Previous Work: Sediments cored trench-side of the Kurile Arc (refer to DSDP/ODP maps)
note: according to HS2-NUVEL1 Absolute Plate Motion Model (Gripp and Gordon, 1990)
(http://triton.ori.u-tokyo.ac.jp/~intridge/pmc/hs2_nuvel1.html), plate motion is 10cm/yr @ 300 deg
Site 193 (DSDP Leg 19; 1973):
from the IR:
cores 1 (0-2m, 100% recovery) and 2 (2-11m, 33%):
glass-bearing (vitric ash) diatomaceous silty clays and clayey diatom oozes. Pebbles of sedimentary rock (glacial
erratcs), clay balls, and crystal and vitirc ash are common.
cores 3 (25-34m, 81%) and 4 (62-71m, only CC recovered): diatom and glass-rich silty clays.
note: drilling at Site 193 was shortened due to a medical emergency; only 71m drilled.
Role of subducted sediments in the genesis of Kurile-Kamchatka island arc basalts; Sr isotopic
and elemental evidence
Author: Bailey, John C.
Series/Source: Geochemical Journal
30, no. 5 (1996): 289-321
abbrev abstract:
87Sr/86Sr ratios of ocean floor sediments for the NW Pacific result from mixing between island arc detritus (0.7037)
and open ocean detritus derived from the upper cont. crust (0.7175). A simple mechanical addition of any type or mixture of
known sediments to the sub-arc mantle fails to reproduce the overall geochemistry of the arc basalt and selective transfer of
mobile elements (Cs, Rb, K, Ba, Sr) and low 87Sr/86Sr component (altered MORB [fluid?], sub-arc mantle) seem required.
Geochemical history of sediments in the northwestern Pacific Ocean
Author: Bailey, John C.
Series/Source: Geochemical Journal
27, no. 2 (1993): 71-90
abbrev abstract:
NW Pacific surface sediments are dominantly detrital with lesser amounts of biosiliceous and hydrogenous material.
The detrital components change regularly from trench sediments dominated by island-arc volcaniclatic debris to open ocean
sediments with higher REE, Th, Rb, Cs, La/YbN, La/Sc, and Th/Hf but lower Eu/Eu*, Co/Th, K/Rb and Rb/Cs. The open ocean
sediments are dominated by upper cont. crustal debris. Buried sediments from DSDP holes pass through a 3-stage evolution:
ocean-ridge basaltic debris and hydrothermal precipitates, abyssal plain sediments characterized by hydrogenous material
and upper cont. crustal debris, and near-shore island-arc detritus with intermittent air-fall ash. Biogenic and within-plate
basaltic/hydrothermal components cause important local deviations from this evolution.
Sites 303, 304 (DSDP Leg 32; 1975):
from the IR:
Holes 303, 303A:
Unit 1 (~183m, ~80% recovery; sedimentation rate from middle Miocene to late Pleistocene ~16m/My): diatom-rich
radiolarian ooze (siliceous fossil remains), commonly rich in volcanic ash and grading down to raliolarian-bearing pelagic
clay. Angular quartz and mica grains (may be wind transported), abundant in XRD analysis, are suggestive of terrestrial
component. Volcanogenic component generally glass (or sometimes feldspar) grains.
Unit 2 (~45m, very poor recovery due to chert, <5%, sed rate ~0.4m/My): zeolitic pelagic clay and chert. Appears
to grade down from Unit 1 (e.g., dissolution of radiolaria). Clay is generally very zeolitic; also contains amorphous iron oxide,
finely dispersed or concentrated in microscopic aggregates, and minor volcanic glass.
Unit 3 (<20m, ~5%, sed rate ~0.4m/My): clayey nanno ooze and chert. Containing clay minerals, zeolites, glass
shards, chert fragments, and amorphous iron oxide.
Hole 304:
Unit 1 (9.5m, 58% recovery, sed rate ~16m/My): radiolarian-diatom ooze
Unit 2 (~100m; 100% (top)-<3% (bottom) recovery, sed rate ~16m/My): unfossiliferous brown pelagic clay with
thin interbeds of pale orange volcanic ash grading to a zeolitic pelagic clay, with chert appearing, and becoming dominant,
downhole. Sedimentation rate of pelagic clays may suggest that they are not abyssal clay facies, which typically have rates
~an order of magnitude less.
Unit 3 (~15m, <3%): nanno ooze and chert
Interpretation of sedimentation and tectonic evolution of the sediments (IR, pp925-8):
Sedimentation history starts with the deposition during Hauterivian to Barremian times of carbonates with lesser
amounts of siliceous organisms (converted to chert). This may represent ridge-flank sedimentation; this first stage is
represented by only a relatively thin layer, suggesting that the sites subsided below the CCD rather soon (deep ridge crest?).
The sites reached the equatorial zone after sinking below the CCD, and the crossing of that high productivity zone during the
Aptian-Cenomanian is characterized by the deposition of abundant siliceous organisms (which were subsequently
diagenetically recrystallized into chert). The transition between ridge-flank carbonate sediments and siliceous equatorial
deposits is characterized by a gradual upward decrease in the amount of carbonate while the chert becomes progressively
more abundant. The increase in chert does not seem to be due to the decreasing dilution by carbonate components as the
rate of sedimentation remains constant during the facies change. After leaving the equatorial zone, the sites transited (during
the entire late Cretaceous, Paleogene, and the lowermost Neogene) across the vast low productivity areas that characterize
the mid-latitude North Pacific, e.g., the deposition of a thin layer of deep-sea pelagic clay at a low rate of sedimentation
(sedimentation hiatuses are not excluded). At about the middle to late Miocene, the sites reached the NW Pacific zone of high
productivity associated with the Kuroshio Extension Current, leading to a rapid accummulation of radiolarian and diatom ooze
that represents the upper half of the sedimentary section at both sites. The uppermost section of Site 303 shows an upward
grdual increase in the amount of volcanic ash (from the incoming Japan/Kuril volcanic arcs).
Site 580, 581 (DSDP Leg 86; 1984):
from the IR vol:
sediments from sites 580 (similar to 579) and 581 are used to make a composite of the entire sed pile off the Kuril arc.
Site 580:
Subunit 1A (~60m, >80% recovery): siliceous clay w/ 2-20% diatoms, 0-15% rads, 3-15% qtz, feldspar and heavy
minerals <2%, volcanic glass (excluding ash layers) 2-10%, clay ~56%; 43 ash layers ID.
Subunit 1B (~20m, ~85%): calcareous siliceous clay w/ 3-25% unspecified clay-sized carbonate materail, 10-25%
diatoms, 5-7% rads, 5-10% qtz, feldspar <2%, dispersed ash 3-7%, ~55% clay; 7 ash layers.
Subunit 1C (~35m, >85%): siliceous clay similar to subunit 1A; 18 ash layers.
Subunit 1D (~20m, ~90%): clayey diatom ooze w/ 50-60% diatoms, 2-10% rads, 5-10% qtz, feldspar 2%, dispersed
volcanic ash 5-10%, 27% clay; 7 ash layers.
Subunit 1E (~20m, ~85%): siliceous clay, slightly enriched in siliceous microfossils compared to 1A/C. Ave
compositions are 27% diatoms, 8% rads, rare to absent feldspar, 7% qtz, dispersed volcanic glass 2-10%, 53% clay; 14 ash
layers.
Quaternary through late Pliocene sedimentation rate nearly constant ~50m/My. Throughout Site 580 (and 579) are a large
number of thin, stiff to indurated, dark greenish (pyritic) gray layers that are composed of the same material as adjacent
sediment.
Site 581:
cored 0-1 mbsf --> washout to ~180mbsf --> cored ~180mbsf - basalt
Unit 1: biogenic siliceous clay
Subunit 1A (~42m, including 0-1m and 181-223m): dark gray to greenish gray biosiliceous clay; 20-60%
diatoms, 5-15% rads are the primary biosiliceous components w/ 0-2% silicoflagellates; clay 30-65% and qtz 3-5% constitue
the terrigenous component. Volcanic glass <5%; 4 ash layers; much fewer layers of the indurated dark greenish gray layers.
Subunit 1B (~20m): light yellowish brown to yellowish brown biosiliceous clay; 7-20% diatoms, 7-20%
rads, tr-5% silicoflagellates, 65085% clay, 3-5% qtz, <2% dispersed volcanic glass; only 1 ash layer.
Unit 2 (~32m): pelagic brown clay; brown to dark brown nonbiogenic clay, sometimes mottled; >90% clay, biogenic
siliceous material is absent, 2-3% qtz, 0-3% volcanic glass, 0-3% opaques, 0-7% micronodules.
Unit 3 (~66m, <~10%): grayish and yellowish brown to yellow red, pink, reddish black, and black chert with qtz veins
and layers of porcellanite in the larger grains. Drill ops suggest chert layers (few cm) separated by (tens of cm) soft sed not
recovered.
Sedimentation rates range from ~5m/My in the late Miocene to ~40m/My in the Plio-Pleistocene (but missing ~1-180mbsf).
Geochemistry of sediments at Sites 579, 580, 581 DSDP Leg 86, Western North Pacific
Author: Heath, Kovar, and Lopez
Initial Reports of the Deep Sea Drilling Project
86 (198511): 657-670
abrev. abstract:
The elemental composition of sediments from Site 579 and 580 is dominated by contributions from terrigenous
detritus (including numerous thin ash beds) and opal-rich biogenic debris, with the terrigenous component increasing in
dominance in the youngest sediments as the flux of Pleistocene eolian debris associated with Northern Hemisphere glaciation
increased. Diagenesis related to redox-sensitive reactions in near-surface sediments has had a marked impact on the
distributions of Mn and S.
At Site 581, the reduced biosiliceous clays corresponding to the section at Sites 579 and 580 are underlain by a
normal oxidized North Pacific “red clay” sequence. As at other North Pacific sites, the concentrations of Mn and Fe (as
oxyhydroxides), Ba (barite), and P (fish debris) vary inversely with the accumulation rates of the clays. The cherts underlying
the clays at Site 581 are noteworthy for their high P contents (comparable to values of the clays) and high Fe and Mn relative
to Ti and Al, suggestive of derivation from well-oxidized pelagic sediments.
note: analyzed Mn, Fe, Si, Al, K, Ca, Mg, Ti, P, Ba, S by XRF
Pb isotope composition of Klyuchevskoy Volcano, Kamchatka and North Pacific sediments;
implications for magma genesis and crustal recycling in the Kamchatkan arc
see below, Site 881
10
Be distributions in Deep Sea Drilling Project Site 576 and Site 578 sediments studied by
accelerator mass spectrometry
Ku, T. L.; Southon, J. R.; Vogel, J. S., and others
Initial Reports of the Deep Sea Drilling Project
86 (198511): 539-546
abbrev abstract:
Extension of the 10Be geochronology for deep-sea sediments beyond the limit of late Pliocene age found in published
works has been attempted. The results obtained on sediments from DSDP Sites 576 and 578 of Leg 86 suggest the feasibility
of dating sediments as old as 12-15Ma. At both sites, there have been large changes in sedimentation rate, with the
Oleistocene sediments accumulating several times faster than those of the Pliocene, which in turn were deposited several
times more rapidly than the late Miocene sediments. The Pleiostocene-Pliocene section is considerably thicker in Hole 578
than Hole 576B: the respective depths for the 7Ma time boundary in the two holes are ~125 and ~25 m. These 10Be-based
age estimates are in agreement with the paleomagnetic stratigraphies for the two sites. The suggested enhancement in the
ocean deposition of 10Be before 7-9Ma, as noticed in Mn crusts, has found tentative support from the present sedimentary
records. A preliminary search for 10Be production variation during a geomagnetic field reversal has been constructed. In Hole
578, as enhanced 10Be concentration is found in a sample close to the Brunhes/Matuyama reversal boundary. More detailed
and systematic measurements are required to confirm this observation, which bears o the geomagnetic field during the
reversal.
Also used by DK Rea and LJ Ruff (EPSL 140, 1-12) to construct composite section for the NW Pacific
(combined N Japan and Kurile arcs): (mass %)
Japan/Kurile = 20% terrigenous, 13% carbonate, 12% opal, 55% seawater
[Site 881, included in Kamchatka = 11% terrigenous, 5% carbonate, 31% opal, 53% seawater]
Also used by Plank and Langmuir in constructing the GLOSS database; see attached table for average
geochemistry of 3 main lithologies and average bulk sediment off the Kurile trench.
Site 881 (ODP Leg 145):
Brief summary of sediment coring at Site 881:
One sedimentary unit with two subunits:
1A (0-164 mbsf) is a clayey diatom ooze of the late Pliocene and Pleistocene; includes IRD, ash layers, and dolomite
as concretions, burrow fill, and discrete layers. Over ~20m, 1A grades into 1B (164-364 mbsf), which is a radiolarian/diatom
ooze of latest Miocene to Pleistocene age. IRD, ash and dolomite occur, but in much lower amounts.
Generally, recovery was near 100% for subunit 1A (20-25% clay, 75-80% diatom ooze), near 100% for the top ~60m
of subunit 1B (100% diatom ooze), and <50% for the total remaining cored subunit 1B.
Sediments deposited at Site 881 since the late Miocene record interactions in the supply of biogenic silica,
terrigenous clastics, and continental volcanics to the NW Pacific Ocean. Subunit 1B has lower relative inputs of terrigenous
material volcanic ash layers and a lower overall sedimentation rate; dropstones first appear ~243 mbsf, ~4Ma within subunit
1B. Subunit 1A (~164 mbsf, ~2.6 Ma) contains more dropstones, fine-grained (hemipelagic) terrigenous material, and volcanic
ash than the underlying diatomaceous oozes, suggesting an overall increase in terrigenous and volcanic input relative to
biogenic silica. Lithologic boundary may record increased glaciation in the Northern Hemisphere and/or increased volcanic
output. Sedimentation rates are 60-70m/My in the Pleistocene, 100m/My in the younger portion of the upper Pliocene, 3555m/My in the remainder of the Pliocene, and 15m.My in the uppermost Miocene. Major increases in sedimentation rates and
associated flux values (mass accumulation rates of sediment components) occurred at the Pliocene/Miocene boundary and at
the time of the onset of Northern Hemisphere glaciation during the late Pliocene.
Pb isotope ratios of North Pacific sediments, sites 881, 883, and 884; implications for sediment
recycling in the Kamchatkan arc
Kersting, Annie B.
Proceedings of the Ocean Drilling Program, Scientific Results
145 (199511): 383-388
analyzed 13 total samples, 9 from Site 881 (the only Site possibly applicable to the Kurile arc)
abbrev. abstract:
The Pb isotope ratio of 13 sediment samples, collected during ODP Leg 145 at Sites 881, 883, and 884 in the North
Pacific east of the Kamchatkan trench, were determined. The sediments were selected from continuously recovered cores
that are representative of the range of sediment compositions recorded. The sediments analyzed are predominantly pelagic
oozes, representing approx 50Ma of depositional history, and have an age span from Pliocene to Eocene. Pb isotope
covariations of all the samples are more radiogenic than Pacific MORB.
These sediments provide the best analog for previously subducted sediments beneath the Kamchatkan arc.
Previously analyzed basalts from Klychevskoy volcano, Kamchatka, have Pb isotope ratios that fall within the MORB field.
The sediments analyzed in this study are significantly elevated in their Pb isotopic composition to preclude their addition to the
source of the Klychevskoy volcano. Sediment or sediment-derived fluids are not involved in the generation of Klychevskoy
magmas, and are thus not required for arc magmagenesis.
Geochemistry and petrology of volcanic ashes recovered from sites 881 through 884; a
temporal record of Kamchatka and Kurile volcanism
Cao, L. Q.; Arculus, R. J.; McKelvey, Barrie C.
Proceedings of the Ocean Drilling Program, Scientific Results
145 (199511): 345-381
only ashes analyzed
abbrev. abstract:
154 ask layers were sampled during ODP Leg 145 at Sites 881, 883, and 884, in the NW Pacific. The Miocene to
Recent ashes are interpreted to be explosive eruption products of the Kurile-Kamchatka arc system. 5 major pulses are
recoreded in the last 3Ma. High Ba/Nb of Paleogene ashes consistent with IAB rather than MORB or OIB source. 12
compositional groups identified based on REE and Rb, Ba, Th, U, La, Ce, Y, Yb, and Lu.
Pb isotope composition of Klyuchevskoy Volcano, Kamchatka and North Pacific sediments;
implications for magma genesis and crustal recycling in the Kamchatkan arc
Kersting, Annie B.; Arculus, Richard J.
Earth and Planetary Science Letters
136, no. 3-4 (199512): 133-148
abbrev abstract:
Pb isotopic data are used to constrain the chemical contribution of the subducted components in the recycling
beneath the Klyuchevskoy volcano, the most active in the Kamchatken arc. The Pb isotope ratios of the Klyuchevskoy basalts
(206/204=18.26-18.30, 207/204=15.45-15.48, 208/204=37.83-37.91) define a narrow range that falls within the Pacific MORB
field and are among the least radiogenic IAB measured to date. These data are similar to data from 3 other Quat.
Kamchatkan volcanoes. In contrast, North Pacific sediments (primarily siliceous oozes) collected parallel to the Kamchatkan
trench during ODP Leg 145, have Pb isotopes ratios (206/204=18.51-18.78, 207/204=15.56-15.64, 208/204=38.49-38.75) that
are more radiogenic than either the Klyuchevskoy basalts or Pacific MORB.
Even a small amount of sediment in the source would shift the Pb isotope ratios of the erupted basalts from the
MORB field to more radiogenic values. The absence of 10Be and elevated Pb isotope ratios in the Kamchatkan volcanic
lavas, despite the presence of distinctly radiogenic Pb in the North Pacific sediments, makes it unlikely that sediments or
sediment-derived fluids are involved in the source magmas beneath Kamchatka. The Kamchatkan basalts thus represent an
“end-member” where little-no sediment is involved in terms of crustal recycling and arc magma genesis. The major and trace
elements, Pb, Sr, and Nd isotope data of the Kamchatkan basalts are most consistently explained if derived from a fluidfluxed, peridotic mantle wedge source, wherein the fluid composition is dominantly controlled by dehydration of AOB, imparting
a radiogenic 87Sr/86Sr, and MORB-like Pb isotopic signature to the mantle source.
Site 1179:
From the Initial Reports:
Site 1179 is important because it provides samples representative of the northwest Pacific Cretaceous oceanic crust
and its sedimentary cover. Results from this site will augment those from Leg 185, which characterized material being
subducted into the Mariana and Izu-Bonin Trenches (Plank, Ludden, Escutia, et al., 2000- Leg 185), in addition to results from
prior Deep Sea Drilling Project (DSDP) and ODP drilling in the region. From Site 1179 drilling, we hoped to address the
structure, geochemistry, and isotopic characteristics of the upper ocean crust.
Sediments and sedimentary rock recovered from the 377-m sedimentary column at Site 1179 are clayey siliceous
ooze, clay, and chert. We recovered one core from Hole 1179A, six cores from Hole 1179B, 27 cores from Hole 1179C, and
11 cores from Hole 1179D. Recovery averaged 98.8% in the ooze and clay above 283 mbsf, with lowest recoveries (90%) in
the stiff brown clay (246-283 mbsf). Recovery ranged from 2% to 11% in the cherty section below.
Four sedimentary units with a total thickness of 375 m overlie basaltic crust at Site 1179 (Figs. F12, F13). From the
seafloor downward they range in age from the present to an as-yet-undetermined time in the Early Cretaceous. Unit I, at the
top of the section, consists of clay- and radiolarian-bearing diatom ooze (Fig. F14). It extends from the seafloor to a depth of
221.5 m, where it is late Miocene in age. The siliceous oozes of Units I and II have three principal components: diatoms,
radiolarians, and clay, with proportions that vary from core to core. Diatoms predominate in Unit I, radiolarians are common,
and sponge spicules and silicoflagellates contribute to the siliceous nature of the sediment. A range of greenish colors and
intervals of ichnofossils and laminations suggest that the diatom ooze was deposited in a dysoxic bottom environment; neither
anoxic nor fully oxic conditions prevailed for any extended length of time. Sediment accumulated faster in Unit I than in the
other units, a factor that may have contributed to the dysoxic environment. The diatom ooze resembles other Neogene
sections cored in the northwest Pacific (Fig. F5), with its beds of gray silicic vitric ash of a few centimeters thickness,
numerous thin, firm dark green clay layers, and contributions of illitic clay, quartz, and glass within the ooze.
The contact between Units I and II is gradational, both in color and composition, as olive-colored diatomaceous ooze
gives way to yellowish brown radiolarian ooze. The top of Unit II is placed at the base of Chron C4n.1n, below which
radiolarians predominate. This clay-rich diatom-bearing radiolarian ooze is 24.5 m thick. It extends to 246.0 mbsf, where it is
of early late Miocene age. Accumulation was slower than in Unit I. The brown coloration, mottling by burrowing, and a virtual
lack of other sedimentary structures indicate an oxic environment (Fig. F15). The base of Unit II is also a gradational one,
where radiolarian remains vanish downward and the (pelagic) clay of Unit III prevails. In time, this contact represents the
return of the deposition and preservation of siliceous microfossils in the North Pacific during the Miocene.
The pelagic brown clay of Unit III is ~37.5 m thick and extends down to ~283.5 mbsf. Its age is unknown, as it is
barren of fossils except for a few fish teeth and bone fragments, and there is no clear pattern of magnetic reversals except in
the upper ~11 m. The clay is zeolitic, ferruginous, mottled, and compact (Fig. F16). Core recovery was excellent (101.4%) in
all of Units I, II, and III. Unit IV is chert residing in an unknown host formation that was not recovered. It extends from 283.5 to
377.15 mbsf, and its age has yet to be determined. Recovery of this 93.65-m-thick section was poor (6.7%), both as a
percentage of the penetration and in the degree of fracturing. Most pieces are of vitreous chert (Fig. F17), with a wide range of
colors, mottling, healed brecciation, and veins, but a few are pieces of porcellanite. A fauna of poorly preserved radiolarians in
the porcellanite appear to be Early Cretaceous in age and may allow better shore-based determination of age of at least part
of the cherty section.
Cores collected in the northwest Pacific basin by the Deep Sea Drilling Project (DSDP) (Legs 6, 20, 32, and 86) and
ODP (Legs 185 and 191) over the last 30 yr show similar stratigraphy with three primary layers (Fisher, Heezen, et al., 1971;
Heezen, MacGregor, et al., 1973; Larson, Moberly, et al., 1975; Heath, Burckle, et al., 1985; Plank, Ludden, Escutia, et al.,
2000). At the top is a Miocene to Pleistocene blanket of siliceous clay and oozes that contains numerous ash layers. In these
sediments, diatoms and radiolarians are common to abundant but few calcareous microfossils are found. This Neogene layer
can be >200 m thick. Comparison with holes located southeast of Shatsky Rise (Fig. F4) indicates that this layer is largely
absent or attenuated in that region. This observation implies that the thick Neogene layer results from productivity in divergent
waters northeast of the western boundary current. In its lower reaches, the Neogene clayey layer may contain zeolite. The
gray to olive siliceous clays and oozes typically pass downward to barren brown or reddish brown clays. Although the age of
these clays is usually undetermined, at some sites it belongs to the mid- to Late Cretaceous (e.g., Sites 51, 194, and 195) but
it may contain a highly condensed Tertiary section as well (e.g., Site 576). Beneath the barren clays is an often poorly
recovered layer consisting of calcareous oozes, chalk, or marl deposited soon after the formation of the crust while it was at a
depth above the calcite compensation depth (CCD). This layer suffered poor recovery because it is associated with chert and
porcellanite layers that are ubiquitous in the northwest Pacific. During rotary drilling using water as a flushing agent, the chert
causes the formation to be ground up and the softer parts to wash away, generally leaving only rounded chert fragments and
slight traces of the softer matrix. In many holes, the top of the chert layer seems to correspond to the top of the calcareous
section (Fig. F4) but this relationship is difficult to discern in some holes owing to poor recovery. In some other holes, however,
the chert appears higher in the section with the barren brown clays.
ref site
n (analyses)
thickness (m)
density (g/cc)
wt% H2O
mass fraction
SiO2
TiO2
Al2O3
FeO*
MnO
MgO
CaO
Na2O
K2O
P2O5
CO2
H2O+
Sc
V
Cr
Co
Ni
Cu
Zn
Rb
Cs
Sr
Ba
Y
Zr
Hf
Nb
Ta
La
Ce
Nd
Sm
Eu
Gd
Dy
Er
Yb
Lu
Pb
Th
U
87Sr/86Sr
143Nd/144Nd
206Pb/204/Pb
207Pb/204/Pb
208Pb/204/Pb
Kurile Arc
diatom. clay pelagic clay clay + chert
579
581
581
6
3
2
240
30
65
1.49
1.82
2.1
50
35
12.4
0.5348331 0.106159 0.35767412
70.77
49.42
72.64
0.478
0.59
0.09
12.16
14.98
1.23
4.6
6.25
1.88
0.31
2.13
0.07
2.2
3.1
0.44
0.73
0.57
0.55
3.5
1.96
2.5
2.31
2.85
0.44
0.093
0.267
0.345
0
0
0
2.32
17.19
19.62
14.6
31.1
3.3
102
138
42
42
51.7
26
18.7
178.2
5.1
46.7
332.3
17.5
80.8
277
44
89.8
157.3
33.5
77.7
121.7
15
6.57
10.4
1.05
115
163
22
918
988
86
21.2
55.7
32.5
104.8
182
20
2.79
4.33
0.42
9
13.33
4
0.42
0.653
0.07
19.48
46.9
18.2
45.55
201.3
12.05
19.78
48.47
17.55
4.49
13.29
4.71
1
3.04
1.09
3.8
13
4.5
3.7
10
4.2
2.4
6
2.5
2.41
6.19
2.43
0.37
0.95
0.37
29.4
53.3
6.4
7.47
17.5
1
1.872
1.876
0.525
0.71057
0.71271
0.71297
0.51234
0.51234
0.51234
18.894
18.615
18.781
15.701
15.681
15.678
38.892
38.912
38.784
bulk
90sudbuction rate (mm/yr)
1650trench length (km)
335thickness (m)
1.64density (g/cc)
39.15water %
334.3099calc check
69.17
69.078
0.35
0.350
8.55
8.534
3.8
3.796
0.42
0.417
1.67
1.663
0.65
0.648
2.98
2.974
1.7
1.695
0.2
0.201
0
0.000
10.1
10.083
12.29
12.290
84
84.225
37.3
37.251
30.8
30.743
66.6
66.513
88.5
88.358
76.8
76.709
59.9
59.841
5
4.993
87
86.679
627
626.622
28.9
28.876
83
82.525
2.1
2.102
7.67
7.659
0.319
0.319
21.94
21.907
50.11
50.041
22.03
22.002
5.5
5.497
1.24
1.247
5.03
5.022
4.55
4.543
2.82
2.815
2.82
2.815
0.432
0.431
23.68
23.671
6.22
6.211
1.39
1.388
0.71121
0.710708
0.51234
0.511657
18.816
18.79876
15.694
15.66971
38.886
38.80362