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1. Data report: Site U1448 Pleistocene benthic foraminiferal stable isotopes, Andaman Sea, IODP Expedition 353. 10.14379/iodp.proc.353.203.2022

   Clemens, Steven C. (October 2022, Proceedings of the International Ocean Discovery Program Expedition reports)

   This data report presents the benthic foraminiferal oxygen and carbon isotope records for International Ocean Discovery Program Site U1448 in the Andaman Sea. The record includes 1764 analyses spanning from the core top to 203.19 m core composite depth below the seafloor, Method D. This depth interval spans the past 2.755 My with an average temporal resolution of ~1.9 ky (14 cm sample interval). 

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2. Data report: Site U1448 leaf wax hydrogen isotopes, IODP Expedition 353, Andaman Sea

   https://doi.org/10.14379/iodp.proc.353.204.2025  

   McGrath, SM; Clemens, SC; Huang, Y (October 2025, International Ocean Discovery Program)

   This data report presents the leaf wax hydrogen isotopic record from International Ocean Discovery Program Site U1448 in the Andaman Sea. The record includes 270 analyses spanning from the core top to 39.24 m core composite depth below the seafloor. This depth interval spans the past 638 ky with an average temporal resolution of ~2.37 ky (14 cm sample interval). Site U1448 has a published benthic isotope chronostratigraphy as well as previously published paired leaf wax carbon isotope data, enabling a better understanding of hydroclimate in the Andaman region. 

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3. Can We See Dust from the 1992 Fall of the Peekskill Meteorite in Hudson River Sediments and Can We Use It as a Stratigraphic Marker?(Regional and Local Stratigraphic Markers in Three Hudson River Cores Taken Near Peekskill, New York: LWB4-1)

   Diallo, M. B.; McCann, B.; Abdul, B.; Adeghe, S.; Abbott, D. H.; Bostick, B. C.; Chang, C.; Block, K. A. (December 2018, American Geophysical Union, Fall Meeting 2018, abstract #B53I-2168)

   We have been studying the stratigraphy of core LWB4-1 taken in 2001 in the Hudson River about 100 meters north of the calculated transit path of the Peekskill meteorite in October 1992. We measured magnetic susceptibility at 1cm intervals from 0 -70 cm depth and found a layer with a magnetic susceptibility of 11 cgs units at 6 cm depth. This is the highest susceptibility in the top 40 cm of the core. Scanning X-Ray Fluorescence spectroscopy revealed the high susceptibility layer at 6 cm depth is part of a 3 cm interval with a high Ni/Cr ratio, but the depth of the peak in the Ni/Cr ratio is poorly resolved due to measurement error. We plan to dry and homogenize discreet samples for analysis on bench top XRF to reduce Ni and Cr error. Based on our identification of the base of modern Pb at 68 cm depth, the top 40 cm of the core covers the time interval from 2001 to 1930. From previous work on Central Park Lake, the base of modern Pb represents the year 1880 A.D. A uniform sedimentation rate model is supported a peak in Pb and As at 8 cm depth. The peak might represent the 1988 ban on the use of Pb arsenide and the start of use of DDT as a pesticide. We found a second peak in Pb at 37.5cm potentially from 1938, the date at which incineration was banned in New York City. We found a third peak in Pb at 50.5cm that might be from World War I around 1914. We found two deeper susceptibility peaks of 12 cgs at 43 cm and 8 cgs at 59 cm. These peaks could represent major Hudson River floods in 1927 and 1903. 137Cs and 210Pb 210 dating are in progress and will help us to determine if our age model is correct. Also, our core exhibits a distinct increase in Ca content starting at 18-25 cm depth and increasing towards the top of the core. This increase could be due to increased erosion, anthropogenic inputs or increased dissolution of CaCO3 rich rocks. We are measuring CaCO3 in the core to better determine the origin of this increase of Ca. 

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4. Data report: revised Pleistocene sediment splice for Site U1457, IODP Expedition 355

   https://doi.org/10.14379/iodp.proc.355.202.2019  

   Lyle, M.; Saraswat, R. (February 2019, Proceedings of the International Ocean Discovery Program)

   null (Ed.)

   Sediment cores from adjacent holes at a drill site are typically spliced to make a continuous sediment record that spans sediment gaps that occur between sediment cores within each hole. The splice also provides a template for later sampling. During International Ocean Discovery Program Expedition 355, we made such a splice for both Sites U1456 and U1457 using shipboard Whole-Round Multisensor Logger and Section Half Multisensor Logger data. The shipboard-spliced sediment section at Site U1457 was constructed for the advanced piston corer interval to an age of about 1.5 Ma. Additional postexpedition planktonic foraminifer stable isotope data (Globigerinoides ruber δ18O) show that the shipboard stratigraphic tie between Cores 355-U1457B-1H and 355-U1457A-1H was wrong. This paper describes a revised splice that appends Core 355-U1457A-1H to the base of Core 355-U1457B-1H. The core composite depth below seafloor depths of the remaining splice have been revised because of this change. The revised splice interval is also longer by 1.2 m to accommodate the lower part of Core 355-U1457B-1H. In addition, a break of unknown thickness is present between Cores 355-U1457B-1H and 355-U1457A-1H. The revised splice interval table is included in this report. 

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5. Data report: Site U1523 composite section and stratigraphic splice based on X-ray fluorescence data, IODP Expedition 374

   https://doi.org/10.14379/iodp.proc.374.202.2022  

    Kulhanek, D.K.; Prunella, C.; McLaughlin, J.R.; Griffin, B.; McKay, R.M.; Patterson, M.O.; Gales, J.; Shevenell, A.E.; van Peer, T.E. (September 2022, Proceedings of the International Ocean Discovery Program)

   Contribution of melting Antarctic Ice Sheets (AIS) to rising sea level remains one of the least quantified inputs to predictive models for the future. To improve these estimates, International Ocean Discovery Program Expedition 374 cored five sites in the Ross Sea, Antarctica, to examine the stability of the AIS to past intervals of global warmth. Site U1523 proved difficult to core because of the presence of gravel lags and indurated intervals; thus, we cored three holes with overlapping stratigraphy at that site to recover a more complete stratigraphic section. Given these challenges, no attempt was made to create a composite depth scale or stratigraphic splice during the expedition. Here we use a combination of physical property data (primarily magnetic susceptibility and natural gamma radiation), X-ray fluorescence core scanning, and visual core description to construct a core composite depth below seafloor (CCSF) depth scale to the base of Hole U1523B. This composite depth scale is discontinuous because of challenging coring conditions and variable core recovery, although there are several intervals of reasonably good stratigraphic continuity between 0 and 26 m CCSF and 82 and 96 m CCSF. We also created a stratigraphic splice from 0 to 93.95 m CCSF, although the splice is only continuous to 15.82 m CCSF. Additionally, we mapped the off-splice interval of Core 374-U1523E-1H to the composite depth scale over several intervals with significant core disturbance by stretching and squeezing to obtain a best fit. Development of the composite depth scale and stratigraphic splice will improve postcruise research results by allowing scientists to compare samples from different holes on the same depth scale. 

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