# South Atlantic Coccolith Assemblage and Morphology Data from the Early Oligocene #----------------------------------------------------------------------- # World Data Service for Paleoclimatology, Boulder # and # NOAA Paleoclimatology Program #----------------------------------------------------------------------- # Template Version 4.0 # Encoding: UTF-8 # NOTE: Please cite original publication, NOAA Landing Page URL, dataset and publication DOIs (where available), and date accessed when using downloaded data. # If there is no publication information, please cite investigator, study title, NOAA Landing Page URL, and date accessed. # # Description/Documentation lines begin with '#' followed by a space # Data lines have no '#' # # NOAA_Landing_Page: https://www.ncei.noaa.gov/access/paleo-search/study/37661 # Landing_Page_Description: NOAA Landing Page of this file's parent study, which includes all study metadata. # # Study_Level_JSON_Metadata: https://www.ncei.noaa.gov/pub/data/metadata/published/paleo/json/noaa-ocean-37661.json # Study_Level_JSON_Description: JSON metadata of this data file's parent study, which includes all study metadata. # # Data_Type: Paleoceanography # # Dataset_DOI: 10.25921/v1pb-vb30 # # Science_Keywords: Milankovitch, biogeography #--------------------------------------- # Resource_Links # # Data_Download_Resource: https://www.ncei.noaa.gov/pub/data/paleo/paleocean/atlantic/ma2023/ma2023-dsdp522_morph.txt # Data_Download_Description: NOAA Template File; Coccolith Morphology Data # #--------------------------------------- # Contribution_Date # Date: 2023-02-27 #--------------------------------------- # File_Last_Modified_Date # Date: 2023-04-12 #--------------------------------------- # Title # Study_Name: South Atlantic Coccolith Assemblage and Morphology Data from the Early Oligocene #--------------------------------------- # Investigators # Investigators: Ma, Ruigang; Liu, Chuanlian; Jin, Xiaobo #--------------------------------------- # Description_Notes_and_Keywords # Description: The dataset includes coccolithophores morphology and assemblage from the South Atlantic Ocean, early Oligocene (~32.8-33.1 Ma). The data are derived from 45 marine sediment samples collected at DSDP Site 522, Core 33. The first dataset is the relative abundances (%) of different species/genera of coccolithophores. The second dataset is the morphology record (size, given in µm) that obtained by measuring 100, 30 and 30 specimens of coccolithophore genra Reticulofenestra, Dictyococcites and Coccolithus, repectively. #--------------------------------------- # Publication # Authors: Ma, R.; Jin, X.; Liu C. # Published_Date_or_Year: 2023-04-01 # Published_Title: High-resolution coccolithophores morphologic changes in response to orbital forcings during early Oligocene # Journal_Name: Geochemistry, Geophysics, Geosystems # Volume: 24 # Edition: # Issue: 4 # Pages: # Report_Number: e2022GC010746 # DOI: 10.1029/2022GC010746 # Online_Resource: # Full_Citation: # Abstract: Early Oligocene global climate was characterized by initiated Antarctic glaciation and meridional overturning circulation, which then led to profound eutrophication in the upper ocean. Generating a high-resolution coccolith record help to understand the responses of the marine phytoplankton to the newly established environment. Using highly resolved (~6 kyr time-resolution) marine sediment samples from Deep Sea Drilling Project Site 522 in the South Atlantic Ocean, we conducted a comprehensive morphologic study on coccoliths from the genera Reticulofenestra, Dictyococcites and Coccolithus, that dominated the interval between ~33.1 to 32.8 Ma. Our results showed that the size variations of three measured genera are significantly correlated (p<0.01) to each other, indicating homogeneous responses to the environmental changes. Moreover, spectrum analysis on integrated morphologic data of all measured coccoliths showed distinct obliquity (~40-kyr) and precession (~23-kyr and ~18-kyr) cycles. We suggest that these variations were mainly driven by temperate, short-term ecological fluctuations, which periodically altered the nutrient condition in the common living habitats for the studied coccolithophores. We proposed two tentative explanations focusing on the obliquity signal. First, the cyclic variation could result from obliquity-modulated ice volume changes and variations in ocean circulation intensity, which influenced nutrient export from deep waters to the upper ocean. Alternatively, the changes in coccolith size may indicate the strength of seasonality that influenced the upper ocean mixing on the west coast of South Africa. #--------------------------------------- # Funding_Agency # Funding_Agency_Name: National Natural Science Foundation of China # Grant: 41930536 #--------------------------------------- # Site_Information # Site_Name: DSDP 522 # Location: South Atlantic Ocean # Northernmost_Latitude: -26.114 # Southernmost_Latitude: -26.115 # Easternmost_Longitude: 5.129 # Westernmost_Longitude: 5.128 # Elevation_m: -4441 #--------------------------------------- # Data_Collection # Collection_Name: DSDP522_morph # First_Year: 33101670 # Last_Year: 32823050 # Time_Unit: calendar year before present # Core_Length_m: 148.7 # Parameter_Keywords: other # Notes: #--------------------------------------- # Chronology_Information # Chronology: #--------------------------------------- # Variables # PaST_Thesaurus_Download_Resource: https://www.ncei.noaa.gov/access/paleo-search/skos/past-thesaurus.rdf # PaST_Thesaurus_Download_Description: Paleoenvironmental Standard Terms (PaST) Thesaurus terms, definitions, and relationships in SKOS format. # # Data variables follow that are preceded by "##" in columns one and two. # Variables list, one per line, shortname-tab-var components: what, material, error, units, seasonality, data type, detail, method, C or N for Character or Numeric data) # ## Depth depth,,,meter,,Paleoceanography,,,N, ## Age age,,,million years ago,,Paleoceanography,,,N, ## Reticulo-Mean length,coccolithophore,,micrometer,,Paleoceanography,averaged,,N,coccolith morphometry; measured long axis of specimens; mean of 100 Reticulofenestra specimens ## Reticulo-sd length,coccolithophore,one standard deviation,micrometer,,Paleoceanography,,,N,coccolith morphometry; measured long axis of specimens; standard deviation of 100 Reticulofenestra specimens ## Dictyo-Mean length,coccolithophore,,micrometer,,Paleoceanography,averaged,,N,coccolith morphometry; measured long axis of specimens; mean of 30 Dictyococcites specimens ## Dictyo-sd length,coccolithophore,one standard deviation,micrometer,,Paleoceanography,,,N,coccolith morphometry; measured long axis of specimens; standard deviation of 30 Dictyococcites specimens ## Cocco-Mean length,coccolithophore,,micrometer,,Paleoceanography,averaged,,N,coccolith morphometry; measured long axis of specimens; ; mean of 30 Coccolithus specimens ## Cocco-sd length,coccolithophore,one standard deviation,micrometer,,Paleoceanography,,,N,coccolith morphometry; measured long axis of specimens; standard deviation of 30 Coccolithus specimens ## All-Mean length,coccolithophore,,micrometer,,Paleoceanography,averaged,,N,coccolith morphometry; measured long axis of specimens; mean of 100 randomly picked coccolith specimens ## All-sd length,coccolithophore,one standard deviation,micrometer,,Paleoceanography,,,N,coccolith morphometry; measured long axis of specimens; standard deviation of 100 randomly picked coccolith specimens #------------------------ # Data: # Data lines follow (have no #) # Data line format - tab-delimited text, variable short name as header # Missing_Values: Depth Age Reticulo-Mean Reticulo-sd Dictyo-Mean Dictyo-sd Cocco-Mean Cocco-sd All-Mean All-sd 126.37 32.823 6.1613 0.5734 9.966 0.9205 9.7394 1.627 7.5541 1.7122 126.42 32.828 6.3201 0.5501 9.7583 1.1464 9.179 1.007 7.542 1.6874 126.48 32.835 6.4766 0.5176 10.077 1.3482 9.7442 1.896 7.7591 1.6886 126.53 32.84 6.4151 0.4808 10.128 1.2825 10.322 1.664 7.4385 1.6673 126.57 32.845 6.309 0.613 10.41 0.9906 9.211 1.313 7.4048 1.7281 126.62 32.85 6.2281 0.5362 9.6473 1.154 9.1627 1.275 7.2033 1.5789 126.67 32.855 6.1032 0.5038 9.4337 1.3046 9.4053 1.376 7.2821 1.6502 126.73 32.862 6.8098 0.5321 9.6667 1.5352 10.462 1.507 8.3335 2.3375 126.78 32.867 6.1031 0.4706 9.02 1.32 10.23 1.43 7.9165 2.1814 126.83 32.873 6.4122 0.5321 10.55 1.364 9.687 1.235 7.8287 1.7133 126.92 32.882 6.6737 0.5719 10.679 1.2161 9.9003 1.844 7.6894 2.2074 126.98 32.889 6.798 0.5384 10.728 1.8514 10.633 1.78 7.5451 2.1778 127.03 32.894 6.921 0.5643 10.041 1.6814 9.548 1.449 7.5774 2.4776 127.06 32.897 6.8854 0.4942 10.631 1.8679 10.741 2.723 8.6402 3.0877 127.11 32.903 6.8284 0.4322 10.757 2.2645 10.655 1.611 8.1684 2.6379 127.18 32.91 6.5263 0.5451 9.8063 0.9897 9.877 1.797 7.1655 1.8137 127.23 32.916 6.3539 0.6396 10.056 1.4693 10.102 2.228 7.1617 1.5067 127.29 32.922 6.7796 0.5571 10.53 1.502 10.554 2.652 7.5227 2.0174 127.34 32.928 6.8423 0.6169 10.173 1.3839 10.434 1.339 6.7482 1.277 127.39 32.933 6.1757 0.7224 10.361 1.1989 10.477 2.106 7.9306 2.8648 127.44 32.938 6.6355 0.6138 10.483 1.0744 9.7133 1.19 7.1762 1.6345 127.51 32.946 6.4835 0.5529 9.409 1.0453 9.177 1.273 7.3488 2.1008 127.57 32.952 6.5758 0.487 10.026 1.4104 9.656 1.164 8.2565 2.4871 127.63 32.959 6.0834 0.5311 10.656 1.3465 10.033 1.074 7.437 1.9723 127.75 32.975 6.3054 0.5837 9.8283 1.6393 9.6793 1.284 7.8099 2.3029 127.83 32.985 6.5845 0.5387 10.698 1.2951 10.775 2.062 7.794 2.0715 127.88 32.989 6.2053 0.6403 10.226 1.5332 10.263 1.849 8.0638 2.3624 127.93 32.993 6.4937 0.4996 9.8313 1.2594 9.182 0.995 7.7827 1.8272 128.00 32.999 6.4022 0.4803 10.183 1.3081 10.192 3.086 8.3824 2.2072 128.06 33.005 6.4043 0.5692 10.459 1.1532 10.558 2.089 7.8263 2.5584 128.12 33.012 6.1868 0.5003 10.367 1.3942 9.325 1.357 7.3751 1.6156 128.14 33.014 6.438 0.5395 10.461 1.992 10.428 1.595 7.4165 1.7539 128.20 33.02 7.0043 0.4834 10.887 1.1933 10.618 2.934 8.5185 3.1384 128.27 33.028 6.4055 0.671 9.7837 1.672 10.038 1.652 7.8005 2.372 128.33 33.034 6.5756 0.6045 10.931 1.403 12.066 3.368 8.2792 2.6753 128.40 33.042 6.8037 0.4401 10.828 1.3485 10.263 1.651 7.3679 1.9392 128.47 33.049 6.4138 0.5148 10.976 1.1408 10.002 1.471 7.3679 1.9392 128.60 33.062 6.4159 0.6662 10.239 1.3571 11.239 3.113 7.8264 2.108 128.68 33.068 7.2354 0.6781 10.233 1.4318 10.406 2.34 8.6642 3.0831 128.74 33.074 6.3411 0.7049 10.623 1.5618 10.559 2.037 7.3532 1.8769 128.82 33.08 6.4048 0.7574 10.336 1.1229 10.737 2.248 7.9591 2.5853 128.87 33.085 6.7869 0.953 10.988 1.4812 10.933 3.038 8.2328 2.809 128.95 33.091 6.0931 0.8495 10.534 1.1418 9.468 1.218 7.109 1.5314 129.01 33.097 5.9852 0.8023 9.783 1.1696 9.74 1.365 7.5833 2.0753 129.07 33.102 6.2188 0.6595 10.135 1.2239 10.049 1.711 7.4504 2.1587