11. LATE CENOZOIC ICE-RAFTING RECORDS FROM LEG 145 …L.A. KRISSEK 60°N 50c 40' 150°E 180° 150°...
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Rea, D.K., Basov, I.A., Scholl, D.W., and Allan, J.F. (Eds.), 1995 Proceedings of the Ocean Drilling Program, Scientific Results, Vol. 145 11. LATE CENOZOIC ICE-RAFTING RECORDS FROM LEG 145 SITES IN THE NORTH PACIFIC: LATE MIOCENE ONSET, LATE PLIOCENE INTENSIFICATION, AND PLIOCENE-PLEISTOCENE EVENTS 1 Lawrence A. Krissek 2 ABSTRACT Ice-rafted debris (IRD) in marine sediments provides a valuable direct indicator of the presence of glacial ice at sea level on surrounding continents, and is therefore a useful tool in paleoclimatic studies. The location of sites drilled during Ocean Drilling Program Leg 145, combined with the length, stratigraphic integrity, and good age control of the sediments recovered, provides an opportunity to examine the Late Cenozoic record of North Pacific ice rafting at locations within a few hundred kilometers of potential IRD sources. Ice-rafting records for Sites 881, 883, and 887 have been determined, with temporal resolution ranging from one sample per 10 k.y. to one sample per 50 k.y. The mass accumulation rate (MAR) of IRD in the coarse sand-sized fraction of each sample has been calculated from the abundance of coarse sand (wt%), the IRD abundance within the coarse sand fraction (vol%), shipboard measurements of sediment dry-bulk density, and average sedimentation rates constrained by shipboard paleomagnetic and biostratigraphic data. The oldest occurrences of IRD in Leg 145 cores are at least late Miocene in age, and variations in IRD MARs prior to 2.6 Ma are consistent with interpretations of an older episode of tidewater glaciation (~6 to ~4.2 Ma) and a mid-Pliocene warm interval (-4.2 to -3.0-3.5 Ma) recorded in the Yakataga Formation of coastal Alaska. The age of initial IRD input is younger at Deep Sea Drilling Project (DSDP) sites farther south. IRD MARs at all three sites increase markedly at 2.6 Ma, recording the onset of continental-scale glaciation in the Northern Hemisphere. An accompanying increase in the abundance of volcanic ash may indicate a linkage between volcanism and climate that merits additional study. Pliocene-Pleistocene IRD MARs decrease from the Gulf of Alaska towards the west and from the northwesternmost Pacific towards the east, which identifies the Alaskan coast and the Kurile/Kamchatka margin as major IRD sources. At least eight episodes of increased IRD MARs can be correlated among Leg 145 sites, and most of these can be correlated to IRD records from DSDP Sites 579 and 580. These increases also correlate to North Pacific-wide episodes described previously, indicating that the Leg 145 IRD MAR records contain the major features of North Pacific paleoclimatic history. Pliocene-Pleistocene IRD MAR fluctuations at Sites 881 and 887 exhibit quasi-periodic cyclicity with average durations near orbital values. These results suggest that additional high-resolution studies of sediments from Sites 881 and 887 may yield the first North Pacific IRD records comparable in detail to IRD records from the North Atlantic. INTRODUCTION In marine sedimentary sequences deposited away from a conti- nental margin and at mid to high latitudes, the presence of anoma- lously coarse-grained (sand-sized and larger) terrigenous clasts within a finer grained pelagic or hemipelagic matrix provides a valuable direct indicator of the effect of sediment transport by floating ice. As a result, the stratigraphic distribution of such dropstones (i.e., ice- rafted detritus or IRD) can be used to identify times when continental glaciers extended to sea level, whereas the geographic distribution and the composition of the IRD can be used to locate the glaciated source areas. Sediments recovered during Ocean Drilling Program (ODP) Leg 145 from the North Pacific contain IRD, and potentially carry valuable records of the Late Cenozoic glacial history of the Northern Hemisphere; the examination of those records is the objec- tive of this study. The sediments recovered during Leg 145 are par- ticularly suitable for this work because: (1) essentially complete and undisturbed upper Miocene through Pleistocene sections were recov- ered at each site (Rea, Basov, Janecek, Palmer-Julson, et al., 1993); (2) well-constrained magneto- and biostratigraphies were constructed for each Pliocene-Pleistocene section from shipboard data, and will eventually be supplemented by shore-based paleomagnetic, biostrati- graphic, and isotopic studies; and (3) Leg 145 sites are located in a transect across the North Pacific (Fig. 1), ranging from a site near a 1 Rea, D.K., Basov, LA., Scholl, D.W., and Allan, J.F. (Eds.), 1995. Proc. ODP, Sci. Results, 145: College Station, TX (Ocean Drilling Program). 2 Department of Geological Sciences, The Ohio State University, 130 Orton Hall, So. Oval, Columbus, OH 43210, U.S.A. potential source of IRD in the Kurile-Kamchatka region (Site 881), through an ice-distal location at Detroit Seamount (Site 883), to a site located near potential IRD sources surrounding the Gulf of Alaska (Site 887). Previous studies of IRD in the North Pacific have examined ma- terials recovered during Deep Sea Drilling Project (DSDP) Leg 19 (Stewart et al, 1973; Fullam et al., 1973), during Leg 18 (von Heune et al, 1973,1976), from piston cores (Conolly and Ewing, 1970; Kent et al., 1971), and during DSDP Leg 86 (Krissek et al., 1985). Conolly and Ewing (1970) used coarse-fraction data from 22 Vema piston cores to delineate the horizontal and vertical distribution of IRD in the northwest Pacific Ocean. In these samples, the first IRD is younger than approximately 2.2 Ma, IRD becomes common in sediments younger than 1.5 Ma, and IRD is abundant in sediments younger than 1.0 Ma. Limited magneto- and biostratigraphic data prevented the development of a detailed IRD chronology. Geographic distribution and composition of the IRD were interpreted (Conolly and Ewing, 1970) to indicate IRD source areas in the Kurile-Kamchatka-Aleutian arc, with dispersal by a Pleistocene current system similar to the one now in the area. Kent et al. (1971) used coarse-fraction data and detailed paleomagnetic, biostratigraphic, and tephrochronologic age control from nine piston cores to construct a generalized chronology of relative ice-rafting importance in the North Pacific. This chronol- ogy includes four periods of increased ice-rafting between 1.2 and 2.5 Ma, and at least 11 such intervals from 1.2 Ma to the present. IRD studies of sediments recovered during DSDP Legs 19 (Stewart et al., 1973; Fullam et al., 1973) and 18 (von Heune et al., 1973,1976) were hampered by the discontinuous and limited recovery of the cored sections. As demonstrated by von Heune et al. (1973): (1) the abun- 179
Transcript of 11. LATE CENOZOIC ICE-RAFTING RECORDS FROM LEG 145 …L.A. KRISSEK 60°N 50c 40' 150°E 180° 150°...
Rea, D.K., Basov, I.A., Scholl, D.W., and Allan, J.F. (Eds.), 1995Proceedings of the Ocean Drilling Program, Scientific Results, Vol. 145
11. LATE CENOZOIC ICE-RAFTING RECORDS FROM LEG 145 SITES IN THE NORTH PACIFIC:LATE MIOCENE ONSET, LATE PLIOCENE INTENSIFICATION,
AND PLIOCENE-PLEISTOCENE EVENTS1
Lawrence A. Krissek2
ABSTRACT
Ice-rafted debris (IRD) in marine sediments provides a valuable direct indicator of the presence of glacial ice at sea level onsurrounding continents, and is therefore a useful tool in paleoclimatic studies. The location of sites drilled during Ocean DrillingProgram Leg 145, combined with the length, stratigraphic integrity, and good age control of the sediments recovered, provides anopportunity to examine the Late Cenozoic record of North Pacific ice rafting at locations within a few hundred kilometers ofpotential IRD sources.
Ice-rafting records for Sites 881, 883, and 887 have been determined, with temporal resolution ranging from one sample per10 k.y. to one sample per 50 k.y. The mass accumulation rate (MAR) of IRD in the coarse sand-sized fraction of each sample hasbeen calculated from the abundance of coarse sand (wt%), the IRD abundance within the coarse sand fraction (vol%), shipboardmeasurements of sediment dry-bulk density, and average sedimentation rates constrained by shipboard paleomagnetic andbiostratigraphic data.
The oldest occurrences of IRD in Leg 145 cores are at least late Miocene in age, and variations in IRD MARs prior to 2.6 Maare consistent with interpretations of an older episode of tidewater glaciation (~6 to ~4.2 Ma) and a mid-Pliocene warm interval(-4.2 to -3.0-3.5 Ma) recorded in the Yakataga Formation of coastal Alaska. The age of initial IRD input is younger at Deep SeaDrilling Project (DSDP) sites farther south. IRD MARs at all three sites increase markedly at 2.6 Ma, recording the onset ofcontinental-scale glaciation in the Northern Hemisphere. An accompanying increase in the abundance of volcanic ash may indicatea linkage between volcanism and climate that merits additional study.
Pliocene-Pleistocene IRD MARs decrease from the Gulf of Alaska towards the west and from the northwesternmost Pacifictowards the east, which identifies the Alaskan coast and the Kurile/Kamchatka margin as major IRD sources. At least eight episodesof increased IRD MARs can be correlated among Leg 145 sites, and most of these can be correlated to IRD records from DSDPSites 579 and 580. These increases also correlate to North Pacific-wide episodes described previously, indicating that the Leg 145IRD MAR records contain the major features of North Pacific paleoclimatic history.
Pliocene-Pleistocene IRD MAR fluctuations at Sites 881 and 887 exhibit quasi-periodic cyclicity with average durations nearorbital values. These results suggest that additional high-resolution studies of sediments from Sites 881 and 887 may yield the firstNorth Pacific IRD records comparable in detail to IRD records from the North Atlantic.
INTRODUCTION
In marine sedimentary sequences deposited away from a conti-nental margin and at mid to high latitudes, the presence of anoma-lously coarse-grained (sand-sized and larger) terrigenous clasts withina finer grained pelagic or hemipelagic matrix provides a valuabledirect indicator of the effect of sediment transport by floating ice. Asa result, the stratigraphic distribution of such dropstones (i.e., ice-rafted detritus or IRD) can be used to identify times when continentalglaciers extended to sea level, whereas the geographic distributionand the composition of the IRD can be used to locate the glaciatedsource areas. Sediments recovered during Ocean Drilling Program(ODP) Leg 145 from the North Pacific contain IRD, and potentiallycarry valuable records of the Late Cenozoic glacial history of theNorthern Hemisphere; the examination of those records is the objec-tive of this study. The sediments recovered during Leg 145 are par-ticularly suitable for this work because: (1) essentially complete andundisturbed upper Miocene through Pleistocene sections were recov-ered at each site (Rea, Basov, Janecek, Palmer-Julson, et al., 1993);(2) well-constrained magneto- and biostratigraphies were constructedfor each Pliocene-Pleistocene section from shipboard data, and willeventually be supplemented by shore-based paleomagnetic, biostrati-graphic, and isotopic studies; and (3) Leg 145 sites are located in atransect across the North Pacific (Fig. 1), ranging from a site near a
1 Rea, D.K., Basov, LA., Scholl, D.W., and Allan, J.F. (Eds.), 1995. Proc. ODP, Sci.Results, 145: College Station, TX (Ocean Drilling Program).
2 Department of Geological Sciences, The Ohio State University, 130 Orton Hall, So.Oval, Columbus, OH 43210, U.S.A.
potential source of IRD in the Kurile-Kamchatka region (Site 881),through an ice-distal location at Detroit Seamount (Site 883), to a sitelocated near potential IRD sources surrounding the Gulf of Alaska(Site 887).
Previous studies of IRD in the North Pacific have examined ma-terials recovered during Deep Sea Drilling Project (DSDP) Leg 19(Stewart et al, 1973; Fullam et al., 1973), during Leg 18 (von Heuneet al, 1973,1976), from piston cores (Conolly and Ewing, 1970; Kentet al., 1971), and during DSDP Leg 86 (Krissek et al., 1985). Conollyand Ewing (1970) used coarse-fraction data from 22 Vema pistoncores to delineate the horizontal and vertical distribution of IRD in thenorthwest Pacific Ocean. In these samples, the first IRD is youngerthan approximately 2.2 Ma, IRD becomes common in sedimentsyounger than 1.5 Ma, and IRD is abundant in sediments younger than1.0 Ma. Limited magneto- and biostratigraphic data prevented thedevelopment of a detailed IRD chronology. Geographic distributionand composition of the IRD were interpreted (Conolly and Ewing,1970) to indicate IRD source areas in the Kurile-Kamchatka-Aleutianarc, with dispersal by a Pleistocene current system similar to the onenow in the area. Kent et al. (1971) used coarse-fraction data anddetailed paleomagnetic, biostratigraphic, and tephrochronologic agecontrol from nine piston cores to construct a generalized chronologyof relative ice-rafting importance in the North Pacific. This chronol-ogy includes four periods of increased ice-rafting between 1.2 and 2.5Ma, and at least 11 such intervals from 1.2 Ma to the present.
IRD studies of sediments recovered during DSDP Legs 19 (Stewartet al., 1973; Fullam et al., 1973) and 18 (von Heune et al., 1973,1976)were hampered by the discontinuous and limited recovery of the coredsections. As demonstrated by von Heune et al. (1973): (1) the abun-
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L.A. KRISSEK
60°N
50c
40'
150°E 180° 150° 120°
Figure 1. Location map of ODP Leg 145 sites in the North Pacific Ocean. From Rea, Basov, Janecek, Palmer-Julson, et al. (1993).
dance of the coarse sand fraction (250 µm-2 mm) in the Gulf ofAlaska is an accurate indicator of IRD abundance, and (2) periods ofIRD influx lasted approximately 10,000 to 20,000 years. In subsequentwork, von Heune et al. (1976) used data from Site 178 and a piston coreto construct an IRD chronology for the past 300 k.y. in the Gulf ofAlaska; this chronology correlates positively with variations in otherNorthern Hemisphere climatic indicators during the same period.
At DSDP Sites 579 and 580, located in the northwest Pacific, IRDabundances are generally lower than in the study areas located farthernorth and east (Krissek et al, 1985). Despite this limitation, IRD firstappears at Sites 579 and 580 at approximately 2.6 Ma, the importanceof IRD increases in sediments deposited since approximately 1.0 Ma,and peaks in IRD importance since 1.0 Ma are generally synchronouswith periods of major ice rafting throughout the North Pacific (asdefined by Kent et al., 1971). In contrast to the findings of von Heuneet al. (1973), the coarse-sand fraction at Sites 579 and 580 contains asignificant non-IRD component, so that the abundance of the coarse-sand fraction is not an accurate indicator of IRD abundance. Instead,both the abundance and the composition of the coarse sand fractionmust be known to accurately define the spatial and temporal distri-bution of IRD.
Although the details of these previous studies differ (e.g., continu-ity of core recovery, temporal resolution of sampling, grain size ofsediment designated as IRD), the general conclusions of these studiesare consistent and can be summarized as follows:
1. The abundance of terrigenous coarse-grained material does in-dicate the relative importance of ice rafting at the time of deposition.
2. The IRD has been transported predominantly from majorsource areas on the perimeter of the Gulf of Alaska and along theKurile-Kamchatka margin, so that IRD is most common at locationsin the Gulf of Alaska and the northwestern Pacific. IRD occurrences/abundances decrease from these locations toward the central part ofthe northernmost Pacific, and also decrease to the south at approxi-mately all longitudes.
3. The temporal record of ice rafting includes limited dropstoneoccurrences prior to approximately 2.6 Ma, and significant increasesin IRD abundance at approximately 2.6 Ma (Rea and Schrader, 1985)and 1.0 Ma. This record is interpreted to record the relatively limitedextent of Northern Hemisphere glaciation prior to approximately 2.6Ma, the onset of significant continent-scale Northern Hemisphere gla-
ciation at approximately 2.6 Ma, and the apparent intensification ofNorthern Hemisphere climatic fluctuations since approximately 1.0 Ma.
Recent studies of Miocene and younger strata from the perimeterof the northernmost Pacific have provided additional insight into thelate Miocene and Pliocene climatic history of the region; this record isconsistent with the pre-Pleistocene paleoclimatic history constructedpreviously from marine cores. The oldest IRD found in the YakatagaFormation, which is exposed around the Gulf of Alaska, is dated atapproximately 6 Ma, and sedimentologic and paleontologic data indi-cate significant tidewater glacial effects from approximately 6 Ma toapproximately 4.2 Ma (termed "Glacial A"; Lagoe et al., 1993). Micro-fossil assemblages and reduced IRD abundances in the Yakataga For-mation indicate a relatively warm mid-Pliocene interval from approx-imately 4.2 Ma to sometime between 3.5 and 3.0 Ma (Lagoe et al., 1993);the effects of this mid-Pliocene warm interval have also been recog-nized by Gladenkov et al. (1991) from mollusc, ostracode, and benthicforaminiferal assemblages at Karaginsky Island in eastern Kamchatka.A younger cooling episode ("Glacial B" in the Yakataga Formation;Lagoe et al., 1993) begins between 3.0 and 3.5 Ma in both records, withsubstantial cooling evident at approximately 2.5 to 2.6 Ma.
Sediments recovered during Leg 145 provide a unique opportu-nity to test the proposed Late Cenozoic glacial history of the circum-North Pacific by using IRD records from continuous, undisturbed,and well-dated marine sections. As a result, this study will examineevidence for the onset of ice-rafting in the late Miocene and forpaleoclimatic fluctuations within the Pliocene-Pleistocene. Becauseof shipboard sampling and time constraints, this study is a reconnais-sance examination of the IRD records from three of the Leg 145 sites.Future high-resolution studies, combined with the potential for oxy-gen isotope stratigraphies from Detroit Seamount (Site 883) andPatton-Murray Seamount (Site 887), may provide the first opportu-nity to correlate the North Pacific IRD record directly to isotopicallycalibrated paleoclimatic records from other parts of the world.
MATERIALS AND METHODS
Samples for IRD analysis were taken at regularly spaced intervalsfrom the continuously cored upper Miocene, Pliocene, and Pleisto-cene sections of Sites 881, 883, and 887. The depth ranges sampled,spacing between samples, average sedimentation rates, and resulting
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temporal resolution of sampling are summarized in Table 1. The sedi-mentation rates used to calculate sample ages are average intervalsedimentation rates defined by shipboard paleomagnetic and bio-stratigraphic datums, and have previously been used to estimate massaccumulation rates (MARs) of individual sediment components (Rea,Basov, Janecek, Palmer-Julson, et al., 1993). Shore-based biostrati-graphic and isotopic data may result in significant revisions of theseage-depth models. As indicated in Table 1, the temporal resolution ofthese samples is appropriate for identifying relatively long-term cli-matic trends, but is not appropriate for identifying short-term fluctu-ations (e.g., short orbital periodicities or Atlantic-type "Heinrich"events). Additional high-resolution sampling and improved age con-trol will be required to identify such short-term fluctuations.
Complete descriptions of the lithologic units sampled at each siteare given in Rea, Basov, Janecek, Palmer-Julson, et al. (1993), but themajor characteristics of those units are summarized briefly here. AtSite 881 (Fig. 1), samples were taken from the youngest lithologicunit, Unit I, which consists of 364 m of diatom ooze and clayeydiatom ooze. Lithologic Unit I at Site 881 is subdivided into twosubunits, based on a downcore decrease in terrigenous content and theabsence of volcanic ash in the lower subunit. The boundary betweenthe two subunits at Site 881 (163 m below seafloor [mbsf]) coincideswith the Matuyama/Gauss paleomagnetic boundary (dated at 2.6Ma). The oldest sediments from Site 881 sampled for this study aredated as late Miocene (approximately 7 Ma).
At Site 883 (Fig. 1), samples were taken from lithologic Unit I andthe underlying lithologic Unit IL Lithologic Unit I is composed of 87m of clay with diatoms, diatom ooze, and diatom clay, with abundantvolcanic ash. Lithologic Unit II is composed of 371 m of diatom ooze,with very little volcanic ash. The boundary between Unit I and UnitII lies just below the Matuyama/Gauss paleomagnetic boundary. Theoldest sediments from Site 883 sampled for this study are dated as lateMiocene (approximately 5 Ma).
At Site 887 (Fig. 1), samples were taken from lithologic Unit I andthe underlying lithologic Unit II. Lithologic Unit I is composed of 90m of siliceous silty clay mixed sediments, diatom ooze, and clay, withabundant volcanic ash. Lithologic Unit II is composed of 180 m ofdiatom ooze and a variety of minor lithologies, with less volcanic ashthan is present in Unit I. The boundary between lithologic Units I andII lies just below the Matuyama/Gauss paleomagnetic boundary. Theoldest sediments from Site 887 sampled for this study are dated as lateMiocene (approximately 5.5 Ma).
On the basis of previous studies in the North Pacific (von Heuneet al., 1973, 1976; Krissek et al., 1985), the 250 µm-2 mm grain-sizeinterval was chosen as the indicator of IRD abundance. Samples weredried at 60°C, weighed, disaggregated ultrasonically, and wet-sievedat 2 mm and 250 µm. The 250 µm-2 mm size fraction was then driedand weighed, and the abundance of the coarse-sand fraction (weight%) was calculated. The coarse-sand fraction of each sample wasexamined under a binocular microscope, and the abundance of ter-rigenous, nonvolcanic clasts (volume %) was estimated. The MAR ofcoarse sand-sized IRD was then estimated as
IRD MAR = CS% × IRD% × DBD × LSR,
where IRD MAR is the mass accumulation rate (g/cm2/k.y.), CS% isthe coarse-sand abundance (weight %), IRD% is the IRD abundancein the coarse-sand fraction (volume %), DBD is the dry-bulk densityof the sediment (g/cm3), and LSR is the interval average linearsedimentation rate (cm/k.y.).
All values used in these calculations are given in the Appendix(this chapter). Dry-bulk densities were obtained from the tables ofdiscrete physical properties measurements in the appropriate chaptersof Rea, Basov, Janecek, Palmer-Julson, et al. (1993). The dry-bulkdensity value chosen for each sample is the value of the closest (eitheroverlying or underlying) discrete measurement. Linear sedimentationrates are the average interval values used to calculate component
Table 1. Summary of depth ranges sampled, sample spacing, linear sed-imentation rates,* and resultant temporal sampling interval at Sites881, 883, and 887.
Site
881
883
887
Depth(mbsf)
0-108108-163163-220220-286286-334
0-8686-168
168-3000-56
57-8787-163
Samplespacing
(cm)
150150150
75-15075-150
150150450505050
Sedimentationrate
(cm/k.y.)
5.49.33.45.43.03.39.19.15.42.02.6
Temporalsample spacing
(k.y.)
281644
14-2825-50
4516
102519
Note: *Rea, Basov, Janecek, Palmer-Julson, et al. (1993).
fluxes in the appropriate chapters of Rea, Basov, Janecek, Palmer-Julson, et al. (1993).
In this study, the IRD MAR, rather than the IRD abundance (wt%),is used as an indicator of IRD supply through time. IRD MAR is thepreferred indicator because the MAR of an individual component, suchas IRD, is independent of the supply rates of other components, suchas volcanic ash or biogenic material. It should be noted, however, thatthe IRD MAR calculated in this study may underestimate the actualIRD MAR, because the density of IRD is higher than the densities ofbiogenic material (diatoms, radiolarians, foraminifers) and volcanicash. The IRD MAR calculated for a sample composed only of IRD willbe the actual IRD MAR, but the IRD MAR calculated for a sample con-taining a mixture of IRD and biogenic components will underestimatethe mass contribution from IRD if the volume abundance is not cor-rected for differences in the densities of the components. In this dataset, such underestimates are more important in the deeper (older) partsof the records, where IRD is a minor volumetric constituent (but themajor contributor of mass) in biogenically dominated samples. Coarse-sand abundances are generally very low in the older samples, however,so that increasing the IRD contribution to the coarse-sand abundancestill would not significantly change the overall pattern of IRD MARfluctuations observed at these sites.
DATA
IRD abundances and MARs are tabulated in the Appendix. Theabundance of IRD (weight %) at Sites 881, 883, and 887 is plotted asa function of depth downcore in Figure 2, and IRD MAR profiles foreach site are shown in Figures 3 and 4. IRD abundances at Site 881(Fig. 2A) range between 0 and 6 wt%, with a distinct shift in therecord at 163 mbsf. Above that level, IRD abundances generally fallbetween 0.5 and 3.0 wt%, whereas most abundances below 163 mbsfare very close to zero. The corresponding change on the MAR profiles(Figs. 3A and 4A) occurs at 2.6 Ma, from approximately 0 g/cm2/k.y.to values generally between 0.03 and 0.09 g/cm2/k.y. Maximum IRDMAR values are approximately 0.21 g/cm2/k.y. at Site 881. Most ofthe fluctuations in the IRD MAR record younger than 2.6 Ma includeat least one data point intermediate between the maximum and mini-mum values, suggesting that these fluctuations are not simply an arti-fact of the sampling interval. As a result, these fluctuations may pro-vide a hint of underlying cyclicity within this record.
IRD abundances at Site 883 (Fig. 2B) range between 0 and 0.7wt%, with a distinct shift in the record at 82 mbsf. Above that level,IRD abundances are generally between 0.1 and 0.6 wt%, whereas mostabundances below 82 mbsf are very close to zero. The correspondingchange on the MAR profiles (Figs. 3B and 4B) occurs at approximately2.5 Ma, from approximately 0 g/cm2/k.y. to values generally between0.001 and 0.008 g/cm2/k.y. The magnitude of IRD MAR maxima
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L.A. KRISSEK
A Ice-Rafted Detritus (wt%)
0 1 2 3 4 5 6
B Ice-Rafted Detritus (wt%)
0 0.2 0.4 0.6
Ice-Rafted Detritus (wt%)
0 5 10 15
0
50
JO
ε,£100Q.CDQ
150
350 300 200
Figure 2. Abundance of coarse sand-sized (250 µm-2 mm) IRD as a function of depth (mbsf). Note change in abundance scales between plots. A. Data for Site881. B. Data for Site 883. C. Data for Site 887.
A Mass accumulation rate of
ice-rafted detritus (g/cm2/k.y.)
0 0.1 0.2 0.3
B Mass accumulation rate of
ice-rafted detritus (g/cm2/k.y.)
0 0.008 0.016
C Mass accumulation rate of
ice-rafted detritus (g/cm2/k.y.)
0 0.2 0.4 0.6 0.80
CD
4r
Figure 3. Mass accumulation rate of coarse sand-sized IRD as a function of sediment age for entire record analyzed at each site. Note change in abundance scalesbetween plots. MARs increase at each site at approximately 2.6 Ma. A. Data for Site 881. B. Data for Site 883. C. Data for Site 887.
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A Mass accumulation rate of
ice-rafted detritus (g/cm^/k.y.
0 0.1 0.20
B Mass accumulation rate of
ice-rafted detritus (g/cm2/k.y.
0 0.008 0.016
LATE CENOZOIC ICE-RAFTING RECORDS
C Mass accumulation rate of
ice-rafted detritus (g/cm2/k.y.)
0 0.2 0.4 0.6 0.8
cσ
Figure 4. Mass accumulation rate of coarse sand-sized IRD as a function of sediment age for the interval 0-3 Ma. Note change in abundance scales between plots.Note the quasi-periodic fluctuations between 0 and 2.0 Ma at Site 881, and between 0 and 1.0 Ma at Site 887. A. Data for Site 881. B. Data for Site 883. C. Datafor Site 887.
generally increases from 2.5 to 1.0 Ma, decreases sharply from 1.0 toapproximately 0.7 Ma, and then increases in sediments younger than0.7 Ma. Most peaks in the Site 883 IRD MAR record are defined bysingle points at the corresponding maximum and minima, probablybecause of the relatively long sample spacing in this data set. As aresult, the details of this record (as presently shown in Figs. 3B and4B) are probably more an artifact of the sample spacing than anindicator of actual short-term variations in the IRD MAR.
IRD abundances at Site 887 (Fig. 2C) range between 0 and 15wt%, with a distinct shift in the record at approximately 88 mbsf.Above that level, IRD abundances range between 0 and 15 wt%,whereas most abundances below 88 mbsf are very close to zero. Thecorresponding change on the MAR profiles (Figs. 3C and 4C) occursat 2.6 Ma, from approximately 0 g/cm2/k.y. to values generally be-tween 0.0 and 0.20 g/cm2/k.y. Maximum IRD MAR values at Site 887are approximately 0.40 g/cm2/k.y. Many of the MAR peaks youngerthan 2.6 Ma, and especially those younger than 1.0 Ma, are definedby the two minima, the maximum, and several intermediate values,suggesting that these fluctuations are not an artifact of the samplinginterval. Instead, these fluctuations suggest that short-term cyclicityis a real attribute of the IRD MAR record at Site 887, making this sitean obvious candidate for future high-resolution studies.
DISCUSSION
The data presented in Figures 2,3, and 4, as well as observations ofpebble- to cobble-sized dropstones in the shipboard core descriptions(Rea, Basov, Janecek, Palmer-Julson, et al., 1993), indicate that IRDranges from present to abundant in the upper Miocene through Pleis-tocene sections cored during Leg 145. The records of ice-rafting inves-tigated here provide strong evidence of a major increase in the effectsof glaciation at 2.6 Ma, consistent with the results of previous IRDstudies in the North Pacific and with a variety of paleoclimatic signals
from elsewhere in the Northern Hemisphere. These relatively long andcontinuous records also provide valuable information about both theearly history of late Cenozoic glaciation in the circum-North Pacificand the general patterns of glaciation since approximately 2.6 Ma. Inaddition, these records provide preliminary suggestions of short-termglacial fluctuations since 2.6 Ma; this aspect of the IRD MAR recordshould be examined by high-resolution studies in the future.
Ice-rafting and Glaciation prior to 2.6 Ma
Intervals of ice-rafting prior to 2.6 Ma can be identified by thepresence of peaks in the MAR of coarse sand-sized IRD, as well asby the occurrences of macroscopic IRD recorded in the shipboarddescriptions of the cores. At Site 881, this "older" coarse sand-sizedIRD was deposited at 6.6, 5.5, 4.8-4.9, 4.5-4.6, 4.2, 3.9, 3.8, and3.4-3.7 Ma, and macroscopic IRD was observed in sediments depos-ited at approximately 4.6 and 4.2 Ma. The occurrences younger than4.2 Ma are relatively minor, however, with each based on the presenceof a single terrigenous grain in a single sample. As a result, the recordfrom Site 881 is consistent with previous observations of early glacialeffects from 6 Ma to approximately 4.2 Ma, followed by a mid-Pliocene warm interval with reduced glacial effects from approxi-mately 4.2 Ma to approximately 3.0-3.5 Ma (Gladenkov et al., 1991;Lagoe et al., 1993).
At Site 883, the only occurrence of "older" coarse sand-sized IRDwas deposited at approximately 3.17 Ma, and the only potentialmacroscopic dropstones occur in sediments deposited at approxi-mately 3.0 Ma. In Hole 883B, a lonestone of this age is described as"pumice" (Rea, Basov, Janecek, Palmer-Julson, et al., 1993), whereasthe lithology of a lonestone of the same age in Hole 883C is notdescribed. As a result, it is unclear whether these macroscopic clastsare ice rafted or not. Despite this uncertainty, however, it is clear thatSite 883 received little IRD at any time prior to 2.6 Ma.
183
L.A. KRISSEK
At Site 887, "older" coarse sand-sized IRD was deposited at5.3-5.4, 5.2,4.9, 4.3-4.4, 3.7-3.9, 3.5-3.6, 3.3-3.4, and 3.1 Ma, andmacroscopic IRD was observed in sediments deposited at approxi-mately 4.5 and 3.9 Ma. This distribution of IRD spans both the olderglacial episode and the mid-Pliocene warm interval identified in theYakataga Formation by Lagoe et al. (1993). The IRD distribution atSite 887 may extend into the younger glacial episode of the YakatagaFormation, depending on the actual time of transition from the mid-Pliocene warm interval to the younger glacial (estimated at 3.0-3.5Ma by Lagoe et al., 1993). The presence of IRD in sediments olderthan approximately 4.2 Ma is consistent with the presence of tide-water glaciers that deposited the older glacial interval in the YakatagaFormation. The presence of IRD in sediments deposited at Site 887during the mid-Pliocene warm interval is not inconsistent with obser-vations from the Yakataga Formation, because IRD is observed in themid-Pliocene warm interval of that unit, although in lower abun-dances than in the glacial intervals (Lagoe et al., 1993).
The IRD MAR data presented here, together with the observationsof macroscopic IRD, indicate that ice-rafting began by 5.5-6.0 Ma inboth the Alaskan and Kurile/Kamchatka IRD sources. The first ap-pearance of IRD at a particular site in the North Pacific also dependson the geographic location of that site, however, because the age offirst IRD appearance generally decreases toward the south. In particu-lar, Krissek et al. (1985) identified the oldest IRD at DSDP Sites 579and 580 (approximately 500 km south of Site 881) as late Pliocene inage, and a single pebble of quartz schist, possibly ice-rafted, is re-corded in upper Pliocene sediments at DSDP Site 177 (approximately400 km south of Site 887; Kulm, von Heune, et al., 1973).
Onset of Significant Glaciation and Ice-rafting
In each of the three IRD MAR records analyzed here, as well as inthe general distribution of macroscopic IRD in Leg 145 cores, the im-portance of ice-rafted material increases dramatically at, or very closeto, the Matuyama/Gauss paleomagnetic boundary (2.6 Ma on the timescale of Cande and Kent, 1992). A similar age for the first appearanceof significant IRD was previously reported for the North Pacific(Kent et al, 1971; Krissek, et al., 1985; Rea and Schrader, 1985), theNorth Atlantic (Shackleton et al., 1984; Ruddiman, Mclntyre, andRaymo, 1987; Raymo et al., 1987), and the Norwegian Sea (Krissek,1989; Jansen et al, 1990; Jansen and Sj0holm, 1991). This increasehas generally been interpreted as recording the onset of continental-scale glaciation in the Northern Hemisphere. Limited amounts of IRDfound in sediments older than 2.6 Ma around the perimeter of theNorth Pacific (this study and Lagoe et al., 1993), in the Irminger Basinoff southeastern Greenland (Larsen et al., 1994), and in the Norwe-gian Sea (Krissek, 1989; Jansen et al., 1990; Jansen and Sj0holm,1991) indicate initial glaciation prior to 2.6 Ma, but a variety of datatypes from throughout the Northern Hemisphere indicate a majorchange in Northern Hemisphere paleoclimates at approximately 2.6Ma (e.g., Raymo et al., 1989).
Although this glacial intensification at approximately 2.6 Ma inthe Northern Hemisphere is widely recognized, causes for this changeremain speculative. One set of explanations has focused on the possi-ble modification of Northern Hemisphere atmospheric circulation bylate Neogene uplift in southeastern Asia and southwestern NorthAmerica (Ruddiman, Raymo, and Mclntyre, 1986; Ruddiman andRaymo, 1988). Another set of explanations has proposed linkagesbetween increased rates of uplift in the late Neogene, increased ratesof chemical weathering, and decreased levels of atmospheric andoceanic CO2 (Raymo et al, 1988; Hodell et al, 1989; Raymo andRuddiman, 1992). An older proposal (Kennett and Thunell, 1975)suggested a relationship between increased volcanic activity (as re-corded by increased amounts of volcanic ash in marine cores) at thistime and climatic deterioration, although the details of this relation-ship were not discussed. Although data from Leg 145 can add only asmall piece to this puzzle, these cores do show essentially synchro-
nous increases in the abundance of volcanic ash (used to define theyoungest lithologic units at Sites 881,883, and 887) and in IRD MARat approximately 2.6 Ma. This association suggests that linkagesbetween volcanism and the glacial record should be reconsidered,especially since both records may be related to tectonic activity in thearea. High-resolution studies of Sites 881 and/or 887 are planned tofurther examine these potential linkages.
Spatial Patterns of Pliocene-Pleistocene Ice-rafting
In sediments younger than 2.6 Ma, the IRD MAR maxima arelargest at Site 887 (averaging approximately 0.20 g/cm2/k.y.), inter-mediate at Site 881 (averaging approximately 0.07 g/cm2/k.y.), andsmallest at Site 883 (averaging approximately 0.006 g/cm2/k.y.). Thisspatial pattern indicates that major ice sources were located on theperimeter of the Gulf of Alaska and along the Kurile/Kamchatkamargin, as interpreted previously by Conolly and Ewing (1970).Provenance studies of the Leg 145 IRD are discussed elsewhere(McKelvey, this volume), but the low IRD MARs at Site 883 indicateeither that few icebergs were transported from these sources to thevicinity of Site 883 (Detroit Seamount), or that icebergs passingthrough the area experienced little melting because of cool surfacewaters within an expanded Subarctic Gyre. Direct evidence to distin-guish between these two possibilities will require microfossil-basedreconstructions of sea-surface temperatures at these sites.
Temporal Patterns of Pliocene-Pleistocene Ice-rafting
At least eight episodes of increased IRD MARs can be correlatedamong two or more Leg 145 sites (Fig. 5); this degree of agreementis surprisingly good, considering both the differences in the samplingintervals at Sites 881, 883, and 887, and the uncertainties introducedby using average interval sedimentation rates to calculate sampleages. Most of these eight episodes can be correlated farther south andwest to peaks in the IRD abundance records from DSDP Sites 579and/or 580 (Krissek et al., 1985). The times of increased ice rafting atapproximately 1.09-1.13, 0.92-0.93, 0.76-0.79, 0.68-0.69, 0.55-0.56, 0.31-0.32, 0.27-0.29, and 0.02-0.05 Ma correlate well withNorth Pacific-wide periods of increased ice rafting previously identi-fied by Kent et al. (1971) and by von Heune et al. (1976). Two periodsof a relatively lower amplitude increase, which were identified byKent et al. (1971), are not seen in the Leg 145 data. Despite theabsence of these two smaller IRD peaks, the strong general correla-tion between the Leg 145 data sets and the detailed data of Kent et al.(1971) indicates that the major features of North Pacific paleoclimatichistory are represented in the Leg 145 records.
The relatively low temporal resolution of the Leg 145 IRD MARrecords and the uncertainties in the present age-depth models for thesesites preclude a detailed analysis of short-term (e.g., orbital-scale)cyclicity at this time. The Pliocene-Pleistocene IRD MAR recordsfrom Sites 881 and 887, however, do exhibit quasi-periodic fluctua-tions with average durations near orbital values (i.e., the 19 k.y. and 23k.y precessional cycles, the 41 k.y. obliquity cycle, and the 100 k.y.eccentricity cycle). For example, between nine and 11 maxima arepresent in the Site 881 record between 0.0 and 1.0 Ma, and 11 maximaare present between 1.0 and 2.0 Ma; as a result, the average timebetween maxima is approximately 100 k.y. As another example, be-tween 10 and 12 maxima are present in the Site 887 record between 0.0and 0.5 Ma, and 10 or 11 maxima are present between 0.5 and 1.0 Ma;as a result, the average time between maxima is approximately 40 to50 k.y. The presence of such quasi-cyclic fluctuations in these rela-tively low-resolution records suggests that valuable high-resolutionpaleoclimatic records, perhaps containing evidence of orbital-scalecyclicity, can be developed by future detailed studies of IRD MARs atSites 881 and 887. Such high-resolution IRD records would be the firstfrom the North Pacific comparable in detail to those available fromthe North Atlantic (Shackleton et al., 1984), and would contribute
184
LATE CENOZOIC ICE-RAFTING RECORDS
0 - r
0.2 -
0 .4- -
° • 6 +
0.8- -
1.0--
Site579
Site5 8 0
Site881
Site883
Site887
j — .
i
Figure 5. Correlation diagram of times of increased IRD MARs at ODP Sites881, 883, and 887, and of increased IRD abundance at DSDP Sites 579 and580 (Krissek et al., 1985). Horizontal dashed lines correlate IRD increasesamong sites, and correlate with North Pacific-wide episodes of increased icerafting identified previously by Kent et al. (1971).
significantly to inter-ocean comparisons of behavior during glacial/interglacial fluctuations.
CONCLUSIONS
1. The oldest occurrences of macroscopic IRD and coarse sand-sized IRD in the Leg 145 cores are at least late Miocene in age. IRDoccurrences dated between 6.6 and 4.2 Ma in both the northwestPacific (Site 881) and the Gulf of Alaska (Site 887) correlate withevidence of early tidewater glaciation in the Yakataga Formation ofcoastal Alaska (Lagoe et al., 1993). IRD supply was reduced duringa mid-Pliocene warm interval, which was identified previously fromthe Yakataga Formation (Lagoe et al., 1993) and outcrops in Kam-chatka (Gladenkov et al., 1991). The oldest IRD is younger at loca-tions farther south, with the oldest IRD at DSDP Sites 177, 579, and580 dated as late Pliocene.
2. The MAR of coarse sand-sized IRD increases markedly at, orclose to, the Matuyama/Gauss magnetic boundary (2.6 Ma) at Sites881, 883, and 887, and records the onset of continental-scale glacia-tion in the Northern Hemisphere. The abundance of volcanic ash inthese cores increases synchronously with the IRD MAR change,suggesting that linkages between volcanism and climate proposed byKennett and Thunell (1975) should be reconsidered by future high-resolution studies.
3. During the Pliocene-Pleistocene, the major sources of IRDwere located around the perimeter of the Gulf of Alaska and along theKurile/Kamchatka margin; these results agree with the findings ofConolly and Ewing (1970). Because of the location of these sources,IRD MARs are high in the Gulf of Alaska (Site 887) and the northwestPacific (Site 881), and decrease both toward the center of the north-ernmost Pacific (Site 883) and toward the south. Microfossil-basedreconstructions of sea-surface temperatures will be required to evalu-ate the roles of iceberg trajectories and preferential melting on thedistribution of IRD away from these sources.
4. Within the Pliocene-Pleistocene section, at least eight episodesof increased IRD MARs can be correlated among Leg 145 sites. Mostof these episodes also can be recognized at DSDP Sites 579 and 580,and correlate to basin-wide increases described previously by Kent etal.(1971).Asa result, the Leg 145 IRD MAR records appear to recordthe major features of North Pacific paleoclimatic history.
5. At Sites 881 and 887, Pliocene-Pleistocene fluctuations in IRDMARs exhibit quasi-periodic cyclicity with average durations nearorbital values (-100 k.y. and -40 k.y., respectively). These prelimi-nary results suggest that high-resolution studies at these sites mayyield the first North Pacific IRD records comparable in detail to IRDrecords from the North Atlantic.
ACKNOWLEDGMENTS
This work was supported by a post-cruise JOI-USSSP grant.Thanks to Captain Ed Oonk, the SEDCO drilling crew, Ron Grout,and the ODP technical staff for their assistance during Leg 145. T.Gray and K. Kudless provided able assistance in laboratory analysisof these samples. M. Lagoe and C. Eyles provided helpful reviews ofthis manuscript.
REFERENCES*
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Fullam, T.J., Supko, PR., Boyce, R.E., and Stewart, R.W., 1973. Some aspectsof Late Cenozoic sedimentation in the Bering Sea and North Pacific Ocean.In Creager, J.S., Scholl, D.W., et al., Init. Repts. DSDP, 19: Washington(U.S. Govt. Printing Office), 887-896.
Gladenkov, Y.B., Barinov, K.B., Basilian, A.E., and Cronin, T.M., 1991.Stratigraphy and paleoceanography of Pliocene deposits of KaraginskyIsland, eastern Kamchatka, USSR. Quat. Sci. Rev., 10:239-246.
Hodell, D.A., Mueller, P.A., McKenzie, J.A., and Mead, G.A., 1989. Strontiumisotope stratigraphy and geochemistry of the late Neogene ocean. EarthPlanet. Sci. Lett., 92:165-178.
Jansen, E., and Sj0holm, J., 1991. Reconstruction of glaciation over the past6 Myr from ice-borne deposits in the Norwegian Sea. Nature, 349:600-603.
Jansen, E., Sj0holm, J., Bleil, U., and Erichsen, J.A., 1990. Neogene andPleistocene glaciations in the Northern Hemisphere and late Miocene-Pliocene global ice volume fluctuations: evidence from the NorwegianSea. In Bleil, U., and Thiede, J. (Eds.), Geological History of the PolarOceans: Arctic Versus Antarctic: Dordrecht (Kluwer), 677-705.
Kennett, J.P., and Thunell, R.C., 1975. Global increase in Quaternary explosivevolcanism. Science, 187:497-503.
Kent, D.V., Opdyke, N.D., and Ewing, M., 1971. Climate change in the NorthPacific using ice-rafted detritus as a climatic indicator. Geol. Soc. Am.Bull, 82:2741-2754.
Krissek, L.A., 1989. Late Cenozoic records of ice-rafting at ODP Sites 642,643, and 644, Norwegian Sea: onset, chronology, and characteristics ofglacial/interglacial fluctuations. In Eldholm, O., Thiede, J., Taylor, E., etal., Proc. ODP, Sci. Results, 104: College Station, TX (Ocean DrillingProgram), 61-74.
Krissek, L.A., Morley, J.J., and Lofland, D.K., 1985. The occurrence, abun-dance, and composition of ice-rafted debris in sediments from Deep SeaDrilling Project Sites 579 and 580, northwest Pacific. In Heath, G.R.,Burckle, L.H., et al., Init. Repts. DSDP, 86: Washington (U.S. Govt.Printing Office), 647-655.
Kulm, L.D., von Huene, R., et al, 1973. Init. Repts. DSDP, 18: Washington(U.S. Govt. Printing Office).
Lagoe, M.B., Eyles, CH., Eyles, N., and Hale, C, 1993. Timing of lateCenozoic tidewater glaciation in the far North Pacific. Geol. Soc. Am. Bull,105:1542-1560.
Larsen, H.C., Saunders, A.D., Clift, P.D., Beget, J., Wei, W, Spezzaferri, S.,and ODP Leg 152 Scientific Party, 1994. Seven million years of glaciationin Greenland. Science, 264:952-955.
Raymo, M.E., and Ruddiman, W.F., 1992. Tectonic forcing of late Cenozoicclimate. Nature, 359:117-122.
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Raymo, M.E., Ruddiman, W.F., Backman, J., Clement, B.M., and Martinson,D.G., 1989. Late Pliocene variation in Northern Hemisphere ice sheets andNorth Atlantic deep water circulation. Paleoceanography, 4:413^46.
Raymo, M.E., Ruddiman, W.F., and Clement, B.M., 1987. Pliocene-Pleisto-cene paleoceanography of the North Atlantic at DSDP Site 609. In Ruddi-man, W.F., Kidd, R.B., Thomas, E., et al., Init. Repts. DSDP, 94 (Pt. 2):Washington (U.S. Govt. Printing Office), 895-901.
Raymo, M.E., Ruddiman, W.F., and Froelich, P.N., 1988. Influence of lateCenozoic mountain building on ocean geochemical cycles. Geology,16:649-653.
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Ruddiman, W.F., Mclntyre, A., and Raymo, M., 1987. Paleo-environmentalresults from North Atlantic Sites 607 and 609. In Ruddiman, W.F., Kidd,R.B., Thomas, E., et al., Init. Repts. DSDP, 94 (Pt. 2): Washington (U.S.Govt. Printing Office), 855-878.
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Ruddiman, WE, and Raymo, M.E., 1988. Northern Hemisphere climateregimes during the past 3 Ma: possible tectonic connections. In Shackleton,NJ., West, R.G., and Bowen, D.Q. (Eds.), The Past Three Million Years:
Evolution of Climatic Variability in the North Atlantic Region: Cambridge(Cambridge Univ. Press), 1-20.
Shackleton, NJ., Backman, J., Zimmerman, H., Kent, D.V., Hall, M.A.,Roberts, D.G., Schnitker, D., Baldauf, J.G., Desprairies, A., Homrig-hausen, R., Huddlestun, P., Keene, J.B., Kaltenback, A.J., Krumsiek,K.A.O., Morton, A.C., Murray, J.W, and Westberg-Smith, J., 1984. Oxy-gen isotope calibration of the onset of ice-rafting and history of glaciationin the North Atlantic region. Nature, 307:620-623.
Stewart, R.J., Natland, J.H., and Glassley, W.R., 1973. Petrology of volcanicrocks recovered on DSDP Leg 19 from the North Pacific Ocean and theBering Sea. In Creager, J.S., Scholl, D.W, et al., Init. Repts. DSDP, 19:Washington (U.S. Govt. Printing Office), 615-627.
von Huene, R., Crouch, J., and Larson, E., 1976. Glacial advance in the Gulfof Alaska area implied by ice-rafted material. In Cline, R.M., and Hays,J.D. (Eds.), Investigation of Late Quaternary Paleoceanography andPaleoclimatology. Mem.—Geol. Soc. Am., 145:411-422.
von Huene, R., Larson, E., and Crouch, J., 1973. Preliminary study of ice-rafted erratics as indicators of glacial advances in the Gulf of Alaska. InKulm, L.D., von Huene, R., et al., Init. Repts. DSDP, 18: Washington (U.S.Govt. Printing Office), 835-842.
Date of initial receipt: 4 April 1994Date of acceptance: 19 September 1994Ms 145SR-118
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APPENDIX
Data Used to Calculate Mass Accumulation Rates of Coarse-sand Ice-rafted Detritus at Sites 881, 883, and 887
Core, section,interval (cm)
145-881B-1H-1, 103-1081H-2, 103-1081H-3, 98-1032H-1,95-1002H-2, 101-1062H-3, 102-1072H-4, 105-1102H-5, 100-1052H-6, 101-1063H-1, 102-1073H-2, 102-1073H-3, 101-1063H-4, 101-1063H-5, 98-1033H-6, 95-1004H-1, 103-1084H-2, 103-1084H-3, 103-1084H-4, 103-1084H-5, 103-1084H-6, 103-1085H-1, 104-1095H-2, 104-1095H-3, 114-1195H-4, 104-1095H-5, 104-1095H-6, 100-1056H-1, 103-1086H-2, 120-1256H-3, 105-1106H-4, 103-1086H-5, 103-1086H-6, 92-977H-1, 103-1087H-2, 103-1087H-3, 103-1087H-4, 103-1087H-5, 103-1087H-6, 103-1088H-1, 103-1088H-2, 102-1078H-3, 102-1078H-4, 103-1088H-5, 104-1098H-6, 103-1089H-1, 103-1089H-2, 103-1089H-3, 103-1089H-4, 103-1089H-5, 103-1089H-6, 103-10810H-1, 110-11510H-2, 97-10210H-3, 114-11910H-4, 108-11310H-5, 109-11410H-6, 107-10910H-6, 112-11411H-1, 98-10311H-2, 103-10811H-3, 106-11111H-4, 104-10911H-5, 109-11411H-6, 105-11012H-1, 103-10812H-2, 103-10812H-3, 103-10812H-4, 103-10812H-5, 103-10812H-6, 103-10813H-1, 113-11813H-2, 100-10513H-3, 107-11213H-4, 111-11613H-5, 102-10714H-1, 107-11214H-2, 103-10814H-3, 102-10714H-4, 102-10714H-5, 101-10615H-1, 108-11315H-2, 104-10815H-3, 109-11215H-4, 104-108
Depth(mbsf)
1.032.533.986.458.019.52
11.0512.514.0116.0217.5219.0120.5121.9823.4525.5327.0328.5330.0331.5333.0335.0436.5438.1439.5441.0442.544.5346.247.5549.0350.5351.9254.0355.5357.0358.5360.0361.5363.5365.0266.5268.0369.5471.0373.0374.5376.0377.5379.0380.5382.683.9785.6487.0888.5990.0790.1291.9893.5395.0696.5498.0999.55
101.53103.03104.53106.03107.53109.03111.13112.5114.07115.61117.02120.57122.03123.52125.02126.51130.08131.54133.09134.54
Age(Ma,
calculated)
0.0190.0470.0740.1190.1480.1760.2050.2310.2590.2970.3240.3520.3800.4070.4340.4730.5010.5280.5560.5840.6120.6490.6770.7060.7320.7600.7870.8250.8560.8810.9080.9360.9611.0011.0281.0561.0841.1121.1391.1761.2041.2321.2601.2881.3151.3521.3801.4081.4361.4641.4911.5301.5551.5861.6131.6411.6681.6691.7031.7321.7601.7881.8161.8441.8801.9081.9361.9641.9912.0112.0342.0482.0652.0822.0972.1352.1512.1672.1832.1992.2372.2532.2702.285
CSD(wt%)
0.792.590.700.000.000.570.002.023.352.132.290.391.641.830.171.221.180.808.412.991.501.322.311.112.214.173.181.201.961.431.652.813.403.072.472.972.343.620.060.008.811.830.651.906.538.094.361.961.212.122.921.411.691.531.511.690.770.191.781.722.342.432.393.293.623.221.410.960.361.640.720.763.892.751.481.812.450.090.447.24
17.620.541.530.79
IRD(vol%)
100.00100.00
0.000.000.00
75.000.00
80.00100.00100.0099.0035.0040.0070.0025.0070.0090.0025.0060.0070.0085.0055.0065.0075.0065.0065.0070.0050.0065.0090.0060.0060.0080.0080.0080.0060.0050.0070.00
100.000.00
40.0070.0050.0040.0085.0025.0090.0075.0040.0060.0080.0050.0065.0065.0060.0085.0040.0020.0090.0070.0050.0070.0085.0020.0070.0050.0085.0080.0070.0065.0060.0050.0030.0090.0050.0060.0070.0010.0040.0010.005.00
80.0080.0050.00
IRD(wt%)
0.792.590.000.000.000.430.001.623.352.132.260.140.661.280.040.861.060.205.052.091.280.731.500.831.442.712.230.601.271.290.991.682.722.461.981.781.172.530.060.003.521.280.330.765.552.023.931.470.481.272.340.711.100.990.901.440.310.041.601.201.171.702.030.662.541.611.200.760.251.060.430.381.172.470.741.091.710.010.180.720.880.431.230.39
LSR(cm/k.y.)
5.45.45.45.45.45.45.45.45.45.45.45.45.45.45.45.45.45.45.45.45.45.45.45.45.45.45.45.45.45.45.45.45.45.45.45.45.45.45.45.45.45.45.45.45.45.45.45.45.45.45.45.45.45.45.45.45.45.45.45.45.45.45.45.45.45.45.45.45.49.39.39.39.39.39.39.39.39.39.39.39.39.39.39.3
DBD(g/cm3)
0.640.590.640.560.590.510.720.620.60.680.710.490.640.680.390.690.490.710.780.770.670.750.610.810.650.70.730.710.660.780.760.690.670.610.680.550.780.730.720.471.060.870.50.870.720.750.680.790.530.90.740.760.710.730.680.630.550.550.660.870.60.640.650.710.630.70.740.560.630.730.60.730.60.740.790.770.710.620.580.70.820.550.590.74
IRD MAR(g/cm2/k.y.)
0.0270.0830.0000.0000.0000.0120.0000.0540.1090.0780.0870.0040.0230.0470.0010.0320.0280.0080.2130.0870.0460.0290.0500.0360.0510.1020.0880.0230.0450.0540.0410.0630.0980.0810.0730.0530.0490.1000.0030.0000.2020.0600.0090.0360.2160.0820.1440.0630.0140.0620.0930.0290.0420.0390.0330.0490.0090.0010.0570.0570.0380.0590.0710.0250.0860.0610.0480.0230.0090.0720.0240.0260.0650.1700.0540.0780.1130.0010.0100.0470.0670.0220.0670.027
187
L.A. KRISSEK
APPENDIX (continued).
Core, section,interval (cm)
15H-5, 105-10915H-6, 105-10916H-1, 104-10916H-2, 104-10916H-3, 109-11416H-4, 104-10916H-5, 104-10916H-6, 97-10217H-1, 103-10817H-2, 103-10817H-3, 132-13717H-4, 103-10817H-5, 114-11917H-6, 131-13618H-1, 103-10818H-2, 103-10818H-3, 103-10818H-4, 103-10818H-5, 98-10318H-6, 103-108
145-881C-18X-1,46^818X-1,70-7518X-2, 44-4618X-2, 64-6918X-3, 31-3618X-3, 43-4521H-1, 39-4121H-1 ,69 -7421H-2,69-7421H-3, 12-1421H-3, 69-7421H-4, 69-7421H-5, 12-1421H-5,69-7421H-6, 74 -792 3 X - 1 , 6 8 - 7 323X-2, 69-7423X-3, 89-9423X-4, 70 -7523X-5, 70 -7523X-6, 70 -7523X-7, 15-2025X-1, 12-142 5 X - 1 , 8 0 - 8 525X-2, 78 -8325X-3, 12-1425X-3, 80-8525X-4, 23-2825X-5, 12-1427X-1, 12-142 7 X - 1 , 8 3 - 8 827X-2, 83-8827X-3. 12-1427X-3. 83-8827X-4, 83-8827X-5, 12-1427X-5, 83-8827X-6, 53-5829X-1, 11-1329X-1, 84-8929X-2, 84-8929X-3, 13-1429X-3, 84-8930X-1, 14-1630X-1, 83-8830X-2, 83-8830X-3, 12-1430X-3, 84-8930X-4, 83-8830X-5, 12-1430X-5, 84-8930X-6, 12-1430X-6, 84-8932X-1, 12-143 2 X - 1 , 8 4 - 8 932X-2, 89-9432X-3, 12-1435X1,9-1135X-1, 84-8935X-2, 84-8935X-3, 12-1435X-3, 89-9435X-4, 84-8935X-5, 11-1335X-5, 84-893 6 X - 1 , 2 1 - 2 3
Depth(mbsf)
136.05137.55139.54141.04142.59144.04145.54146.97149.03150.53152.32153.53155.14156.81158.53160.03161.53163.03164.48166.03
156.26156.5157.74157.94159.11159.23182.09182.39183.89184.82185.39186.89187.82188.39189.94201.28202.79204.49205.8207.3208.8209.25219.12219.8221.28222.12222.8223.73224.14238.42239.13240.63241.42242.13243.63244.42245.13246.33257.71258.44259.94260.62261.34267.34268.03269.53270.32271.04272.53273.32274.04274.82275.54286.62287.34288.89289.62315.49316.24317.74318.52319.29320.74321.51322.24325.31
Age
(Ma,calculated)
2.3022.3182.3392.3552.3722.3882.4042.4192.4412.4572.4772.4902.5072.5252.5432.5592.5762.5922.6142.660
2.3722.3792.4162.4222.4562.4603.1323.1413.1853.2123.2293.2733.3013.3173.3633.6963.7413.7913.8293.8743.9183.9314.1504.1634.1904.2064.2194.2364.2434.5084.5214.5494.5634.5764.6044.6194.6324.6544.8654.8794.9064.9194.9325.0435.0565.0845.0995.1125.1395.1545.1675.1825.1955.4005.4115.4635.4876.3506.3756.4256.4516.4766.5256.5506.5756.677
CSD(wt%)
1.945.485.850.591.862.681.131.491.891.372.171.751.921.270.300.710.842.020.220.20
0.390.850.660.611.941.480.520.540.420.440.340.950.371.030.880.580.000.070.230.240.120.560.390.300.484.920.120.230.126.500.130.170.110.140.210.240.000.250.450.270.490.231.620.390.340.310.290.330.190.240.210.150.220.230.230.025.000.190.180.101.190.250.110.040.100.23
IRD(vol%)
50.0065.0060.0050.0020.0080.0050.0020.0080.0095.0020.0065.0080.0060.0020.0080.0070.0050.00
0.0020.00
30.0060.0020.0010.0020.0025.00
0.000.000.000.000.000.000.000.005.00
10.000.000.00
10.000.000.005.000.000.005.000.005.000.002.00
90.000.000.00
30.000.000.00
10.000.000.00
40.000.000.00
20.000.000.000.000.000.000.005.000.000.00O.Oü0.00
10.000.00
50.0080.00
0.000.000.000.001.00
10.000.00
30.000.00
IRD(wt%)
0.973.563.510.300.372.150.570.301.511.300.431.141.540.760.060.570.591.010.000.04
0.120.510.130.060.390.370.000.000.000.000.000.000.000.000.040.060.000.000.020.000.000.030.000.000.020.000.010.000.005.850.000.000.030.000.000.020.000.000.180.000.000.050.000.000.000.000.000.000.010.000.000.000.000.020.000.014.000.000.000.000.000.000.010.000.030.00
LSR(cm/k.y.)
9.39.39.39.39.39.39.39.39.39.39.39.39.39.39.39.39.39.33.43.4
3.43.43.43.43.43.43.43.43.43.43.43.43.43.43.43.43.43.43.43.43.43.45.45.45.45.45.45.45.45.45.45.45.45.45.45.45.45.45.45.45.45.45.45.45.45.45.45.45.45.45.45.45.45.4333333333333
DBD(g/cm3)
0.820.670.60.670.820.860.660.760.810.660.770.590.550.750.50.750.60.560.530.54
0.640.640.60.60.530.530.70.70.410.60.60.450.540.540.440.440.350.460.410.410.420.430.390.390.370.370.370.360.360.40.40.360.360.390.570.570.40.420.460.460.480,480.460.48
l0.40.40.450.430.440.440.440.410.450.450.440.460.420.420.470.470.50.480.480.480.5
IRD MAR(g/cm2/k.y.)
0.0740.2220.1960.0190.0280.1720.0350.0210.1140.0800.0310.0620.0790.0530.0030.0400.0330.0530.0000.001
0.0030.0110.0030.0010.0070.0070.0000.0000.0000.0000.0000.0000.0000.0000.0010.0010.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.1260.0000.0000.0010.0000.0000.0010.0000.0000.0040.0000.0000.0010.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0010.0000.0000.0550.0000.0000.0000.0000.0000.0000.0000.0000.000
188
LATE CENOZOIC ICE-RAFTING RECORDS
APPENDIX (continued).
Core, section,interval (cm)
36X-1, 84-8936X-2, 84-8936X-3, 11-1336X-3, 84-8936X-4, 84-8936X-5, 11-1336X-5, 84-8936X-6, 84-8936X-7, 12-14
145-883B-2H-1, 106-1082H-2, 106-1082H-3, 106-1082H-4, 106-1082H-5, 106-1082H-6, 106-1083H-1, 106-1083H-2, 106-1083H-3, 106-1083H-4, 106-1083H-5, 106-1083H-6, 106-1084H-1, 106-1084H-2, 106-1084H-3, 106-1084H-4, 106-1085H-1, 106-1085H-2, 106-1085H-3, 106-1085H-4, 106-1085H-5, 106-1086H-1, 106-1086H-2, 106-1086H-3, 106-1086H-4, 106-1086H-5, 106-1086H-6, 106-1087H-1, 105-1077H-2, 106-1087H-3, 106-1087H-4, 106-1087H-5, 106-1087H-6, 106-1088H-1, 106-1088H-2, 106-1088H-3, 106-1088H-4, 106-1088H-5, 106-1088H-6, 106-1089H-1, 106-1089H-2, 113-1159H-3, 106-1089H-4, 107-1099H-5, 106-1089H-6, 106-10810H-1, 106-10810H-2, 106-10810H-3, 106-10810H-4, 106-10811H-1, 106-10811H-2, 106-10811H-3, 106-10811H-4, 106-10811H-5, 106-10811H-6, 106-10812H-1, 106-10812H-2, 106-10812H-3, 106-10812H-4, 106-10812H-5, 106-10812H-6, 106-10813H-1, 106-10813H-2, 106-10813H-3, 106-10813H-4, 106-10813H-5, 106-10813H-6, 106-10814H-1, 107-10914H-2, 107-10914H-3, 107-10914H-4, 107-10914H-5, 107-10914H-6, 107-10915H-1, 107-10915H-2, 107-10915H-3, 107-10915H-4, 107-109
Depth(mbsf)
325.94327.44328.21328.94330.44331.21331.94333.44334.22
8.9610.4611.9613.4614.9616.4618.4619.9621.4622.9624.4625.9627.9629.4630.9632.4637.4638.9640.4641.9643.4646.9648.4649.9651.4652.9654.4656.4557.9659.4660.9662.4663.9665.9667.4668.9670.4671.9673.4675.4677.0378.4679.9781.4682.9684.9686.4687.9689.4694.4695.9697.4698.96
100.46101.96103.96105.46106.96108.46109.96111.46113.46114.96116.46117.96119.46120.96122.97124.47125.97127.47128.97130.47132.47133.97135.47136.97
Age(Ma,
calculated)
6.6986.7486.7746.7986.8486.8746.8986.9486.974
0.2680.3130.3580.4030.4480.4930.5530.5980.6430.6870.7320.7770.8370.8820.9270.9721.1221.1661.2111.2561.3011.4061.4511.4961.5411.5861.6311.6901.7351.7801.8251.8701.9151.9752.0202.0652.1102.1542.1992.2592.3062.3492.3942.4392.4842.5442.5892.6122.6282.6832.7002.7162.7332.7492.7652.7872.8042.8202.8372.8532.8702.8922.9082.9252.9412.9582.9742.9963.0133.0293.0463.0623.0793.1013.1173.1343.150
CSD(wt%)
0.270.180.160.090.160.180.150.000.22
0.901.300.730.290.780.101.001.160.860.400.471.151.950.510.841.122.311.890.860.541.036.242.250.450.220.130.290.141.121.431.751.450.231.09
1.045.701.140.150.500.080.520.300.560.380.050.371.330.571.071.131.491.250.491.770.811.210.490.760.650.490.210.690.811.361.700.420.281.011.270.360.771.760.260.750.531.24
IRD(vol%)
10.000.000.000.000.005.000.000.000.00
50.0030.0070.0010.0060.0070.0020.00
5.0030.0070.0020.000.00
10.0050.0080.0020.0020.0010.0040.0080.000.000.002.00
80.0040.0050.0080.0050.0020.0030.000.00
10.0080.0020.0030.000.000.00
10.0010.0035.005.000.002.00
40.000.000.000.000.000.000.000.000.000.000.000.000.000.002.000.000.000.000.000.000.000.000.000.000.000.000.002.000.000.000.000.000.000.00
IRD(wt%)
0.030.000.000.000.000.010.000.000.00
0.450.390.510.030.470.070.200.060.260.280.090.000.190.250.680.220.460.190.340.430.000.000.050.360.090.070.230.070.220.430.000.150.180.220.140.000.000.110.010.180.000.000.010.230.000.000.000.000.000.000.000.000.000.000.000.000.000.010.000.000.000.000.000.000.000.000.000.000.000.000.010.000.000.000.000.00
LSR(cm/k.y.)
333333333
3.33.33.33.33.33.33.33.33.33.33.33.33.33.33.33.33.33.33.33.33.33.33.33.33.33.33.33.33.33.33.33.33.33.33.33.33.33.33.33.33.33.33.33.33.33.33.39.19.19.19.19.19.19.19.19.19.19.19.19.19.19.19.19.19.19.19.19.19.19.19.19.19.19.19.19.19.1
DBD(g/cm3)
0.50.490.490.470.460.460.490.510.52
0.680.460.430.670.530.560.610.760.470.570.680.650.780.780.680.660.630.740.710.430.270.40.640.650.40.340.80.680.740.530.650.610.60.650.70.650.630.630.540.530.30.640.640.610.570.460.610.510.350.380.360.360.390.360.480.420.490.410.370.390.380.550.530.40.380.40.410.420.430.410.450.540.510.460.420.510.45
IRD MAR(g/cm2/k.y.)
0.0000.0000.0000.0000.0000.0000.0000.0000.000
0.0100.0060.0070.0010.0080.0010.0040.0010.0040.0050.0020.0000.0050.0070.0150.0050.0100.0050.0080.0060.0000.0000.0010.0080.0010.0010.0060.0020.0050.0080.0000.0030.0040.0050.0030.0000.0000.0020.0000.0030.0000.0000.0000.0050.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.000
189
L.A. KRISSEK
APPENDIX (continued).
AgeCore, section, Depth (Ma, CSD IRD IRD LSR DBD IRD MARinterval (cm) (mbsf) calculated) (wt%) (vol%) (wt%) (cm/k.y.) (g/cm3) (g/cm2/k.y.)
15H-5, 107-109 138.47 3.167 0.60 10.00 0.06 9.1 0.45 0.00216H-1, 106-108 141.96 3.205 1.42 0.00 0.00 9.1 0.45 0.00016H-2, 106-108 143.46 3.222 2.28 0.00 0.00 9.1 0.46 0.00016H-3, 106-108 144.96 3.238 1.19 0.00 0.00 9.1 0.58 0.00016H-4, 106-108 146.46 3.255 0.83 0.00 0.00 9.1 0.56 0.00016H-5, 106-108 147.96 3.271 1.06 0.00 0.00 9.1 0.46 0.00016H-6, 106-108 149.46 3.287 0.75 0.00 0.00 9.1 0.4 0.00017H-1, 106-108 151.46 3.309 1.32 0.00 0.00 9.1 0.37 0.00017H-2, 106-108 152.96 3.326 2.01 0.00 0.00 9.1 0.41 0.00017H-3, 106-108 154.46 3.342 1.41 0.00 0.00 9.1 0.55 0.00017H-4, 106-108 155.96 3.359 1.56 0.00 0.00 9.1 0.45 0.00017H-5, 106-108 157.46 3.375 2.21 0.00 0.00 9.1 0.47 0.00017H-6, 106-108 158.96 3.392 2.34 0.00 0.00 9.1 0.43 0.00018H-1, 106-108 160.96 3.414 0.47 0.00 0.00 9.1 0.77 0.00018H-2, 106-108 162.26 3.428 1.73 0.00 0.00 9.1 0.68 0.00018H-3, 106-108 163.76 3.445 0.59 0.00 0.00 9.1 0.6 0.00018H-4, 106-108 165.26 3.461 1.46 0.00 0.00 9.1 0.67 0.00018H-5, 106-108 166.76 3.478 0.47 0.00 0.00 9.1 0.53 0.00018H-6, 106-108 168.26 3.494 0.67 0.00 0.00 9.1 0.53 0.00019H-3, 106-108 173.46 3.551 0.47 0.00 0.00 9.1 0.51 0.00019H-5, 106-108 176.46 3.584 0.21 0.00 0.00 9.1 0.39 0.00020H-2, 106-108 181.46 3.639 0.39 0.00 0.00 9.1 0.45 0.00020H-5, 106-108 185.96 3.689 0.48 0.00 0.00 9.1 0.43 0.00021H-2, 106-108 190.96 3.744 0.71 0.00 0.00 9.1 0.45 0.00021H-5, 106-108 195.46 3.793 0.61 0.00 0.00 9.1 0.59 0.00022H-2, 107-109 200.47 3.848 0.25 0.00 0.00 9.1 0.46 0.00022H-5, 107-109 204.97 3.897 0.95 0.00 0.00 9.1 0.37 0.00023H-2, 106-108 209.96 3.952 0.59 0.00 0.00 9.1 0.5 0.00023H-5, 106-108 214.46 4.002 0.46 0.00 0.00 9.1 0.42 0.00025H-2, 106-108 228.96 4.161 1.40 0.00 0.00 9.1 0.48 0.00025H-5, 106-108 233.46 4.211 0.96 0.00 0.00 9.1 0.51 0.00026H-2, 106-108 238.46 4.265 0.28 0.00 0.00 9.1 0.6 0.00025H-5, 106-108 242.96 4.315 0.16 0.00 0.00 9.1 0.44 0.00027H-2, 106-108 247.96 4.370 0.15 0.00 0.00 9.1 0.46 0.00027H-5, 106-108 252.46 4.419 0.44 0.00 0.00 9.1 0.46 0.00028H-2, 107-109 257.47 4.474 0.12 0.00 0.00 9.1 0.42 0.00028H-5, 107-109 261.97 4.524 0.27 0.00 0.00 9.1 0.37 0.00029H-2, 106-108 266.96 4.579 0.08 0.00 0.00 9.1 0.41 0.00029H-5, 106-108 271.46 4.628 0.30 0.00 0.00 9.1 0.46 0.00030H-2, 106-108 276.46 4.683 0.64 0.00 0.00 9.1 0.46 0.00030H-5, 106-108 280.96 4.733 1.08 0.00 0.00 9.1 0.46 0.00031H-2, 106-108 285.96 4.787 0.20 0.00 0.00 9.1 0.44 0.00031H-5, 106-108 290.46 4.837 0.26 0.00 0.00 9.1 0.43 0.00032X-2, 106-108 295.46 4.892 0.13 0.00 0.00 9.1 0.59 0.00032X-5, 106-108 299.96 4.941 0.13 0.00 0.00 9.1 0.47 0.000
145-887A-1H-1, 15-17 0.15 0.003 0.15 10.00 0.02 5.36 0.43 0.0001H-1,65-67 0.65 0.012 4.69 5.00 0.23 5.36 0.43 0.0051H-1, 115-117 1.15 0.021 4.54 40.00 1.81 5.36 0.43 0.0421H-2, 15-17 1.65 0.031 2.50 100.00 2.50 5.36 0.7 0.0941H-2,65-67 2.15 0.040 5.73 100.00 5.73 5.36 0.7 0.2151H-2, 115-117 2.65 0.049 2.15 80.00 1.72 5.36 0.7 0.0651H-3, 15-17 3.15 0.059 3.17 2.00 0.06 5.36 0.91 0.0031H-3,65-67 3.65 0.068 0.60 30.00 0.18 5.36 0.91 0.0091H-3, 115-117 4.15 0.077 6.60 95.00 6.27 5.36 0.91 0.3061H-4, 15-17 4.65 0.087 4.27 100.00 4.27 5.36 0.21 0.0481H-4,65-67 5.15 0.096 0.25 10.00 0.03 5.36 0.21 0.0001H-4, 115-117 5.65 0.105 0.40 0.00 0.00 5.36 0.21 0.0001H-5, 15-17 6.15 0.115 1.53 100.00 1.53 5.36 0.36 0.0292H-1, 15-17 6.85 0.128 3.16 95.00 3.00 5.36 0.36 0.0582H-1,65-67 7.35 0.137 0.43 10.00 0.04 5.36 0.28 0.0012H-1, 115-117 7.85 0.146 0.31 0.00 0.00 5.36 0.28 0.0002H-2, 15-17 8.35 0.156 1.03 95.00 0.98 5.36 0.31 0.0162H-2,65-67 8.85 0.165 0.53 50.00 0.27 5.36 0.31 0.0042H-2, 115-117 9.35 0.174 1.71 95.00 1.63 5.36 0.31 0.0272H-3, 15-17 9.85 0.184 0.58 100.00 0.58 5.36 0.61 0.0192H-3,65-67 10.35 0.193 0.87 60.00 0.52 5.36 0.61 0.0172H-4, 15-17 11.35 0.212 0.21 100.00 0.21 5.36 0.8 0.0092H-4,65-67 11.85 0.221 1.39 85.00 1.18 5.36 0.8 0.0512H-4, 113-115 12.33 0.230 0.93 100.00 0.93 5.36 0.8 0.0402H-5, 15-17 12.85 0.240 9.46 100.00 9.46 5.36 0.82 0.4162H-5,65-67 13.35 0.249 2.26 100.00 2.26 5.36 0.82 0.0992H-5, 117-119 13.87 0.259 4.97 80.00 3.98 5.36 0.82 0.1752H-6, 15-17 14.35 0.268 0.95 30.00 0.29 5.36 1.02 0.0162H-6,65-67 14.85 0.277 14.35 100.00 14.35 5.36 1.02 0.7842H-6, 115-117 15.35 0.286 3.25 100.00 3.25 5.36 1.02 0.1782H-7, 15-17 15.85 0.296 0.67 100.00 0.67 5.36 0.7 0.0253H-1, 15-17 16.35 0.305 3.07 100.00 3.07 5.36 0.7 0.1153H-1,65-67 16.85 0.314 7.26 60.00 4.36 5.36 0.87 0.2033H-1, 115-117 17.35 0.324 3.64 100.00 3.64 5.36 0.87 0.1703H-2,8-10 17.78 0.332 2.20 100.00 2.20 5.36 0.71 0.0843H-2,65-67 18.35 0.342 0.12 50.00 0.06 5.36 0.71 0.0023H-2, 115-117 18.85 0.352 3.13 60.00 1.88 5.36 0.71 0.0713H-3, 15-17 19.35 0.361 1.31 70.00 0.92 5.36 1.09 0.0543H-3,62-64 19.82 0.370 1.51 100.00 1.51 5.36 1.09 0.0883H-3, 115-117 20.35 0.380 3.59 100.00 3.59 5.36 1.09 0.2103H-4, 15-17 20.85 0.389 1.27 60.00 0.76 5.36 0.62 0.025
190
LATE CENOZOIC ICE-RAFTING RECORDS
APPENDIX (continued).
AgeCore, section, Depth (Ma, CSD IRD IRD LSR DBD IRD MARinterval (cm) (mbsf) calculated) (wt%) (vol%) (wt%) (cm/k.y.) (g/cm3) (g/cm2/k.y.)
3H-4,62-64 21.31 0.398 1.82 100.00 1.82 5.36 0.62 0.0613H-4, 115-117 21.85 0.408 3.78 100.00 3.78 5.36 0.62 0.1263H-5, 15-17 22.35 0.417 2.71 60.00 1.63 5.36 1.01 0.0883H-5,62-64 22.82 0.426 4.01 80.00 3.21 5.36 1.01 0.1743H-5, 115-117 23.35 0.436 0.32 100.00 0.32 5.36 1.01 0.0173H-6, 15-17 23.85 0.445 1.93 90.00 1.74 5.36 0.99 0.0923H-6,62-64 24.32 0.454 1.98 100.00 1.98 5.36 0.99 0.1053H-6, 115-117 24.85 0.464 8.80 90.00 7.92 5.36 0.99 0.4203H-7, 15-17 25.35 0.473 3.34 100.00 3.34 5.36 0.9 0.1613H-7,62-64 25.82 0.482 3.58 100.00 3.58 5.36 0.9 0.1734H-1, 15-17 25.85 0.482 2.50 100.00 2.50 5.36 0.9 0.1214H-1,65-67 26.35 0.492 2.80 100.00 2.80 5.36 1.05 0.1584H-1, 115-117 26.85 0.501 3.23 100.00 3.23 5.36 1.05 0.1824H-2, 15-17 27.35 0.510 0.50 0.00 0.00 5.36 0.36 0.0004H-2,65-67 27.85 0.520 1.44 0.00 0.00 5.36 0.36 0.0004H-2, 115-117 28.35 0.529 0.05 30.00 0.01 5.36 0.36 0.0004H-3, 15-17 28.85 0.538 0.47 5.00 0.02 5.36 0.96 0.0014H-3,65-67 29.35 0.548 1.91 80.00 1.52 5.36 0.96 0.0784H-3, 115-117 29.85 0.557 3.79 100.00 3.79 5.36 0.96 0.1954H-4, 15-17 30.35 0.566 2.76 100.00 2.76 5.36 1.08 0.1604H-4,65-67 30.85 0.576 5.25 0.00 0.00 5.36 1.08 0.0004H-4, 115-117 31.35 0.585 7.04 100.00 7.04 5.36 1.08 0.4084H-5, 15-17 31.85 0.594 2.98 100.00 2.98 5.36 1.11 0.1774H-5,65-67 32.35 0.604 0.39 0.00 0.00 5.36 1.11 0.0004H-5, 115-117 32.85 0.613 0.61 100.00 0.61 5.36 1.11 0.0364H-6, 15-17 33.35 0.622 5.56 50.00 2.78 5.36 0.8 0.1194H-6,65-67 33.85 0.632 0.18 100.00 0.18 5.36 0.8 0.0084H-6, 115-117 34.35 0.641 0.15 40.00 0.06 5.36 0.8 0.0034H-7, 15-17 34.85 0.650 3.35 30.00 1.01 5.36 0.92 0.0505H-1, 15-17 35.35 0.660 0.13 90.00 0.12 5.36 0.92 0.0065H-1,65-67 35.85 0.669 0.08 20.00 0.02 5.36 0.4 0.0005H-1, 115-117 36.35 0.678 1.72 100.00 1.72 5.36 0.4 0.0375H-2, 15-17 36.85 0.688 4.98 95.00 4.73 5.36 0.76 0.1935H-2,65-67 37.35 0.697 0.23 100.00 0.23 5.36 0.76 0.0095H-2, 115-117 37.85 0.706 1.52 50.00 0.76 5.36 0.76 0.0315H-3, 15-17 38.35 0.715 3.58 100.00 3.58 5.36 0.79 0.1525H-3,62-64 38.82 0.724 3.08 100.00 3.08 5.36 0.79 0.1315H-3, 115-117 39.35 0.734 2.42 100.00 2.42 5.36 0.79 0.1035H-4, 15-17 39.85 0.743 3.73 95.00 3.55 5.36 0.42 0.0805H-4,65-67 40.35 0.753 1.26 100.00 1.26 5.36 0.42 0.0285H-4, 115-117 40.85 0.762 1.43 0.00 0.00 5.36 0.42 0.0005H-5, 15-17 41.35 0.771 1.11 100.00 1.11 5.36 0.8 0.0485H-5,65-67 41.85 0.781 1.15 0.00 0.00 5.36 0.8 0.0005H-5, 115-117 42.35 0.790 3.63 100.00 3.63 5.36 0.8 0.1565H-6, 15-17 42.85 0.799 26.76 0.00 0.00 5.36 0.47 0.0005H-6,65-67 43.35 0.809 1.56 100.00 1.56 5.36 0.47 0.0395H-6, 113-115 43.85 0.818 2.07 100.00 2.07 5.36 0.47 0.0525H-7, 15-17 44.35 0.827 6.50 100.00 6.50 5.36 0.9 0.3145H-7,65-67 44.85 0.837 8.13 100.00 8.13 5.36 0.9 0.3926H-1, 15-17 44.85 0.837 23.26 0.00 0.00 5.36 0.9 0.0006H-1,65-67 45.35 0.846 3.70 100.00 3.70 5.36 0.87 0.1736H-1, 115-117 45.85 0.855 4.20 100.00 4.20 5.36 0.87 0.1966H-2, 15-17 46.35 0.865 7.16 100.00 7.16 5.36 1.18 0.4536H-2,65-67 46.85 0.874 4.42 80.00 3.53 5.36 1.18 0.2246H-2, 115-117 47.35 0.883 3.77 98.00 3.69 5.36 1.18 0.2346H-3, 15-17 47.85 0.893 3.14 0.00 0.00 5.36 0.87 0.0006H-3,65-67 48.35 0.902 2.42 50.00 1.21 5.36 0.87 0.0566H-3, 115-117 48.85 0.911 2.54 100.00 2.54 5.36 0.87 0.1186H-4, 15-17 49.35 0.921 3.04 100.00 3.04 5.36 1.08 0.1766H-4,65-67 49.85 0.930 7.18 100.00 7.18 5.36 1.08 0.4156H-4, 115-117 50.35 0.939 0.81 50.00 0.40 5.36 1.08 0.0236H-5, 15-17 50.85 0.949 0.45 100.00 0.45 5.36 0.39 0.0096H-5,65-67 51.35 0.958 1.43 20.00 0.29 5.36 0.39 0.0066H-5, 115-117 51.85 0.967 2.89 75.00 2.16 5.36 0.39 0.0456H-6, 15-17 52.35 0.977 0.11 100.00 0.11 5.36 0.31 0.0026H-6,65-67 52.85 0.986 5.57 0.00 0.00 5.36 0.31 0.0006H-6, 115-117 53.35 0.995 2.13 10.00 0.21 5.36 0.31 0.0046H-7, 15-17 53.85 1.005 5.38 100.00 5.38 5.36 0.82 0.2366H-7,60-62 54.3 1.013 0.09 30.00 0.03 5.36 0.82 0.0017H-1, 14-16 54.34 1.014 1.54 100.00 1.54 5.36 0.82 0.0687H-1,63-65 54.83 1.023 3.81 100.00 3.81 5.36 0.95 0.1947H-1,115-117 55.35 1.033 3.56 80.00 2.85 5.36 0.95 0.1457H-2, 15-17 55.84 1.042 0.86 100.00 0.86 5.36 0.52 0.0247H-2,65-67 56.35 1.055 0.18 40.00 0.07 2 0.52 0.0017H-2, 115-117 56.85 1.080 2.26 65.00 1.47 2 0.52 0.0157H-3, 14-16 57.34 1.105 1.01 100.00 1.01 2 1.15 0.0237H-3,65-67 57.85 1.130 6.70 100.00 6.70 2 1.15 0.1547H-3, 115-117 58.35 1.155 3.76 100.00 3.76 2 1.15 0.0867H-4, 14-16 58.84 1.180 0.67 30.00 0.20 2 0.42 0.0027H-4,65-67 59.35 1.205 5.52 100.00 5.52 2 0.42 0.0467H-4, 115-117 59.85 1.230 3.60 100.00 3.60 2 0.42 0.0307H-5, 14-16 60.34 1.255 1.84 90.00 1.66 2 1.11 0.0377H-5,65-67 60.85 1.280 6.22 100.00 6.22 2 1.11 0.1387H-5, 115-117 61.35 1.305 5.75 100.00 5.75 2 1.11 0.1287H-6, 14-46 61.84 1.330 6.54 100.00 6.54 2 0.74 0.0977H-6,65-67 62.35 1.355 0.39 20.00 0.08 2 0.74 0.0017H-6, 115-117 62.85 1.380 1.18 70.00 0.83 2 0.74 0.0127H-7, 14-16 63.34 1.405 1.09 60.00 0.66 2 1.05 0.014
191
L.A. KRISSEK
APPENDIX (continued).
Core, section,interval (cm)
7H-7, 65-678H-1, 15-178H-1,65-678H-1, 115-1178H-2, 15-178H-2, 65-678H-2, 115-1178H-3, 15-178H-3, 67-698H-3, 115-1178H-4, 15-178H-4, 65-678H-4, 115-1178H-5, 15-178H-5, 65-678H-5, 115-1178H-6, 15-178H-6, 65-678H-6, 115-1178H-7, 15-178H-7, 65-678H-CC,15-179H-1, 15-179H-1,65-679H-1, 115-1179H-2, 15-179H-2, 65-679H-2, 115-1179H-3, 15-179H-3, 65-679H-3, 115-1179H-4, 15-179H-4, 65-679H-4, 115-1179H-5, 15-179H-5, 64-669H-5, 115-1179H-6, 15-1710H-1, 14-161 OH-1,65-6710H-1, 115-11710H-2, 15-1710H-2, 55-5710H-2, 115-11710H-3, 15-1710H-3, 65-6710H-3, 114-11610H-4, 15-1710H-4, 65-6710H-4, 115-11710H-5, 15-1710H-5, 65-6710H-5, 114-11610H-6, 15-1710H-6, 65-6710H-6, 115-11710H-7, 15-1711H-1, 14-46UH-1,65-6711H-1, 115-11711H-2, 14-1611H-2, 65-6711H-2, 115-117HH-3, 14-1611H-3, 65-6711H-3, 115-11711H-4, 14-1611H-4, 65-6711H-4, 115-11711H-5, 14-1611H-5, 65-6711H-5, 115-11711H-6, 14-1611H-6, 65-6711H-6, 115-11711H-7, 14-1611H-7, 65-6712H-1, 15-1712H-1,65-6712H-1, 115-11712H-2, 15-1712H-2, 65-6712H-2, 115-11712H-3, 15-1712H-3, 65-6712H-3, 115-11712H-4, 15-1712H-4, 65-67
Depth(mbsf)
63.8563.8564.3564.8565.3565.8566.3566.8567.3767.8568.3568.8569.3569.8570.3570.8571.3571.8572.3572.8573.3573.5573.3573.8574.3574.8575.3575.8576.3576.8577.3577.8578.3578.8579.3579.8580.3580.8582.8483.3583.8584.3584.7585.3585.8586.3586.8487.3587.8588.3588.8589.3589.8490.3590.8591.3591.8592.3492.8593.3593.8494.3594.8595.3495.8596.3596.8497.3597.8598.3498.8599.3599.84
100.35100.85101.34101.85101.85102.35102.85103.35103.85104.35104.85105.35105.85106.35106.85
Age(Ma,
calculated)
1.4301.430.455.480.505.530.555.580.606.630.655.680.705.730.755.780.805
1.8301.8551.8801.9051.915.905
1.9301.9551.9802.0052.0302.0552.0802.1052.1302.1552.1802.2052.2302.2552.2802.3802.4052.4302.4552.4752.5052.5302.5552.5802.6022.6212.6402.6592.6782.6972.7162.7352.7542.7732.7922.8112.8302.8492.8682.8872.9062.9252.9442.9632.9823.0013.0203.0393.0583.0773.0963.1153.1343.1533.1533.1723.1913.2103.2293.2483.2673.2863.3053.3243.343
CSD(wt%)
8.180.233.614.511.021.424.091.814.995.441.93
14.830.707.165.100.991.320.350.573.285.203.232.901.601.330.251.061.133.334.501.741.592.742.475.763.904.844.871.393.590.361.340.204.590.611.618.800.083.970.541.880.020.150.171.980.300.020.880.270.130.170.380.170.190.260.270.220.200.190.300.130.120.070.210.280.170.220.120.250.200.223.840.360.173.100.260.112.38
IRD(vol%)
100.0090.00
100.00100.0095.00
100.00100.0098.0080.0095.0070.00
100.0050.0050.0085.0095.00
100.0060.00
100.00100.0095.0095.0098.0098.00
100.0050.0070.0090.0095.0098.00
100.0095.00
100.0095.00
100.00100.0098.00
100.0040.00
100.0065.0060.0060.0095.0060.0065.0095.0090.0095.0060.0095.00
0.0050.0050.0070.0025.00
0.0065.00
0.000.000.000.000.000.000.000.000.000.000.000.000.000.00
10.0080.00
5.000.005.000.000.000.000.000.000.000.000.00
70.0010.000.00
IRD(wt%)
8.180.213.614.510.971.424.091.773.995.161.35
14.830.353.584.340.941.320.210.573.284.943.072.851.571.330.130.741.013.174.411.741.512.742.345.763.904.744.870.563.590.230.800.124.360.371.058.360.073.770.331.790.000.080.081.380.070.000.570.000.000.000.000.000.000.000.000.000.000.000.000.000.000.010.170.010.000.010.000.000.000.000.000.000.000.000.180.010.00
LSR(cm/k.y.)
222
λ2222222
222222222222222
22222222222222
22.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.63
:
DBD(g/cm3)
1.051.050.330.330.840.840.840.910.910.911.081.081.080.950.950.950.750.750.750.780.780.890.780.890.890.910.910.910.940.940.941.031.031.030.930.930.931.040.940.940.940.550.550.550.870.870.871.071.071.070.750.750.750.640.640.640.450.450.460.460.490.490.490.620.620.620.60.60.60.930.930.980.980.60.6
0.470.470.470.510.510.580.580.580.930.930.930.70.7
IRD MAR(g/cm2/k.y.)
0.1720.0040.0240.0300.0160.0240.0690.0320.0730.0940.0290.3200.0080.0680.0820.0180.0200.0030.0090.0510.0770.0550.0440.0280.0240.0020.0140.0180.0600.0830.0330.0310.0560.0480.1070.0730.0880.1010.0100.0670.0040.0090.0010.0480.0060.0180.1450.0020.1060.0090.0350.0000.0020.0010.0230.0010.0000.0070.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0030.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0040.0000.000
192
LATE CENOZOIC ICE-RAFTING RECORDS
APPENDIX (continued).
Core, section,interval (cm)
12H-4, 115-11712H-5, 15-1712H-5, 69-7112H-5, 115-11712H-6, 15-1712H-6, 65-6712H-6, 115-11712H-7, 15-1712H-7, 65-6713H-1, 15-1713H-1,65-6713H-1, 115-11713H-2, 15-1713H-2, 65-6713H-2, 115-11713H-3, 15-1713H-3, 65-6713H-3, 115-11713H-4, 15-1713H-4, 65-6713H-4, 115-11713H-5, 15-1713H-5, 65-6713H-5, 115-11713H-6, 15-1713H-6, 65-6713H-6, 115-11713H-7, 15-1713H-7, 65-6714H-1, 15-1714H-1, 65-6714H-1, 115-11714H-2, 15-1714H-2, 65-6714H-2, 115-11714H-3, 15-1714H-3, 69-7114H-3, 115-11714H-4, 15-1714H-4, 65-6714H-4, 115-11714H-5, 15-1714H-5, 65-6714H-5, 115-11714H-6, 15-1714H-6, 65-6714H-6, 115-11714H-7, 15-1715X-1, 15-1715X-1,65-6715X-1, 115-11715X-2, 15-1715X-2, 65-6715X-2, 115-11715X-3, 15-1715X-3, 65-6715X-3, 115-11715X-4, 15-1715X-4, 65-6715X-4, 115-11715X-5, 15-1715X-5, 65-6715X-5, 115-11715X-6, 15-1716X-1, 15-1716X-1, 61-6316X-1, 115-11716X-2, 15-1716X-2, 61-6316X-2, 115-11716X-3, 19-2116X-3, 61-6316X-3, 115-11717X-1, 15-1717X-1, 65-6717X-1, 115-11717X-2, 15-1717X-2, 65-6717X-2, 115-11717X-3, 15-1717X-3, 65-6717X-3, 115-11717X-4, 15-1717X-4, 65-6717X-4, 115-11717X-5, 15-1717X-5, 65-6717X-5, 115-117
Depth(mbsf)
107.35107.85108.39108.85109.35109.85110.35110.85111.35111.35111.85112.35112.85113.35113.85114.35114.85115.35115.85116.35116.85117.35117.85118.35118.85119.35119.85120.35120.85120.85121.35121.85122.35122.85123.35123.85124.39124.85125.35125.85126.35126.85127.35127.85128.35128.85129.35129.85130.35130.85131.35131.85132.35132.85133.35133.85134.35134.85135.35135.85136.35136.85137.35137.85139.85140.31140.85141.35141.81142.35142.89143.31143.85145.25145.75146.25146.75147.25147.75148.25148.75149.25149.75150.25150.75151.25151.75152.25
Age(Ma,
calculated)
3.3623.3813.4023.4193.4383.4573.4763.4953.5143.5143.5333.5523.5713.5903.6103.6293.6483.6673.6863.7053.7243.7433.7623.7813.8003.8193.8383.8573.8763.8763.8953.9143.9333.9523.9713.9904.0104.0284.0474.0664.0854.1044.1234.1424.1614.1804.1994.2184.2374.2564.2754.2944.3134.3324.3514.3704.3894.4084.4274.4464.4654.4844.5034.5224.5984.6164.6364.6554.6734.6934.7144.7304.7504.8034.8224.8414.8604.8794.8984.9174.9374.9564.9754.9945.0135.0325.0515.070
CSD(wt%)
0.140.110.282.500.220.370.300.323.241.160.180.080.110.270.130.080.240.210.100.250.140.280.140.070.250.110.120.320.150.280.130.140.290.480.210.130.100.190.160.240.220.160.210.040.250.190.190.160.270.160.000.220.270.150.150.180.180.130.290.150.170.190.130.230.160.270.200.150.280.200.200.320.320.280.170.300.190.150.210.240.300.150.150.210.220.120.360.19
IRD(vol%)
10.0020.000.000.000.002.002.000.005.00
80.000.005.002.00HUI)5.005.000.000.000.000.000.002.002.003.002.000.002.002.005.00
60.0040.0035.00
3.002.000.000.000.003.000.000.000.000.003.000.000.000.000.000.00
10.000.000.005.005.003.002.000.003.00
10.005.000.000.000.000.000.000.000.000.003.003.000.000.000.00
10.000.003.002.000.000.00
20.005.000.000.000.000.000.000.000.000.00
IRD(wt%)
0.010.020.000.000.000.010.010.000.160.930.000.000.000.000.010.000.000.000.000.000.000.010.000.000.000.000.000.010.010.170.050.050.010.010.000.000.000.010.000.000.000.000.010.000.000.00().()()o!oo0.030.000.000.010.010.000.000.000.010.010.010.000.000.000.00().()()0.000.000.000.000.010.000.000.000.030.000.010.010.000.000.040.010.000.00().()()0.000.000.000.000.00
LSR(cm/k.y.)
2.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.632.63
DBD(g/cm3)
0.70.830.830.830.520.520.520.540.540.540.530.530.460.460.460.530.530.530.540.540.540.480.480.480.490.490.490.480.480.480.450.450.510.510.510.50.50.50.490.520.520.450.450.450.460.460.460.440.440.420.420.40.40.40.430.430.430.460.460.460.410.410.410.470.440.440.440.440.440.440.440.440.440.480.480.480.530.530.530.450.450.450.410.410.410.420.420.42
IRD MAR(g/cm2/k.y.)
0.0000.0010.0000.0000.0000.0000.0000.0000.0020.0130.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0020.0010.0010.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0010.0000.0000.0000.0000.0000.0000.0000.0000.000
193
L.A. KRISSEK
APPENDIX (continued).
Core, section,interval (cm)
18X-1, 15-1718X-1,65-6718X-1, 115-11718X-2, 15-1718X-2, 65-6718X-2, 115-11718X-3, 15-1718X-3, 65-6718X-3, 115-11718X-4, 15-1718X-4, 65-6718X-4, 115-11718X-5, 15-1718X-5, 65-6718X-5, 115-11718X-6, 15-1718X-6, 65-67
Depth(mbsf)
154.95155.45155.95156.45156.95157.45157.95158.45158.95159.45159.95160.45160.95161.45161.95162.45162.95
Age(Ma,
calculated)
5.1725.1915.2105.2295.2485.2675.2865.3055.3245.3435.3625.3815.4005.4195.4385.4575.476
CSD(wt%)
0.430.160.100.350.120.110.210.150.090.140.111.120.040.180.160.200.31
IRD(vol%)
50.000.000.003.000.000.000.000.000.00
30.0010.002.00
10.0070.0020.000.000.00
IRD(wt%)
0.210.000.000.010.000.000.000.000.000.040.010.020.000.120.030.000.00
LSR(cm/k.y.)
2.632.632.632.63
2.632.632.632.632.632.632.632.632.632.632.632.63
DBD(g/cm3)
0.460.460.460.420.420.420.50.50.50.460.460.460.560.560.560.40.4
IRD MAR(g/cm2/k.y.)
0.0030.0000.0000.0000.0000.0000.0000.0000.0000.0010.0000.0000.0000.0020.0000.0000.000
Note: CSD = abundance of the total coarse-sand fraction. IRD = abundance of IRD in the coarse-sand fraction. IRD = abundance of coarse sand-sized IRD in the total sample. LSR :average linear sedimentation rate. DBD = sediment dry-bulk density. IRD MAR = mass accumulation rate of coarse sand-sized IRD.
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