{"dp_type": "Dataset", "free_text": "Marine Sediments"}
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24 record(s) found
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Dataset Title/Abstract/Map | NSF Award(s) | Date Created | PIs / Scientists | Project Links | Abstract | Geometry |
---|---|---|---|---|---|---|
Argon thermochronological data on detrital mineral grains from the Weddell Sea embayment
|
1724670 |
2020-10-05 | Williams, Trevor |
Collaborative Research: Deglacial Ice Dynamics in the Weddell Sea Embayment using Sediment Provenance |
This dataset contains 40Ar/39Ar measurements on detrital mineral grains from subglacial till and proximal glacimarine sediment from nine sediment cores along the front of the Filchner and Ronne Ice Shelves. | ["POLYGON((-65 -74,-61 -74,-57 -74,-53 -74,-49 -74,-45 -74,-41 -74,-37 -74,-33 -74,-29 -74,-25 -74,-25 -74.6,-25 -75.2,-25 -75.8,-25 -76.4,-25 -77,-25 -77.6,-25 -78.2,-25 -78.8,-25 -79.4,-25 -80,-29 -80,-33 -80,-37 -80,-41 -80,-45 -80,-49 -80,-53 -80,-57 -80,-61 -80,-65 -80,-65 -79.4,-65 -78.8,-65 -78.2,-65 -77.6,-65 -77,-65 -76.4,-65 -75.8,-65 -75.2,-65 -74.6,-65 -74))"] |
Argon thermochronological data on detrital mineral grains from the Weddell Sea embayment
|
1724670 |
2020-10-05 | Williams, Trevor |
Collaborative Research: Deglacial Ice Dynamics in the Weddell Sea Embayment using Sediment Provenance |
This dataset contains 40Ar/39Ar measurements on detrital mineral grains from till in modern moraines at the edges of the Institute, Foundation, Academy, Recovery, and the Slessor glaciers / ice streams. | ["POLYGON((-70 -80,-65 -80,-60 -80,-55 -80,-50 -80,-45 -80,-40 -80,-35 -80,-30 -80,-25 -80,-20 -80,-20 -80.6,-20 -81.2,-20 -81.8,-20 -82.4,-20 -83,-20 -83.6,-20 -84.2,-20 -84.8,-20 -85.4,-20 -86,-25 -86,-30 -86,-35 -86,-40 -86,-45 -86,-50 -86,-55 -86,-60 -86,-65 -86,-70 -86,-70 -85.4,-70 -84.8,-70 -84.2,-70 -83.6,-70 -83,-70 -82.4,-70 -81.8,-70 -81.2,-70 -80.6,-70 -80))"] |
Radioisotope data (C-14 and Pb-210) from bulk sediments, Larsen A Ice Shelf
|
1341669 0732711 |
2020-06-19 | Taylor, Richard; DeMaster, Dave |
Collaborative Research in IPY: Abrupt Environmental Change in the Larsen Ice Shelf System, a Multidisciplinary Approach -- Cryosphere and Oceans Using Radiochemical Data from Collapsed Ice Shelf Sediments to Understand the Nature and Timing of the Benthic Response to High-Latitude Climate Change |
This file contains Pb-210 data from bulk sediments beneath the collapsed Larsen A Ice Shelf and C-14 data from the organic fraction of the same samples. | ["POLYGON((-61 -64,-60.5 -64,-60 -64,-59.5 -64,-59 -64,-58.5 -64,-58 -64,-57.5 -64,-57 -64,-56.5 -64,-56 -64,-56 -64.1,-56 -64.2,-56 -64.3,-56 -64.4,-56 -64.5,-56 -64.6,-56 -64.7,-56 -64.8,-56 -64.9,-56 -65,-56.5 -65,-57 -65,-57.5 -65,-58 -65,-58.5 -65,-59 -65,-59.5 -65,-60 -65,-60.5 -65,-61 -65,-61 -64.9,-61 -64.8,-61 -64.7,-61 -64.6,-61 -64.5,-61 -64.4,-61 -64.3,-61 -64.2,-61 -64.1,-61 -64))"] |
Labile Organic Carbon distributions on the West Antarctic Peninsula Shelf
|
1341669 0636773 |
2020-05-11 | DeMaster, Dave; Taylor, Richard; Smith, Craig; Isla, Enrique; Thomas, Carrie |
Using Radiochemical Data from Collapsed Ice Shelf Sediments to Understand the Nature and Timing of the Benthic Response to High-Latitude Climate Change Collaborative Research: Benthic Faunal Feeding Dynamics on the Antarctic Shelf and the Effects of Global Climate Change on Bentho-Pelagic Coupling |
This data set is used to describe a new technique for assessing labile organic carbon (LOC) abundances and mean residence times in marine sediments. Radiocarbon is used to determine abundances of labile organic carbon and then a diagenetic organic carbon model, coupled with sediment biotrubation coefficients, is used to assess LOC mean residence times. | ["POLYGON((-71 -64,-70.4 -64,-69.8 -64,-69.2 -64,-68.6 -64,-68 -64,-67.4 -64,-66.8 -64,-66.2 -64,-65.6 -64,-65 -64,-65 -64.7,-65 -65.4,-65 -66.1,-65 -66.8,-65 -67.5,-65 -68.2,-65 -68.9,-65 -69.6,-65 -70.3,-65 -71,-65.6 -71,-66.2 -71,-66.8 -71,-67.4 -71,-68 -71,-68.6 -71,-69.2 -71,-69.8 -71,-70.4 -71,-71 -71,-71 -70.3,-71 -69.6,-71 -68.9,-71 -68.2,-71 -67.5,-71 -66.8,-71 -66.1,-71 -65.4,-71 -64.7,-71 -64))"] |
Sediment macrofaunal abundance and family richness from inner Andvord Bay to the open continental shelf
|
1443680 |
2019-12-31 | Smith, Craig |
Collaborative Research: Fjord Ecosystem Structure and Function on the West Antarctic Peninsula - Hotspots of Productivity and Biodiversity? (FjordEco) |
Sediment macrofaunal data collected by megacore (10-cm diameter sample tubes) along a down-fjord transect from inner Andvord Bay out onto the open continental shelf on the West Antarctic Peninsula. Sediment core samples from 0 - 10 cm depths were fixed in 4% formaldehyde, sieved on a 300 micron seive, and sorted with a dissecting microscope. | ["POLYGON((-66 -64,-65.6 -64,-65.2 -64,-64.8 -64,-64.4 -64,-64 -64,-63.6 -64,-63.2 -64,-62.8 -64,-62.4 -64,-62 -64,-62 -64.1,-62 -64.2,-62 -64.3,-62 -64.4,-62 -64.5,-62 -64.6,-62 -64.7,-62 -64.8,-62 -64.9,-62 -65,-62.4 -65,-62.8 -65,-63.2 -65,-63.6 -65,-64 -65,-64.4 -65,-64.8 -65,-65.2 -65,-65.6 -65,-66 -65,-66 -64.9,-66 -64.8,-66 -64.7,-66 -64.6,-66 -64.5,-66 -64.4,-66 -64.3,-66 -64.2,-66 -64.1,-66 -64))"] |
Easten Antarctic Peninsula Surface Sediment Diatom Data
|
9714371 0732625 |
2019-09-16 | Leventer, Amy |
Collaborative Research in IPY: Abrupt Environmental Change in the Larsen Ice Shelf System, a Multidisciplinary Approach -- Cryosphere and Oceans |
Diatom data from eastern side of Antarctic Peninsula: This file includes quantitative diatom data for surface samples collected on numerous cruises to the eastern side of the Antarctic Peninsula, including NBP0003, NBP0107, LMG0502, NBP0603, and NBP1203. Samples were collected using a variety of tools including Smith-McIntyre Grab, Kasten Core and Jumbo Kasten Core. These data were generated by Amy Leventer (aleventer@colgate.edu) and undergraduate students at Colgate University. All questions regarding the specifics of these data should be directed to Amy Leventer. Quantitative diatom slides were prepared according to the settling technique of Scherer (1995). Cover slips were adhered to the slides using Norland Optical Adhesive #61. Slides were observed under Olympus CX31, BX50 and BX60, and Zeiss Primo Star light microscopes, using a 100X oil immersion objective for a total magnification of 1000X. A minimum of 400 valves or 10 transects was counted for each slide, depending on the absolute diatom abundance. Valves were only counted if >50% complete. Diatoms were identified to species level when possible (Crosta et al., 2005; Armand et al., 2005; Cefarelli et al., 2010). Armand, L.K., X. Crosta, O. Romero, J. J. Pichon (2005), The biogeography of major diatom taxa in Southern Ocean sediments: 1. Sea ice related species, Paleogeography, Paleoclimatology, Paleoecology, 223, 93-126. Cefarelli, A.O., M. E. Ferrario, G. O. Almandoz, A. G. Atencio, R. Akselman, M. Vernet (2010), Diversity of the diatom genus Fragilariopsis in the Argentine Sea and Antarctic waters: morphology, distribution and abundance, Polar Biology, 33(2), 1463-1484. Crosta, X., O. Romero, L. K. Armand, J. Pichon (2005), The biogeography of major diatom taxa in Southern Ocean sediments: 2. Open ocean related species, Palaeogeography, Palaeoclimatology, Palaeoecology, 223, 66-92. Scherer, R. P., A new method for the determination of absolute abundance of diatoms and other silt-sized sedimentary particles, J. Paleolimnol., 12, 171–178, 1995. | ["POLYGON((-64 -63,-63.1 -63,-62.2 -63,-61.3 -63,-60.4 -63,-59.5 -63,-58.6 -63,-57.7 -63,-56.8 -63,-55.9 -63,-55 -63,-55 -63.4,-55 -63.8,-55 -64.2,-55 -64.6,-55 -65,-55 -65.4,-55 -65.8,-55 -66.2,-55 -66.6,-55 -67,-55.9 -67,-56.8 -67,-57.7 -67,-58.6 -67,-59.5 -67,-60.4 -67,-61.3 -67,-62.2 -67,-63.1 -67,-64 -67,-64 -66.6,-64 -66.2,-64 -65.8,-64 -65.4,-64 -65,-64 -64.6,-64 -64.2,-64 -63.8,-64 -63.4,-64 -63))"] |
NBP1502 YoYo camera benthic images from Ross Sea
|
1246357 |
2019-06-03 | Bart, Philip |
Timing and Duration of the LGM and Post-LGM Grounding Events in Whales Deep Paleo Ice Stream, Eastern Ross Sea Middle Continental Shelf |
Still and video benthic images collected during expedition NBP1502 in the Ross Sea using a YoYo camera system. | ["POLYGON((-171 -75.8,-170.5 -75.8,-170 -75.8,-169.5 -75.8,-169 -75.8,-168.5 -75.8,-168 -75.8,-167.5 -75.8,-167 -75.8,-166.5 -75.8,-166 -75.8,-166 -75.99,-166 -76.18,-166 -76.37,-166 -76.56,-166 -76.75,-166 -76.94,-166 -77.13,-166 -77.32,-166 -77.51,-166 -77.7,-166.5 -77.7,-167 -77.7,-167.5 -77.7,-168 -77.7,-168.5 -77.7,-169 -77.7,-169.5 -77.7,-170 -77.7,-170.5 -77.7,-171 -77.7,-171 -77.51,-171 -77.32,-171 -77.13,-171 -76.94,-171 -76.75,-171 -76.56,-171 -76.37,-171 -76.18,-171 -75.99,-171 -75.8))"] |
Palynological samples
|
1048343 |
2019-02-01 | Warny, Sophie |
CAREER: Deciphering Antarctic Climate Variability during the Temperate/Polar Transition and Improving Climate Change Literacy in Louisiana through a Companion Outreach Program |
Thanks to grant # U.S. National Science Foundation ANT-1048343, our group was selected to study about 700 of the recently-acquired sediment samples in Antarctica, covering ~9 regions and geological time frames ranging from the Paleocene to today. The samples were processed for palynological analyses and the slides are curated at the LSU CENEX center. | ["POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))"] |
2016 Paleomagnetic samples from the James Ross Basin, Antarctica
|
1341729 |
2018-04-27 | Skinner, Steven; Kirschvink, Joseph |
Paleomagnetism and Magnetostratigraphy of the James Ross Basin, Antarctica |
["POLYGON((-58.9 -63.5,-58.63 -63.5,-58.36 -63.5,-58.09 -63.5,-57.82 -63.5,-57.55 -63.5,-57.28 -63.5,-57.01 -63.5,-56.74 -63.5,-56.47 -63.5,-56.2 -63.5,-56.2 -63.62,-56.2 -63.74,-56.2 -63.86,-56.2 -63.98,-56.2 -64.1,-56.2 -64.22,-56.2 -64.34,-56.2 -64.46,-56.2 -64.58,-56.2 -64.7,-56.47 -64.7,-56.74 -64.7,-57.01 -64.7,-57.28 -64.7,-57.55 -64.7,-57.82 -64.7,-58.09 -64.7,-58.36 -64.7,-58.63 -64.7,-58.9 -64.7,-58.9 -64.58,-58.9 -64.46,-58.9 -64.34,-58.9 -64.22,-58.9 -64.1,-58.9 -63.98,-58.9 -63.86,-58.9 -63.74,-58.9 -63.62,-58.9 -63.5))"] | |
NBP1502A Cruise Core Data
|
1246353 |
2018-02-05 | Simkins, Lauren; Anderson, John; Prothro, Lindsay |
Evidence for Paleo Ice Stream Collapse in the Western Ross Sea since the Last Glacial Maximum. |
Dataset includes details of cores collected as part of cruise NBP1502A, a list of radiocarbon-dated samples and samples to be radiocarbon-dated, and grain-size data from select NBP1502A cores. | ["POLYGON((-180 -74.37,-178.85 -74.37,-177.7 -74.37,-176.55 -74.37,-175.4 -74.37,-174.25 -74.37,-173.1 -74.37,-171.95 -74.37,-170.8 -74.37,-169.65 -74.37,-168.5 -74.37,-168.5 -74.747,-168.5 -75.124,-168.5 -75.501,-168.5 -75.878,-168.5 -76.255,-168.5 -76.632,-168.5 -77.009,-168.5 -77.386,-168.5 -77.763,-168.5 -78.14,-169.65 -78.14,-170.8 -78.14,-171.95 -78.14,-173.1 -78.14,-174.25 -78.14,-175.4 -78.14,-176.55 -78.14,-177.7 -78.14,-178.85 -78.14,180 -78.14,178.48 -78.14,176.96 -78.14,175.44 -78.14,173.92 -78.14,172.4 -78.14,170.88 -78.14,169.36 -78.14,167.84 -78.14,166.32 -78.14,164.8 -78.14,164.8 -77.763,164.8 -77.386,164.8 -77.009,164.8 -76.632,164.8 -76.255,164.8 -75.878,164.8 -75.501,164.8 -75.124,164.8 -74.747,164.8 -74.37,166.32 -74.37,167.84 -74.37,169.36 -74.37,170.88 -74.37,172.4 -74.37,173.92 -74.37,175.44 -74.37,176.96 -74.37,178.48 -74.37,-180 -74.37))"] |
DeMaster Compiled Larsen Ice Shelf and the West Antarctic Peninsula C14 Data
|
1341669 |
2018-02-03 | DeMaster, Dave |
Using Radiochemical Data from Collapsed Ice Shelf Sediments to Understand the Nature and Timing of the Benthic Response to High-Latitude Climate Change |
This file has C-14 data from the organic matter fraction of Antarctic marine sediments, collected from the collapsed Larsen Ice Shelf and the West Antarctic Peninsula | ["POLYGON((-70 -62,-68.8 -62,-67.6 -62,-66.4 -62,-65.2 -62,-64 -62,-62.8 -62,-61.6 -62,-60.4 -62,-59.2 -62,-58 -62,-58 -62.6,-58 -63.2,-58 -63.8,-58 -64.4,-58 -65,-58 -65.6,-58 -66.2,-58 -66.8,-58 -67.4,-58 -68,-59.2 -68,-60.4 -68,-61.6 -68,-62.8 -68,-64 -68,-65.2 -68,-66.4 -68,-67.6 -68,-68.8 -68,-70 -68,-70 -67.4,-70 -66.8,-70 -66.2,-70 -65.6,-70 -65,-70 -64.4,-70 -63.8,-70 -63.2,-70 -62.6,-70 -62))"] |
LARISSA: Impact of ice-shelf loss on geochemical profiles and microbial community composition in marine sediments of the Larsen A embayment, Antarctic Peninsula
|
0732917 |
2017-12-17 | McCormick, Michael |
Collaborative Research in IPY: Abrupt Environmental Change in the Larsen Ice Shelf System, a Multidisciplinary Approach - Marine Ecosystems. |
Ice-shelf loss along the east coast of the Antarctic Peninsula over recent decades has brought new sources of carbon and energy to the marine benthos likely affecting sediment geochemistry and microbial community composition. To better understand the long-term effects of ice-shelf loss on benthic microbial communities, we conducted a five-station survey along a 160 km transect following the historic path of retreat of the Larsen A ice shelf. All microbial community sequence data is publicly available through the Metagenomics Analysis Server at Argonne National Laboratory (MG-RAST). The project title is "Impact of ice-shelf loss on geochemical profiles and microbial community composition in marine sediments of the Larsen A embayment, Antarctic Peninsula". A key word search using terms from this title at the MG-RAST portal (http://metagenomics.anl.gov/) will return the complete sample list. This submitted dataset summarizes the measured environmental parameters for these same samples (lat., long., water depth, sediment depth, pH, alkalinity, dissolved oxygen, silicate, phosphate, nitrate, nitrite, and ammonium). | ["POLYGON((299.4 -63.1,299.92 -63.1,300.44 -63.1,300.96 -63.1,301.48 -63.1,302 -63.1,302.52 -63.1,303.04 -63.1,303.56 -63.1,304.08 -63.1,304.6 -63.1,304.6 -63.29,304.6 -63.48,304.6 -63.67,304.6 -63.86,304.6 -64.05,304.6 -64.24,304.6 -64.43,304.6 -64.62,304.6 -64.81,304.6 -65,304.08 -65,303.56 -65,303.04 -65,302.52 -65,302 -65,301.48 -65,300.96 -65,300.44 -65,299.92 -65,299.4 -65,299.4 -64.81,299.4 -64.62,299.4 -64.43,299.4 -64.24,299.4 -64.05,299.4 -63.86,299.4 -63.67,299.4 -63.48,299.4 -63.29,299.4 -63.1))"] |
Anvers Trough Foraminifer Stable Isotope data
|
1246378 |
2017-10-25 | Shevenell, Amelia |
Late Quaternary Evolution of the Lambert Glacier/Amery Ice Shelf System, Prydz Bay, Antarctica |
These are unpublished stable isotope data from a series of sediment cores collected during LMG12-11 and LMG13-11 down the axis of Anvers Trough. These records span the LMG to recent. | ["POLYGON((-65.32 -64.15,-65.309 -64.15,-65.298 -64.15,-65.287 -64.15,-65.276 -64.15,-65.265 -64.15,-65.254 -64.15,-65.243 -64.15,-65.232 -64.15,-65.221 -64.15,-65.21 -64.15,-65.21 -64.186,-65.21 -64.222,-65.21 -64.258,-65.21 -64.294,-65.21 -64.33,-65.21 -64.366,-65.21 -64.402,-65.21 -64.438,-65.21 -64.474,-65.21 -64.51,-65.221 -64.51,-65.232 -64.51,-65.243 -64.51,-65.254 -64.51,-65.265 -64.51,-65.276 -64.51,-65.287 -64.51,-65.298 -64.51,-65.309 -64.51,-65.32 -64.51,-65.32 -64.474,-65.32 -64.438,-65.32 -64.402,-65.32 -64.366,-65.32 -64.33,-65.32 -64.294,-65.32 -64.258,-65.32 -64.222,-65.32 -64.186,-65.32 -64.15))"] |
NBP14-02 JPC-54 and JPC-55 Pollen Assemblage data
|
1430550 |
2017-08-18 | Shevenell, Amelia; Smith, Catherine; Domack, Eugene Walter |
Collaborative Research: Totten Glacier System and the Marine Record of Cryosphere - Ocean Dynamics |
Pollen assemblage data for Paleocene to early to middle Eocene sediments collected on Totten continental shelf, East Antarctica. | ["POLYGON((120 -66,120.1 -66,120.2 -66,120.3 -66,120.4 -66,120.5 -66,120.6 -66,120.7 -66,120.8 -66,120.9 -66,121 -66,121 -66.4,121 -66.8,121 -67.2,121 -67.6,121 -68,121 -68.4,121 -68.8,121 -69.2,121 -69.6,121 -70,120.9 -70,120.8 -70,120.7 -70,120.6 -70,120.5 -70,120.4 -70,120.3 -70,120.2 -70,120.1 -70,120 -70,120 -69.6,120 -69.2,120 -68.8,120 -68.4,120 -68,120 -67.6,120 -67.2,120 -66.8,120 -66.4,120 -66))"] |
NBP14-02 JPC-55 Bulk Sediment Carbon and Nitrogen data
|
1430550 |
2017-08-18 | Smith, Catherine; Shevenell, Amelia; Domack, Eugene Walter |
Collaborative Research: Totten Glacier System and the Marine Record of Cryosphere - Ocean Dynamics |
Bulk sediment carbon and nitrogen data data for Paleocene sediments collected on Totten continental shelf, East Antarctica. | ["POLYGON((120 -66,120.1 -66,120.2 -66,120.3 -66,120.4 -66,120.5 -66,120.6 -66,120.7 -66,120.8 -66,120.9 -66,121 -66,121 -66.4,121 -66.8,121 -67.2,121 -67.6,121 -68,121 -68.4,121 -68.8,121 -69.2,121 -69.6,121 -70,120.9 -70,120.8 -70,120.7 -70,120.6 -70,120.5 -70,120.4 -70,120.3 -70,120.2 -70,120.1 -70,120 -70,120 -69.6,120 -69.2,120 -68.8,120 -68.4,120 -68,120 -67.6,120 -67.2,120 -66.8,120 -66.4,120 -66))"] |
History of the East Antarctic Ice Sheet since the mid-Miocene: New Evidence from Provenance of Ice-rafted Debris
|
0944489 |
2014-01-01 | Williams, Trevor; Hemming, Sidney R. |
History of the East Antarctic Ice Sheet since the mid-Miocene: New Evidence from Provenance of Ice-rafted Debris |
Intellectual Merit: The PIs propose to study the stability and dynamics of the East Antarctic ice sheet during the Pliocene in the area of the Wilkes and Aurora subglacial basins. Models indicate the ice sheet is most sensitive to warming in these low-lying areas. This study is important as there is very little direct evidence about which parts of the East Antarctic ice sheet became unstable under warm conditions. In a pilot study the PIs have shown that the isotopic geochemical signature of downcore ice-rafted debris (IRD) can be linked to continental source areas indicating which parts of the ice sheet reached the coast and calved IRD-bearing icebergs. Their initial results suggest rapid iceberg discharge from the Wilkes Land and Adelie Land coastal areas at times in the late Miocene and early Pliocene. In this study the PIs will analyze IRD from IODP sediment cores collected on the continental rise off East Antarctica. By analyzing 40Ar/39Ar ages of hornblende IRD grains, U-Pb ages of zircons, and Sm-Nd isotopes of the fine fraction of several IRD-rich layers for each core, they will be able to fingerprint continental source areas that indicate ice extent and dynamics on East Antarctica. The PIs will also carry out detailed studies across a few of these layers to characterize the anatomy of the ice-rafting event and better understand the mechanism of ice destabilization. Broader impacts: The data collected will be important for scientists in a broad variety of fields. The project will involve one undergraduate student and one summer intern at LDEO, and a graduate student at Imperial College London. The project will expose to cutting edge methodologies as well as an international research team. Data from the project will be deposited in the online databases (SedDB) and all results and methods will be made available to the scientific community through publications in peer-reviewed journals and attendance at international conferences | ["POLYGON((-55 -58,-33.2 -58,-11.4 -58,10.4 -58,32.2 -58,54 -58,75.8 -58,97.6 -58,119.4 -58,141.2 -58,163 -58,163 -60,163 -62,163 -64,163 -66,163 -68,163 -70,163 -72,163 -74,163 -76,163 -78,141.2 -78,119.4 -78,97.6 -78,75.8 -78,54 -78,32.2 -78,10.4 -78,-11.4 -78,-33.2 -78,-55 -78,-55 -76,-55 -74,-55 -72,-55 -70,-55 -68,-55 -66,-55 -64,-55 -62,-55 -60,-55 -58))"] |
Southern Ocean Diatom Taphonomy and Paleoproductivity: A Laboratory Study of Silica Degradation and Export
|
1043690 |
2014-01-01 | Haji-Sheikh, Michael; Scherer, Reed Paul |
Southern Ocean Diatom Taphonomy and Paleoproductivity: A Laboratory Study of Silica Degradation and Export |
Intellectual Merit: Diatom abundance in sediment cores is typically used as a proxy for paleo primary productivity. This record is complicated by variable preservation, with most loss occurring in the water column via dissolution and zooplankton grazing. This study will investigate preservational biases via a series of controlled experiments to create proxies of original productivity based on morphological changes associated with diatom dissolution and fracture. The PIs will utilize fresh diatoms from culture. Specific objectives include: (1) Linking changes in diatom morphology to availability of dissolved silica and other physical and chemical parameters; (2) Documenting the dissolution process under controlled conditions; (3) Assessment of changes in morphology and diatom surface roughness with increased dissolution; (4) Documenting the physical effects of grazing and fecal pellet formation on diatom fragmentation and dissolution; and (5) Analyzing the impact of diatom dissolution on silica and carbon export. These objectives will be achieved by growing Southern Ocean diatom species in the laboratory under differing physical and chemical conditions; controlled serial dissolution experiments on cultured diatoms; analysis of the dissolution process by imaging frustules under scanning electron microscopy (SEM) and with micro-analysis of surface texture by atomic force microscopy (AFM); making the cultures available to krill and other live zooplankton crustaceans in order to analyze the specific effects of grazing and pelletization on diatom morphology; and comparing experimental results with natural plankton, sediment trap material, and selected Holocene, Pleistocene and Pliocene sediment core material. Broader impacts: This work will contribute to understanding of the use of diatom abundance as an indicator of paleoproductivity. The proposed experiments are multi-disciplinary in nature. Importantly, the project was designed, and the proposal largely written, by a Ph.D. candidate. The research proposed here will lead to peer-reviewed publications and provide a base for future studies over the course of an extremely promising scientific career. The project will also support an undergraduate research student at NIU. The PI is heavily involved in science outreach, including classroom visits, museum events and webinars related to evolution and climate change, and is active with NSF-funded outreach activities linked to the ANDRILL and WISSARD programs. He will continue these efforts with this project. | ["POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))"] |
Erosion History and Sediment Provenance of East Antarctica from Multi-method Detrital Geo- and Thermochronology
|
0838722 |
2012-01-01 | Gehrels, George; Reiners, Peter; Thomson, Stuart |
Collaborative Research: Erosion History and Sediment Provenance of East Antarctica from Multi-method Detrital Geo- and Thermochronology |
Much of the inventory of East Antarctic bedrock geochronology, as well as a record of its erosional history, is preserved in Cenozoic sediments around its margin. This project is to use these sediments to understand their sub-ice provenance and the erosional history of the shield by measuring ages of multiple geo- and thermochronometers on single detrital crystals and on multiple crystals in detrital clasts (U/Pb, fission-track, and (U-Th)/He dating of zircon and apatite, and 40Ar/39Ar dating of hornblende, mica, and feldspar). The combination of multi-chronometer ages in single grains and clasts provides a powerful fingerprint of bedrock sources, allowing us to trace provenance in Eocene fluvial sandstones through Quaternary diamicts around the margin. Multiple thermochronometric (cooling) ages in the same grains and clasts also allows us to interpret the timing and rates of erosion from these bedrock sources. Delineating a distribution of bedrock age units, their sediment transport connections, and their erosional histories over the Cenozoic, will in turn allow us to test tectonic models bearing on: (1) the origin of the Gamburtsev Subglacial Mountains, (2) fluvial and topographic evolution, and (3) the history of glacial growth and erosion. | ["POLYGON((61.9 -67.28,63.218 -67.28,64.536 -67.28,65.854 -67.28,67.172 -67.28,68.49 -67.28,69.808 -67.28,71.126 -67.28,72.444 -67.28,73.762 -67.28,75.08 -67.28,75.08 -67.922,75.08 -68.564,75.08 -69.206,75.08 -69.848,75.08 -70.49,75.08 -71.132,75.08 -71.774,75.08 -72.416,75.08 -73.058,75.08 -73.7,73.762 -73.7,72.444 -73.7,71.126 -73.7,69.808 -73.7,68.49 -73.7,67.172 -73.7,65.854 -73.7,64.536 -73.7,63.218 -73.7,61.9 -73.7,61.9 -73.058,61.9 -72.416,61.9 -71.774,61.9 -71.132,61.9 -70.49,61.9 -69.848,61.9 -69.206,61.9 -68.564,61.9 -67.922,61.9 -67.28))"] |
Erosion History and Sediment Provenance of East Antarctica from Multi-method Detrital Geo- and Thermochronology
|
0838729 |
2011-01-01 | Hemming, Sidney R. |
Collaborative Research: Erosion History and Sediment Provenance of East Antarctica from Multi-method Detrital Geo- and Thermochronology |
Much of the inventory of East Antarctic bedrock geochronology, as well as a record of its erosional history, is preserved in Cenozoic sediments around its margin. This project is to use these sediments to understand their sub-ice provenance and the erosional history of the shield by measuring ages of multiple geo- and thermochronometers on single detrital crystals and on multiple crystals in detrital clasts (U/Pb, fission-track, and (U-Th)/He dating of zircon and apatite, and 40Ar/39Ar dating of hornblende, mica, and feldspar). The combination of multi-chronometer ages in single grains and clasts provides a powerful fingerprint of bedrock sources, allowing us to trace provenance in Eocene fluvial sandstones through Quaternary diamicts around the margin. Multiple thermochronometric (cooling) ages in the same grains and clasts also allows us to interpret the timing and rates of erosion from these bedrock sources. Delineating a distribution of bedrock age units, their sediment transport connections, and their erosional histories over the Cenozoic, will in turn allow us to test tectonic models bearing on: (1) the origin of the Gamburtsev Subglacial Mountains, (2) fluvial and topographic evolution, and (3) the history of glacial growth and erosion. | ["POLYGON((-67.2 -58,-43.98 -58,-20.76 -58,2.46 -58,25.68 -58,48.9 -58,72.12 -58,95.34 -58,118.56 -58,141.78 -58,165 -58,165 -59.2,165 -60.4,165 -61.6,165 -62.8,165 -64,165 -65.2,165 -66.4,165 -67.6,165 -68.8,165 -70,141.78 -70,118.56 -70,95.34 -70,72.12 -70,48.9 -70,25.68 -70,2.46 -70,-20.76 -70,-43.98 -70,-67.2 -70,-67.2 -68.8,-67.2 -67.6,-67.2 -66.4,-67.2 -65.2,-67.2 -64,-67.2 -62.8,-67.2 -61.6,-67.2 -60.4,-67.2 -59.2,-67.2 -58))"] |
R/V Nathaniel B. Palmer NBP0603 - Paleohistory of the Larsen Ice Shelf System
|
0338163 |
2010-01-01 | Domack, Eugene Walter |
Collaborative Research: Paleohistory of the Larsen Ice Shelf System: Phase II |
The NSF-supported research icebreaker Nathaniel B. Palmer operates year-round in support of the U.S. Antarctic Program, carrying out global change studies in biological, chemical, physical, and oceanographic disciplines. This data set consists of underway data from leg NBP0603 on the R/V Nathaniel B. Palmer. This leg started at Punta Arenas, Chile and ended at Punta Arenas, Chile. | ["POLYGON((-70.90391 -52.35262,-68.130917 -52.35262,-65.357924 -52.35262,-62.584931 -52.35262,-59.811938 -52.35262,-57.038945 -52.35262,-54.265952 -52.35262,-51.492959 -52.35262,-48.719966 -52.35262,-45.946973 -52.35262,-43.17398 -52.35262,-43.17398 -53.75776,-43.17398 -55.1629,-43.17398 -56.56804,-43.17398 -57.97318,-43.17398 -59.37832,-43.17398 -60.78346,-43.17398 -62.1886,-43.17398 -63.59374,-43.17398 -64.99888,-43.17398 -66.40402,-45.946973 -66.40402,-48.719966 -66.40402,-51.492959 -66.40402,-54.265952 -66.40402,-57.038945 -66.40402,-59.811938 -66.40402,-62.584931 -66.40402,-65.357924 -66.40402,-68.130917 -66.40402,-70.90391 -66.40402,-70.90391 -64.99888,-70.90391 -63.59374,-70.90391 -62.1886,-70.90391 -60.78346,-70.90391 -59.37832,-70.90391 -57.97318,-70.90391 -56.56804,-70.90391 -55.1629,-70.90391 -53.75776,-70.90391 -52.35262))"] |
Antarctica's Geological History Reflected in Sedimentary Radiogenic Isotopes
|
0538580 |
2010-01-01 | van de Flierdt, Tina; Goldstein, Steven L.; Hemming, Sidney R. |
Antarctica's Geological History Reflected in Sedimentary Radiogenic Isotopes |
This project studies sediment from the ocean floor to understand Antarctica's geologic history. Glacially eroded from the Antarctic continent, these sediments may offer insight into the 99% Antarctica covered by ice. The work's central focus is determining crust formation ages and thermal histories for three key areas of East Antarctica--Prydz Bay, eastern Weddell Sea, and Wilkes Land--through a combination of petrography, bulk sediment geochemistry and radiogenic isotopes, as well as isotope chronology of individual mineral grains. One specific objective is characterizing the composition of the Gamburtsev Mountains through studies of Eocene fluvial sediments from Prydz Bay. In addition to furthering our understanding of the hidden terrains of Antarctica, these terrigenous sediments will also serve as a natural laboratory to evaluate the effects of continental weathering on the Hf/Nd isotope systematics of seawater. An important broader impact of the project is providing exciting research projects for graduate and postdoctoral students using state of the art techniques in geochemistry. | ["POLYGON((60 -60,72 -60,84 -60,96 -60,108 -60,120 -60,132 -60,144 -60,156 -60,168 -60,180 -60,180 -61,180 -62,180 -63,180 -64,180 -65,180 -66,180 -67,180 -68,180 -69,180 -70,168 -70,156 -70,144 -70,132 -70,120 -70,108 -70,96 -70,84 -70,72 -70,60 -70,60 -69,60 -68,60 -67,60 -66,60 -65,60 -64,60 -63,60 -62,60 -61,60 -60))"] |
Triple-dating (Pb-FT-He) of Antarctic Detritus and the Origin of the Gamburtsev Mountains
|
0817163 |
2009-01-01 | Gehrels, George; Reiners, Peter |
Collaborative Research: SGER: Triple-dating (Pb-FT-He) of Antarctic Detritus and the Origin of the Gamburtsev Mountains |
This Small Grant for Exploratory Research investigates the origin and evolution of the Gamburtsev subglacial mountains (GSM). These mountains are considered the nucleation point for Antarctica's largest ice sheets; however, being of indeterminate age, they may postdate ice sheet formation. As well, their formation could reflect tectonic events during the breakup of Gondwana. The project studies GSM-derived detrital zircon and apatite crystals from Prydz Bay obtained by the Ocean Drilling Program. Analytical work includes triple-dating thermochronometry by U/Pb, fission track, and (U/Th)/He methods. The combined technique offers insight into both high and low temperature processes, and is potentially sensitive to both the orogenic events and the subsequent cooling and exhumation due to erosion. In terms of broader impacts, this project supports research for a postdoctoral fellow. | ["POLYGON((72 -66,72.3 -66,72.6 -66,72.9 -66,73.2 -66,73.5 -66,73.8 -66,74.1 -66,74.4 -66,74.7 -66,75 -66,75 -66.3,75 -66.6,75 -66.9,75 -67.2,75 -67.5,75 -67.8,75 -68.1,75 -68.4,75 -68.7,75 -69,74.7 -69,74.4 -69,74.1 -69,73.8 -69,73.5 -69,73.2 -69,72.9 -69,72.6 -69,72.3 -69,72 -69,72 -68.7,72 -68.4,72 -68.1,72 -67.8,72 -67.5,72 -67.2,72 -66.9,72 -66.6,72 -66.3,72 -66))"] |
Laboratory Study of Stick-Slip Behavior and Deformation Mechanics of Subglacial Till
|
0538195 |
2009-01-01 | Marone, Chris; Anandakrishnan, Sridhar |
Laboratory Study of Stick-Slip Behavior and Deformation Mechanics of Subglacial Till |
This award supports a project to conduct laboratory experiments and numerical modeling to determine the constitutive properties of subglacial till under dynamic stressing and to test the hypothesis that granular properties of till are sufficient, when coupled elastically to a large ice stream, to reproduce the field observations of triggered slip and subglacial seismicity. Testing will be carried out in a servo-controlled biaxial shear device under controlled temperature and stress conditions, which will allow both sliding and microstructural processes to be studied in detail. The main focus of the work will be on laboratory measurements. In addition, we will construct continuum models to evaluate whether our results can predict complex ice sheet motions and observed characteristics of subglacial seismicity. In terms of broader impacts, the proposed work will encourage interactions between the rock-mechanics and glaciology communities and will bring together members of different scientific backgrounds and vocabularies, but similar problems and data. The project will train undergraduate and graduate students at Penn State University and the scientists involved plan to give presentations to grade school classes, scout groups, and at community open houses. Results will be presented at professional meetings and will be published in a timely manner. The work will result in a better understanding of glacial motion and the physics of earthquake slip, which is essential for understanding ice sheet dynamics and earthquake hazard. | [] |
Linking Modern Benthic Communities and Taphonomic Processes to the Stratigraphic Record of Antarctic Cores
|
0739496 |
2009-01-01 | Furbish, David; Miller, Molly |
Collaborative Research: Linking Modern Benthic Communities and Taphonomic Processes to the Stratigraphic Record of Antarctic Cores |
This project answers a simple question: why are there so few fossils in sediment cores from Antarctica's continental shelf? Antarctica's benthos are as biologically rich as those of the tropics. Shell-secreting organisms should have left a trail throughout geologic time, but have not. This trail is particularly important because these organisms record regional climate in ways that are critical to interpreting the global climate record. This study uses field experiments and targeted observations of modern benthic systems to examine the biases inflicted by fossil preservation. By examining a spectrum of ice-affected habitats, this project provides paleoenvironmental insights into carbonate preservation, sedimentation rates, and burial processes; and will provide new approaches to reconstructing the Cenozoic history of Antarctica. Broader impacts include graduate and undergraduate research and education, development of undergraduate curricula to link art and science, K12 outreach, public outreach via the web, and societal relevance through improved understanding of records of global climate change. | ["POLYGON((163.41667 -77.33333,163.46667 -77.33333,163.51667 -77.33333,163.56667 -77.33333,163.61667 -77.33333,163.66667 -77.33333,163.71667 -77.33333,163.76667 -77.33333,163.81667 -77.33333,163.86667 -77.33333,163.91667 -77.33333,163.91667 -77.369997,163.91667 -77.406664,163.91667 -77.443331,163.91667 -77.479998,163.91667 -77.516665,163.91667 -77.553332,163.91667 -77.589999,163.91667 -77.626666,163.91667 -77.663333,163.91667 -77.7,163.86667 -77.7,163.81667 -77.7,163.76667 -77.7,163.71667 -77.7,163.66667 -77.7,163.61667 -77.7,163.56667 -77.7,163.51667 -77.7,163.46667 -77.7,163.41667 -77.7,163.41667 -77.663333,163.41667 -77.626666,163.41667 -77.589999,163.41667 -77.553332,163.41667 -77.516665,163.41667 -77.479998,163.41667 -77.443331,163.41667 -77.406664,163.41667 -77.369997,163.41667 -77.33333))"] |