http://lod.bco-dmo.org/id/dataset/865386
eng; USA
utf8
dataset
Highest level of data collection, from a common set of sensors or instrumentation, usually within the same research project
Biological and Chemical Oceanography Data Management Office (BCO-DMO)
Unavailable
508-289-2009
WHOI MS#36
Woods Hole
MA
02543
USA
info@bco-dmo.org
http://www.bco-dmo.org
Monday - Friday 8:00am - 5:00pm
For questions regarding this resource, please contact BCO-DMO via the email address provided.
pointOfContact
2021-11-23
ISO 19115-2 Geographic Information - Metadata - Part 2: Extensions for Imagery and Gridded Data
ISO 19115-2:2009(E)
Major (Al), minor (Mn, Ba), and trace metal (Cd, Ag, Mo) data from Multitracers sediment trap samples
2023-10-25
publication
2023-10-25
revision
Marine Biological Laboratory/Woods Hole Oceanographic Institution Library (MBLWHOI DLA)
2023-10-25
publication
https://doi.org/10.26008/1912/bco-dmo.865386.1
Jennifer McKay
Oregon State University
principalInvestigator
Biological and Chemical Oceanography Data Management Office (BCO-DMO)
Unavailable
508-289-2009
WHOI MS#36
Woods Hole
MA
02543
USA
info@bco-dmo.org
http://www.bco-dmo.org
Monday - Friday 8:00am - 5:00pm
For questions regarding this resource, please contact BCO-DMO via the email address provided.
publisher
Cite this dataset as: McKay, J. (2023) Major (Al), minor (Mn, Ba), and trace metal (Cd, Ag, Mo) data from Multitracers sediment trap samples. Biological and Chemical Oceanography Data Management Office (BCO-DMO). (Version 1) Version Date 2023-10-25 [if applicable, indicate subset used]. doi:10.26008/1912/bco-dmo.865386.1 [access date]
Multitracers Metal Concentration Data Dataset Description: Methods and Sampling: <p>The following methodology section is from McKay (in prep), with minor modifications.</p>
<p><strong>Sample collection</strong><br />
During the Multitracers Project (September 1987 to July 1991) bottom-moored sediments traps were deployed at three stations (Nearshore, Midway, and Gyre) in the Northeast Pacific Ocean. This dataset provides major (Al), minor (Ti, Ba, Mn), and trace element (Cd, Ag, Mo) data for the Nearshore and Gyre stations. The data are for the first 2 years of the project, where "year" refers to the time a trap mooring was deployed until it was recovered and not a calendar year (e.g., Year 1 is September 1987 to September 1988 and Year 2 is September 1988 to September 1989). In addition, there are data for the Nearshore site in Year 3 (September 1989 and March 1990). Sediment trap samples were obtained from the Oregon State University Marine and Geology Repository.</p>
<p>Each mooring had sediment traps deployed at 500 m (Year 1 only), within the OMZ at 1000 m, just below the OMZ at 1500 and/or 1750 m, and 500 m above the bottom (near-bottom traps; ~2300 m at the Nearshore site and ~3200 m at the Gyre site). In Years 1 and 2 most traps, with the exception of the 1500 m trap, had 6 sample cups (C1 to C6) that were open for 30 to 33 days (C1), 60 days (C2 to C5), and 87 to 94 days (C6). The 1500 m trap at both sites had 13 cups that were open for ~30 days each. In Year 3 all Nearshore traps had 6 cups, which were open for 30 days (C1 to C5) and 23 days (C6, near-bottom trap only). No traps were deployed at the Gyre site in Year 3.</p>
<p>In Year 1 the 500 m trap at the Nearshore station failed after the third cup, presumably due to clogging during a high flux event. There is also evidence that the 500 m trap at the Gyre site under-collected material (i.e., lower fluxes at 500 m compared to 1000 m). For these reasons, the 500 m traps were not deployed at either site in subsequent years. The 1500 m traps also failed at both sites in Year 1. Fortunately, traps were also deployed at 1750 m and they functioned correctly.</p>
<p>The trap sample cups were filled with unfiltered seawater collected from the near-bottom trap depth at each site and poisoned with 15g/L of sodium azide. To compare the effects of different "preservatives" a pair of traps were deployed at the Nearshore site (1750 m) in Year 3; one set of cups was poisoned with sodium azide and the others preserved with formalin. No special trace metal clean sampling procedures were utilized during the Mulitracers Project; however, the traps were constructed out of plastic and fiberglass thus reducing possible trace metal contamination.</p>
<p>When the sediment traps were recovered the sample cups were removed, sealed, and not opened until they were ready to be processed in the laboratory. Once back at the lab the samples were allowed to sit undisturbed until the particulate material had settled. Once opened the supernatant was poured off and then used to rinse the particulate fraction through a 2 mm sieve. The ≥2 mm size-fraction was transferred to a bottle containing formalin and refrigerated for future use. The &lt;2 mm size-fraction, which was used in this study, was split into 10 aliquots. Between 1 and 4 aliquots were frozen for future use. The other 6 to 9 aliquots were centrifuged and the supernatant was discarded. These samples were then rinsed with buffered distilled water and centrifuged; this step was carried out twice. Finally, the samples were freeze-dried and then homogenized.</p>
<p><strong>Analytical methods</strong><br />
Sample preparation for major (Al), minor (Mn, Ba), and trace (Cd, Ag, Mo) metal analysis involved placing ~50 mg of sample into teflon reaction vessels and pretreating overnight at room temperature with a mixture of concentrated, quartz-distilled HNO<sub>3</sub> (1 ml) and HCl (1 ml). The following day concentrated, quartz-distilled HNO<sub>3 </sub>(2 ml), BDH Aristar Ultra HF (2 ml), and Milli-Q water (2 ml) were added and the samples were digested using a CEM MARS microwave digestion system. This was followed by 3 cycles of acid evaporation using the same system. After the final evaporation, samples were diluted with 10 ml of 5% quartz-distilled HNO<sub>3</sub> and heated for 24 hr at 60°C to remove fluorides complexes (Muratli et al., 2012) The concentrations of Ag, Cd, and Mo in these digests were analyzed by Inductively Coupled Plasma Mass Spectrometry (ICP-MS) using a Thermo Scientific X-Series II instrument located in the Keck Collaboratory at Oregon State University. No column chemistry was carried out prior to ICP-MS analysis. Instead, a collision cell was utilized to reduce the formation of oxides that interfere with the analysis of Ag-109 (Nb oxides and Zr oxides and oxyhydroxides) and Cd-114 (Sn oxides). However, it was still necessary to measure the oxide formation, which was typically &lt;5 %, and apply a small oxide correction to the data. The same digests were used to analyze the major and minor element concentrations by ICP-OES (Prodigy, Teledyne Instruments) in the Keck Collaboratory. Metal concentrations were calculated using an external standard calibration curve.</p>
<p>Precision and accuracy were determined using the National Research Council of Canada sediment standards MESS-3 and PACS-2, which were put through the same digestion and analytical procedures as the samples. In general, precision was better than 8% and accuracy was within error for all metals except Al (see the "Table 1" <a href="https://datadocs.bco-dmo.org/docs/305/Ag_Flux_and_Export_Productivity/data_docs/865386/Table1.pdf" target="_blank">Supplemental File</a> (PDF)). The Al values for both sediment standards are slightly (~4 to 5 %) lower than their certified values.</p>
<p>The non-lithogenic (i.e., excess) concentrations of the metals were estimated using Eq. (1), where xsM is the excess concentration of the metal, M<sub>smpl</sub> is the metal concentration in the sample, Al<sub>smpl</sub> is the aluminum concentration in the sample, and (M/Al)<sub>lith</sub> is the metal/Al ratio in lithogenic material.</p>
<p>[xsM] = [M<sub>smpl</sub>] – [Al<sub>smpl</sub>] * (M/Al)<sub>lith</sub></p>
<p>This method of calculating excess concentrations relies on measuring or assuming a reasonable lithogenic value for each metal. In this study, the average shale values reported in Brumsack (2006) were used (i.e., 8.83 wt% Al; 580 µg/g Ba; 850 µg/g Mn; 0.13 µg/g Cd; 0.07 µg/g Ag; 1 µg/g Mo). In addition, because variations in trace metal concentrations can be driven by changes in the concentrations of major components (e.g., dilution by lithogenic material in late fall and winter) all metal data have been converted from concentrations to fluxes using the total particulate flux data provided by Dr. Collier.</p>
<p><strong>Known problems/issues</strong><br />
(1) Year 1 data for the 500 m sediment traps at both sites (i.e., Nearshore samples MT31584 to MT31586 and Gyre samples MT31607 to MT31612) are problematic because evidence (e.g., lower total mass fluxes compared to the 1000 m trap) suggest these shallow traps under-collected settling particulate material.</p>
<p>(2) The 1500 m trap at the Nearshore site in Year 1 (samples MT31396 to MT31401) should have had samples for 13 cups; however, only 6 samples were collected. It is unclear whether the trap failed after cup 6, meaning this cup was open for 237 days, or the trap was programmed improperly and thus each cup was actually open for twice as long. Flux data suggest the latter.</p>
<p>(3) At times fluxes were low and not enough sample was available for an analysis. This was most common at the Gyre site.</p>
<p>(4) The midway (MS) sediment trap samples were not analyzed as a part of this study. Also, there was no Gyre sediment trap samples collected in Year 3.</p>
Funding provided by NSF Division of Ocean Sciences (NSF OCE) Award Number: OCE-1234465 Award URL: https://www.nsf.gov/awardsearch/show-award?AWD_ID=1234465
completed
Jennifer McKay
Oregon State University
541-737-1203
104 CEOAS Admin Building
Corvallis
OR
97330
USA
jennifer.mckay@oregonstate.edu
pointOfContact
asNeeded
Dataset Version: 1
Unknown
Sample_ID
Sample_Description
Mooring_ID
Sample_Type
Latitude
Longitude
Water_Depth
Trap_Depth
Cup_num
Date_Cup_Opened
Days_Cup_Open
Cup_vol
Area
Wt_in_cup
Wt_Fract
Total_Flux_mg_cm2_y
Total_Flux_mg_m2_d
Al
Ti
Ba
Mn
Mo
Ag
Cd
Total_Al_flux
Total_Ti_flux
Total_Ba_flux
Total_Mn_flux
Total_Mo_flux
Total_Ag_flux
Total_Cd_flux
Excess_Ba_flux
Excess_Mn_flux
Excess_Mo_flux
Excess_Ag_flux
Excess_Cd_flux
Thermo Scientific X-Series II Inductively Coupled Plasma Mass Spectrometer
Teledyne Instruments, Prodigy Inductively Coupled Plasma - Optical Emission Spectrometer
bottom-moored sediment traps
theme
None, User defined
sample identification
sample description
mooring identification
sample type
latitude
longitude
depth_w
depth
sample cup number
date
time_elapsed
volume
surface_area
weight
flux
Aluminum
Titanium
Barium
Manganese
Molybdenum
trace metal concentration
Cadmium
featureType
BCO-DMO Standard Parameters
Inductively Coupled Plasma Mass Spectrometer
Inductively Coupled Plasma Optical Emission Spectrometer
Sediment Trap
instrument
BCO-DMO Standard Instruments
otherRestrictions
otherRestrictions
Access Constraints: none. Use Constraints: Please follow guidelines at: http://www.bco-dmo.org/terms-use Distribution liability: Under no circumstances shall BCO-DMO be liable for any direct, incidental, special, consequential, indirect, or punitive damages that result from the use of, or the inability to use, the materials in this data submission. If you are dissatisfied with any materials in this data submission your sole and exclusive remedy is to discontinue use.
A Sediment Trap Study to Determine if the Flux of Silver to the Seafloor is Related to Export Productivity
https://osprey.bco-dmo.org/project/849239
A Sediment Trap Study to Determine if the Flux of Silver to the Seafloor is Related to Export Productivity
<p><em>NSF Award Abstract:</em><br />
Intellectual Merit: Since work conducted in the early 1980's, there has been a growing interest in improving our understanding of the relationship between the particle flux of Ag and export productivity in the ocean. Despite tantalizing positive correlations between sedimentary Ag and more traditional paleoproxies, such as organic carbon, opal and biogenic Ba, there has yet to be a comprehensive study undertaken to evaluate in detail the relationship between the flux of particulate Ag and export productivity in the ocean. If the sinking flux of Ag can be shown to reliably track export productivity, as will be evaluated in this study, then the geochemical community will have a new tracer to provide important new insights and constraints on past changes in paleoproductivity. In particular, this project will test the hypothesis that Ag can be used to trace the flux of biogenic particulate organic matter exported from the surface ocean to the sediments; furthermore, this project will evaluate the potential use of Ag as a proxy tracer of past changes in productivity. A secondary objective is to determine whether sedimentary redox conditions affect the accumulation of Ag in sediments. This work will be accomplished by analysis of Ag in a suite of archived sediment trap and sediment samples collected from a range of oceanographic locations. The data obtained from this research will aid in the development of a new paleoproductivity proxy (Ag) that can be utilized to improve paleoceanographic reconstructions.</p>
<p>Broader Impacts: In regards to broader impacts, this research will provide the scientific community with a better understanding of the biogeochemical cycling of Ag, an element that is toxic to marine organisms, as well as the cycling of redox-sensitive trace metals. The study will support an early scientist, and provide training for one graduate student and two undergraduate students.</p>
Ag Flux and Export Productivity
largerWorkCitation
project
eng; USA
oceans
-132
-125.761
40.087
42.192
1987-09-22
1990-09-17
0
BCO-DMO catalogue of parameters from Major (Al), minor (Mn, Ba), and trace metal (Cd, Ag, Mo) data from Multitracers sediment trap samples
Biological and Chemical Oceanography Data Management Office (BCO-DMO)
Unavailable
508-289-2009
WHOI MS#36
Woods Hole
MA
02543
USA
info@bco-dmo.org
http://www.bco-dmo.org
Monday - Friday 8:00am - 5:00pm
For questions regarding this resource, please contact BCO-DMO via the email address provided.
pointOfContact
http://lod.bco-dmo.org/id/dataset-parameter/865442.rdf
Name: Sample_ID
Units: unitless
Description: <p>sample identifier</p>
http://lod.bco-dmo.org/id/dataset-parameter/865443.rdf
Name: Sample_Description
Units: unitless
Description: <p>sample description</p>
http://lod.bco-dmo.org/id/dataset-parameter/865444.rdf
Name: Mooring_ID
Units: unitless
Description: <p>mooring identifier</p>
http://lod.bco-dmo.org/id/dataset-parameter/865445.rdf
Name: Sample_Type
Units: unitless
Description: <p>sample type</p>
http://lod.bco-dmo.org/id/dataset-parameter/865446.rdf
Name: Latitude
Units: degrees North
Description: <p>latitude</p>
http://lod.bco-dmo.org/id/dataset-parameter/865447.rdf
Name: Longitude
Units: degrees East
Description: <p>longitude</p>
http://lod.bco-dmo.org/id/dataset-parameter/865448.rdf
Name: Water_Depth
Units: meters (m)
Description: <p>water depth</p>
http://lod.bco-dmo.org/id/dataset-parameter/865449.rdf
Name: Trap_Depth
Units: meters (m)
Description: <p>trap depth</p>
http://lod.bco-dmo.org/id/dataset-parameter/865450.rdf
Name: Cup_num
Units: unitless
Description: <p>cup number</p>
http://lod.bco-dmo.org/id/dataset-parameter/865451.rdf
Name: Date_Cup_Opened
Units: unitless
Description: <p>date when cup was opened; format: YYYY-MM-DD</p>
http://lod.bco-dmo.org/id/dataset-parameter/865452.rdf
Name: Days_Cup_Open
Units: days
Description: <p>number of days cup was open</p>
http://lod.bco-dmo.org/id/dataset-parameter/865453.rdf
Name: Cup_vol
Units: milliliters (ml)
Description: <p>cup volume</p>
http://lod.bco-dmo.org/id/dataset-parameter/865454.rdf
Name: Area
Units: square meters (m2)
Description: <p>area</p>
http://lod.bco-dmo.org/id/dataset-parameter/865455.rdf
Name: Wt_in_cup
Units: grams (g)
Description: <p>weight in cup</p>
http://lod.bco-dmo.org/id/dataset-parameter/865456.rdf
Name: Wt_Fract
Units: unitless
Description: <p>weight fraction</p>
http://lod.bco-dmo.org/id/dataset-parameter/865457.rdf
Name: Total_Flux_mg_cm2_y
Units: milligrams per square centimeter per year (mg/cm2/y)
Description: <p>total flux</p>
http://lod.bco-dmo.org/id/dataset-parameter/865458.rdf
Name: Total_Flux_mg_m2_d
Units: milligrams per square meter per day (mg/m2/d)
Description: <p>total flux</p>
http://lod.bco-dmo.org/id/dataset-parameter/865459.rdf
Name: Al
Units: wt percent
Description: <p>aluminum (Al) percent weight</p>
http://lod.bco-dmo.org/id/dataset-parameter/865460.rdf
Name: Ti
Units: wt percent
Description: <p>titanium (Ti) percent weight</p>
http://lod.bco-dmo.org/id/dataset-parameter/865461.rdf
Name: Ba
Units: micrograms per gram (ug/g)
Description: <p>barium (Ba) concentration</p>
http://lod.bco-dmo.org/id/dataset-parameter/865462.rdf
Name: Mn
Units: micrograms per gram (ug/g)
Description: <p>manganese (Mn) concentration</p>
http://lod.bco-dmo.org/id/dataset-parameter/865463.rdf
Name: Mo
Units: micrograms per gram (ug/g)
Description: <p>molybdenum (Mo) concentration</p>
http://lod.bco-dmo.org/id/dataset-parameter/865464.rdf
Name: Ag
Units: micrograms per gram (ug/g)
Description: <p>silver (Ag) concentration</p>
http://lod.bco-dmo.org/id/dataset-parameter/865465.rdf
Name: Cd
Units: micrograms per gram (ug/g)
Description: <p>cadmium (Cd) concentration</p>
http://lod.bco-dmo.org/id/dataset-parameter/865466.rdf
Name: Total_Al_flux
Units: milligrams per square meter per day (mg/m2/d)
Description: <p>total Al flux</p>
http://lod.bco-dmo.org/id/dataset-parameter/865467.rdf
Name: Total_Ti_flux
Units: milligrams per square meter per day (mg/m2/d)
Description: <p>total Ti flux</p>
http://lod.bco-dmo.org/id/dataset-parameter/865468.rdf
Name: Total_Ba_flux
Units: micrograms per square meter per day (ug/m2/d)
Description: <p>total Ba flux</p>
http://lod.bco-dmo.org/id/dataset-parameter/865469.rdf
Name: Total_Mn_flux
Units: micrograms per square meter per day (ug/m2/d)
Description: <p>total Mn flux</p>
http://lod.bco-dmo.org/id/dataset-parameter/865470.rdf
Name: Total_Mo_flux
Units: micrograms per square meter per day (ug/m2/d)
Description: <p>total Mo flux</p>
http://lod.bco-dmo.org/id/dataset-parameter/865471.rdf
Name: Total_Ag_flux
Units: nanograms per square meter per day (ng/m2/d)
Description: <p>total Ag flux</p>
http://lod.bco-dmo.org/id/dataset-parameter/865472.rdf
Name: Total_Cd_flux
Units: nanograms per square meter per day (ng/m2/d)
Description: <p>total Cd flux</p>
http://lod.bco-dmo.org/id/dataset-parameter/865473.rdf
Name: Excess_Ba_flux
Units: micrograms per square meter per day (ug/m2/d)
Description: <p>excess Ba flux</p>
http://lod.bco-dmo.org/id/dataset-parameter/865474.rdf
Name: Excess_Mn_flux
Units: micrograms per square meter per day (ug/m2/d)
Description: <p>excess Mn flux</p>
http://lod.bco-dmo.org/id/dataset-parameter/865475.rdf
Name: Excess_Mo_flux
Units: nanograms per square meter per day (ng/m2/d)
Description: <p>excess Mo flux</p>
http://lod.bco-dmo.org/id/dataset-parameter/865476.rdf
Name: Excess_Ag_flux
Units: nanograms per square meter per day (ng/m2/d)
Description: <p>excess Ag flux</p>
http://lod.bco-dmo.org/id/dataset-parameter/865477.rdf
Name: Excess_Cd_flux
Units: nanograms per square meter per day (ng/m2/d)
Description: <p>excess Cd flux</p>
GB/NERC/BODC > British Oceanographic Data Centre, Natural Environment Research Council, United Kingdom
Biological and Chemical Oceanography Data Management Office (BCO-DMO)
Unavailable
508-289-2009
WHOI MS#36
Woods Hole
MA
02543
USA
info@bco-dmo.org
http://www.bco-dmo.org
Monday - Friday 8:00am - 5:00pm
For questions regarding this resource, please contact BCO-DMO via the email address provided.
pointOfContact
32153
https://darchive.mblwhoilibrary.org/server/api/core/bitstreams/9b208926-ae2b-46cd-aeb5-a55e30b35baa/content
download
https://doi.org/10.26008/1912/bco-dmo.865386.1
download
onLine
dataset
<p>The following methodology section is from McKay (in prep), with minor modifications.</p>
<p><strong>Sample collection</strong><br />
During the Multitracers Project (September 1987 to July 1991) bottom-moored sediments traps were deployed at three stations (Nearshore, Midway, and Gyre) in the Northeast Pacific Ocean. This dataset provides major (Al), minor (Ti, Ba, Mn), and trace element (Cd, Ag, Mo) data for the Nearshore and Gyre stations. The data are for the first 2 years of the project, where "year" refers to the time a trap mooring was deployed until it was recovered and not a calendar year (e.g., Year 1 is September 1987 to September 1988 and Year 2 is September 1988 to September 1989). In addition, there are data for the Nearshore site in Year 3 (September 1989 and March 1990). Sediment trap samples were obtained from the Oregon State University Marine and Geology Repository.</p>
<p>Each mooring had sediment traps deployed at 500 m (Year 1 only), within the OMZ at 1000 m, just below the OMZ at 1500 and/or 1750 m, and 500 m above the bottom (near-bottom traps; ~2300 m at the Nearshore site and ~3200 m at the Gyre site). In Years 1 and 2 most traps, with the exception of the 1500 m trap, had 6 sample cups (C1 to C6) that were open for 30 to 33 days (C1), 60 days (C2 to C5), and 87 to 94 days (C6). The 1500 m trap at both sites had 13 cups that were open for ~30 days each. In Year 3 all Nearshore traps had 6 cups, which were open for 30 days (C1 to C5) and 23 days (C6, near-bottom trap only). No traps were deployed at the Gyre site in Year 3.</p>
<p>In Year 1 the 500 m trap at the Nearshore station failed after the third cup, presumably due to clogging during a high flux event. There is also evidence that the 500 m trap at the Gyre site under-collected material (i.e., lower fluxes at 500 m compared to 1000 m). For these reasons, the 500 m traps were not deployed at either site in subsequent years. The 1500 m traps also failed at both sites in Year 1. Fortunately, traps were also deployed at 1750 m and they functioned correctly.</p>
<p>The trap sample cups were filled with unfiltered seawater collected from the near-bottom trap depth at each site and poisoned with 15g/L of sodium azide. To compare the effects of different "preservatives" a pair of traps were deployed at the Nearshore site (1750 m) in Year 3; one set of cups was poisoned with sodium azide and the others preserved with formalin. No special trace metal clean sampling procedures were utilized during the Mulitracers Project; however, the traps were constructed out of plastic and fiberglass thus reducing possible trace metal contamination.</p>
<p>When the sediment traps were recovered the sample cups were removed, sealed, and not opened until they were ready to be processed in the laboratory. Once back at the lab the samples were allowed to sit undisturbed until the particulate material had settled. Once opened the supernatant was poured off and then used to rinse the particulate fraction through a 2 mm sieve. The ≥2 mm size-fraction was transferred to a bottle containing formalin and refrigerated for future use. The &lt;2 mm size-fraction, which was used in this study, was split into 10 aliquots. Between 1 and 4 aliquots were frozen for future use. The other 6 to 9 aliquots were centrifuged and the supernatant was discarded. These samples were then rinsed with buffered distilled water and centrifuged; this step was carried out twice. Finally, the samples were freeze-dried and then homogenized.</p>
<p><strong>Analytical methods</strong><br />
Sample preparation for major (Al), minor (Mn, Ba), and trace (Cd, Ag, Mo) metal analysis involved placing ~50 mg of sample into teflon reaction vessels and pretreating overnight at room temperature with a mixture of concentrated, quartz-distilled HNO<sub>3</sub> (1 ml) and HCl (1 ml). The following day concentrated, quartz-distilled HNO<sub>3 </sub>(2 ml), BDH Aristar Ultra HF (2 ml), and Milli-Q water (2 ml) were added and the samples were digested using a CEM MARS microwave digestion system. This was followed by 3 cycles of acid evaporation using the same system. After the final evaporation, samples were diluted with 10 ml of 5% quartz-distilled HNO<sub>3</sub> and heated for 24 hr at 60°C to remove fluorides complexes (Muratli et al., 2012) The concentrations of Ag, Cd, and Mo in these digests were analyzed by Inductively Coupled Plasma Mass Spectrometry (ICP-MS) using a Thermo Scientific X-Series II instrument located in the Keck Collaboratory at Oregon State University. No column chemistry was carried out prior to ICP-MS analysis. Instead, a collision cell was utilized to reduce the formation of oxides that interfere with the analysis of Ag-109 (Nb oxides and Zr oxides and oxyhydroxides) and Cd-114 (Sn oxides). However, it was still necessary to measure the oxide formation, which was typically &lt;5 %, and apply a small oxide correction to the data. The same digests were used to analyze the major and minor element concentrations by ICP-OES (Prodigy, Teledyne Instruments) in the Keck Collaboratory. Metal concentrations were calculated using an external standard calibration curve.</p>
<p>Precision and accuracy were determined using the National Research Council of Canada sediment standards MESS-3 and PACS-2, which were put through the same digestion and analytical procedures as the samples. In general, precision was better than 8% and accuracy was within error for all metals except Al (see the "Table 1" <a href="https://datadocs.bco-dmo.org/docs/305/Ag_Flux_and_Export_Productivity/data_docs/865386/Table1.pdf" target="_blank">Supplemental File</a> (PDF)). The Al values for both sediment standards are slightly (~4 to 5 %) lower than their certified values.</p>
<p>The non-lithogenic (i.e., excess) concentrations of the metals were estimated using Eq. (1), where xsM is the excess concentration of the metal, M<sub>smpl</sub> is the metal concentration in the sample, Al<sub>smpl</sub> is the aluminum concentration in the sample, and (M/Al)<sub>lith</sub> is the metal/Al ratio in lithogenic material.</p>
<p>[xsM] = [M<sub>smpl</sub>] – [Al<sub>smpl</sub>] * (M/Al)<sub>lith</sub></p>
<p>This method of calculating excess concentrations relies on measuring or assuming a reasonable lithogenic value for each metal. In this study, the average shale values reported in Brumsack (2006) were used (i.e., 8.83 wt% Al; 580 µg/g Ba; 850 µg/g Mn; 0.13 µg/g Cd; 0.07 µg/g Ag; 1 µg/g Mo). In addition, because variations in trace metal concentrations can be driven by changes in the concentrations of major components (e.g., dilution by lithogenic material in late fall and winter) all metal data have been converted from concentrations to fluxes using the total particulate flux data provided by Dr. Collier.</p>
<p><strong>Known problems/issues</strong><br />
(1) Year 1 data for the 500 m sediment traps at both sites (i.e., Nearshore samples MT31584 to MT31586 and Gyre samples MT31607 to MT31612) are problematic because evidence (e.g., lower total mass fluxes compared to the 1000 m trap) suggest these shallow traps under-collected settling particulate material.</p>
<p>(2) The 1500 m trap at the Nearshore site in Year 1 (samples MT31396 to MT31401) should have had samples for 13 cups; however, only 6 samples were collected. It is unclear whether the trap failed after cup 6, meaning this cup was open for 237 days, or the trap was programmed improperly and thus each cup was actually open for twice as long. Flux data suggest the latter.</p>
<p>(3) At times fluxes were low and not enough sample was available for an analysis. This was most common at the Gyre site.</p>
<p>(4) The midway (MS) sediment trap samples were not analyzed as a part of this study. Also, there was no Gyre sediment trap samples collected in Year 3.</p>
Specified by the Principal Investigator(s)
<p><strong>Data Notes:</strong></p>
<p>C = cup (e.g., cup 1 is C1)</p>
<p>NS-1 to 3 = Nearshore sediment trap mooring site, years 1 to 3 (see below*)<br />
Gyre-1 to 2 = Gyre sediment trap mooring site, years 1 to 2 (see below*)</p>
<p>MTT samples (column 1) = a bulk sample collected from a failed trap<br />
nd = not determined<br />
na = not applicable / available</p>
<p>* A year refers to the time from when a trap mooring is deployed to when it is recovered and the samples are collected. It does not refer to a calendar year. Traps are named based on the "year" of the project they were recovered.</p>
<p>&nbsp;</p>
Specified by the Principal Investigator(s)
- converted dates for YYYY-MM-DD format;
- renamed fields to conform with BCO-DMO naming conventions.
Specified by BCO-DMO Data Managers
asNeeded
7.x-1.1
Biological and Chemical Oceanography Data Management Office (BCO-DMO)
Unavailable
508-289-2009
WHOI MS#36
Woods Hole
MA
02543
USA
info@bco-dmo.org
http://www.bco-dmo.org
Monday - Friday 8:00am - 5:00pm
For questions regarding this resource, please contact BCO-DMO via the email address provided.
pointOfContact
Thermo Scientific X-Series II Inductively Coupled Plasma Mass Spectrometer
Thermo Scientific X-Series II Inductively Coupled Plasma Mass Spectrometer
PI Supplied Instrument Name: Thermo Scientific X-Series II Inductively Coupled Plasma Mass Spectrometer PI Supplied Instrument Description:Inductively Coupled Plasma Mass Spectrometry (ICP-MS) using a Thermo Scientific X-Series II instrument located in the Keck Collaboratory at Oregon State University Instrument Name: Inductively Coupled Plasma Mass Spectrometer Instrument Short Name:ICP Mass Spec Instrument Description: An ICP Mass Spec is an instrument that passes nebulized samples into an inductively-coupled gas plasma (8-10000 K) where they are atomized and ionized. Ions of specific mass-to-charge ratios are quantified in a quadrupole mass spectrometer. Community Standard Description: http://vocab.nerc.ac.uk/collection/L05/current/LAB15/
Teledyne Instruments, Prodigy Inductively Coupled Plasma - Optical Emission Spectrometer
Teledyne Instruments, Prodigy Inductively Coupled Plasma - Optical Emission Spectrometer
PI Supplied Instrument Name: Teledyne Instruments, Prodigy Inductively Coupled Plasma - Optical Emission Spectrometer Instrument Name: Inductively Coupled Plasma Optical Emission Spectrometer Instrument Short Name:ICP-OES or ICP-AES Instrument Description: Also referred to as an Inductively coupled plasma atomic emission spectroscope (ICP-AES). These instruments pass nebulised samples into an inductively-coupled gas plasma (8-10000 K) where they are atomised and excited. The de-excitation optical emissions at characteristic wavelengths are spectroscopically analysed. It is often used in the detection of trace metals.
bottom-moored sediment traps
bottom-moored sediment traps
PI Supplied Instrument Name: bottom-moored sediment traps Instrument Name: Sediment Trap Instrument Short Name:Sediment Trap Instrument Description: Sediment traps are specially designed containers deployed in the water column for periods of time to collect particles from the water column falling toward the sea floor. In general a sediment trap has a jar at the bottom to collect the sample and a broad funnel-shaped opening at the top with baffles to keep out very large objects and help prevent the funnel from clogging. This designation is used when the specific type of sediment trap was not specified by the contributing investigator. Community Standard Description: http://vocab.nerc.ac.uk/collection/L05/current/33/