95
1.02
1.57
AT
23.0
2.34
2.45
2.66
U-Ym
30.9
-
4.78
5.79
5.22
5.44
7.34
35 N
(DLM, Dark laminated mud; U-Oki, Ulleung-Oki layer; AT, Aira-Tanzawa layer; UYm, Ulleung-Yamato layer)
3
HM
4
5
LM
SLM
HM
LM
BM
FO
SLM
HM
SLM
HM
SLM
BM
MIS 3
BM
4
5
MS G
SLM
BM
BM
SLM
BM
BM
HM
HM
FO
FO
HM
HM
3
MIS 1
OB
0
2
6
0
10
20
HM
BM
HM
LM
FO
BM
LM
5
BM
BM
6
MIS 3
30
TOC
8
Downcore profiles of TOC/TN,
δ13Corg and δ15Norg
15.9 cm/kyr
Depositional Condition : Influence of Tephra and
Biodetritus
6
20.7 cm/kyr
23.1 cm/kyr
MIS 2
MIS 3
8
MIS 1
 Abundance of redox-sensitive trace elements (e.g., Mn, V, U, and Mo) : Not varied from MIS 3
to MIS 1
Relationship between the depths
and calibrated ages
Characteristic Change in
Sedimentary Facies
 Ratios of redox-sensitive trace elements indicate a predominately oxic or suboxic
environment during times of sediment deposition since the Late Quaternary
 Tephra and foraminiferal shell fragments display abnormal element/Al ratios : Biodetritus and
tephra obviously affect the variation of sedimentary facies and the geochemistry in the
Ulleung Basin
Oxic
A
Suboxic
Anoxic
3
4
1
1
1
1
0.5
0
0
0
0
SLM AL
AL
BM
BM U-Ym
SLM
 Volcanic layers and grains are found in all
cores. In particular, the U-Oki, AT and U-Ym
layers are easily identified; the massive-type
glass shards of the lapilli layers correspond to
the U-Oki and U-Ym tephra layers, whereas the
bubble-well and/or plane-type glass shards are
the AT ash layer
Suboxic
2
2
MIS I
MIS II
MIS III
KCES-1
0.6
0
0.4
0
2
4
6
8
10
0
0.5
1
1.5
18
60
1
1
12
40
0.5
0.5
6
20
0
0
0
0
MIS I MIS II MIS III
MIS I MIS II MIS III
1.5
2
2.5
3
U/Th
Ni/Co
1.5
Anoxic
0.8
V/Cr
2
Co EF
2
Suboxic
1
1.5
CuEF
 In the cores, hemipelagic muds (bioturbated
and slightly laminated mud facies) were mainly
formed during interglacial periods (MIS 1 / MIS
3), whereas non-hemipelagic muds (laminated
and homogenous mud facies) were deposited
glacial period (MIS 2)
3
Oxic
B
6
Correlation (A) between V/Cr and Ni/Co and (B)
between V/(V+Ni) and U/Th
BM
MS G
BM : Bioturbated mud
LM : Laminated mud
SLM : Slightly laminated mud
HM : Homogenous mud
FO : Foraminiferal ooze
AL : Ash layer
TL : Lapilli (tephra) layer
U-Ok i : Ulleung-Oki layer
U-Y m : Ulleung-Yamato layer
AT : Aira-Tanzawa layer
DLM : Dark laminated mud layer
MIS : Marine Isotope Stage
BM
SLM DLM
HM
FO
HM
LM
SLM FO
HM
BM
BM
AT(?)
HM
AL
HM
SLM AL
AL
4
4
U-Oki
HM
SLM
SLM
BM
MIS 1
Oxic
AT
BM
SLM BM
SLM
FO FO
SLM
BM AL
BM LM
HM
BM FO
HM
U-Ym
BM (30.9
ka)
BM
HM
40
VEF
2
0
MoEF
3
SLM LM
BM
30
3
SLM
4.5
UEF
HM
3
NiEF
HM
HM
Slumped Sandy M
1
MIS 3
4
 The decreasing downcore profile of nitrate concentration, the increasing downcore profile of
phosphate concentration, and lower N/P ratio (<12.4) in the water column: Evidence of the
occurrence of denitrification via micro-reducing environment or aerobic denitrification in the
sea
MnEF
2
BM
DLM
HM
HM
SLM
SLM
TL
MIS 2
MIS 2
1
U-Oki
HM
MIS 3
2
DLM
SLM (15.4
ka)
SLM HM
SLM
HM
SLM
HM
SLM HM
SLM
LM
HM
HM
AT
HM (23.0 ka)
HM
SLM
BM
SLM
SLM
HM
SLM
SLM
HM
SLM
HM
SLM
SLM
HM
BM
MIS 1
BM
BM
1
0
(m)
HM
MIS 2
0
(m)
MIS 3
U-Oki
HM (10.1
ka)
SLM
MIS 1
BM
03GHP-04
20
03GHP-02
03GHP-03
03GHP-04
Depth (mbsf)
 Selected samples were 14C-dated by AMS at the lab. of Univ.
Kiel, Germany
 After tephrostratigraphic studies, DLM, U-Oki, AT, and U-Ym
represent 15.4, 10.1, 23.0 and 30.9 ka BP, respectively (e.g.,
Park et al., 2006; Kim et al., 2007). They are useful tie points
for the chronostratigraphic correlation, and were here used
to construct the age model of the sediment cores
 According to this method, the U-Oki layer is roughly
designated as the boundary between MIS 1/2 and the AT
layer is between MIS 2/3
10
2
 Enriched δ15Norg : Usually caused by the denitrification process in the water column under
suboxic condition
o
132 E
A g e (k y r)
0
MIS 1
an
Ulleung Basin in the East Sea
and core location
Age Dating and Model
0
(m)
p
Ja
o
o
0
 δ15Norg : 4 ~ 11 ‰
→ Originated from marine algae
KCES-1
130 E
1.5
TOC (wt%)
20 0
* - : no observation
03GHP-03
UBGH2-1_1
0
CrEF
Length (m)
Depth of three
tephras and DLM
layers in the
cores
20 0 0
MIS 3
4
Anoxic
DLM
UB
2
Oxic/Suboxic
1.00
MIS 1
V/ (V+Ni)
0.49
12
Anoxic
0.32
9
6
50 0
10.1
HB
U-Oki
UBGH2-2_1
03GHP-03
UBGH2-5
03GHP-02
08HZP-01
10 0 0
03GHP-04
6
-35
0.00
Korea
03GHP-03
Freshwater
algae
4
03GHP-02
3
MIS 2
2 2 00
37o N
20 -28 -26 -24 -22 -20 0
2
Dok
Is.
15 0 0
Cal Age (ka BP)
03GHP-04
15
6
-30
Depth (mbsf)
10
C4 Land
Plants
Marine
algae
-15
MIS III
00
10 0
20
5
MIS 2
-10
MIS I
0
6
3 00 0
YB
0
15Norg ‰

MIS 2
 Correlation between TN and TOC and between δ13Corg and
TOC/TN
→ Most organic matter has been located in or near the region
of marine algae since MIS 3
20
36o N
A
YR
00
13Corg ‰

TOC/TN
 TOC/TN ratios : 6 ~ 10 and δ13Corg : -21 ~ -28 ‰
→ Organic matter is predominantly generated by marine
algae rather than by terrestrial plants
→ and has not significantly changed since MIS 3 in the basin
00
KP
Korea
 To present the stratigraphic age dating and characteristic
sedimentary facies of samples taken from the Ulleung Basin
of the East Sea
 To identify the source of organic matter, and then, to
reconstruct the depositional environment of sediment since
Marine Isotope Stage (MIS) 3
 Piston cores were taken from the central Ulleung Basin part
during the R/V Tamhae II cruise of KIGAM for the Gas
Hydrate R&D Project
ES
0
300
Tsug aru Strait
(dep th 1 30 m)
20 0 0
1 00
(Park et al., 2003)
Depth (mbsf)
Purposes of Study and Materials
130 E
o
Japanese origin (AT)
 Japanese origin (AT)
→ Plane-type and/or bubble-wall shards
→ K-poor glasses (R=ca. 0.04) and
rhyolitic composition
13Corg ‰

A
o
 Ulleung origin (U-Oki and U-Ym)
→ Pumice-type glass shards
→ K-rich glasses (R=K2O/SiO2>0.09)
ranging from phonolitic to trachytic
alkali compositions
Depth (mbsf)
Particularly, our sedimentary geochemical studies (Rock-Eval pyrolysis, elemental and stable
isotope analyses) allow us to discuss the origin of organic matter and the depositional environment
of sediments. Down-core profiles of TOC (Total Organic Carbon), TN (Total Nitrogen) and δ13Corg
show the lowest values during MIS 2 and the highest during MIS 1. The relationship between
TOC/TN and δ13Corg suggests that the organic matter was predominantly produced by a marine
source rather than by a terrestrial source. However, redox-sensitive trace elements have not
significantly varied during MIS 2 as well as during MIS 1/3. The ratios of these trace elements also
indicate a predominant oxic or suboxic environment, indicating that the Late Quaternary
depositional condition of the Ulleung Basin was less dynamically changed than we expected before.
Ulleung origin (U-Oki & U-Ym)
Depth (mbsf)
According to radiocarbon dating of planktonic foraminifera samples from the Ulleung Basin of
the East Sea, the cores cover the time interval from the middle stage of marine isotope stage (MIS)
3 through last glacial maximum (LGM) to Holocene. In the cores, hemipelagic muds (bioturbated
and slightly laminated mud facies) were mainly deposited during interglacial periods (MIS 1/3),
whereas non-hemipelagic muds (laminated and homogenous mud facies) were formed during
glacial period (MIS 2). During the cold time, sedimentation rates clearly increased more than the
other times. Such characteristic changes in sedimentary facies and sedimentation rate evidently
reflect paleo-environmental variations on the Ulleung Basin during Late Quaternary. Also, the
cores contain several lapilli tephra layers, rhyolitic ash layers and dark laminated muds. Among
these, previously well-known tephra layers (Ulleung-Oki, Aira-Tanzawa and Ulleung-Yamato) were
identified and used to stratigraphically correlate the cores.
03GHP-02
2
MIS I MIS II MIS III
Box plots for EF values of Mn, V, Cu, Co, Cr, Ni, U, and Mo
MIS I MIS II MIS III
※ Enrichment Factors (EFs), XEF = (X/Al)sample/(X/Al)AS
Acknowledgements:
BM
BM
7
FO
BM
Lithology of core sediment and inferred stratigraphy correlation
based on tephra and DLM layers (mbsf, meters below sea floor)
This work was supported by the projects “Construction of carbon storage map and selection of demonstration sites
in Korean offshore areas” (20052004) and “ Small-scale CO2 injection-demonstration project in offshore Pohang
Basin” (20132010201760).
MS G
myongho@knoc.co.kr