# Lake Baringo, Kenya 3.3-2.6 Ma Leaf Wax Isotope Data #----------------------------------------------------------------------- # World Data Service for Paleoclimatology, Boulder # and # NOAA Paleoclimatology Program # National Centers for Environmental Information (NCEI) #----------------------------------------------------------------------- # Template Version 3.0 # Encoding: UTF-8 # NOTE: Please cite Publication, and Online_Resource and date accessed when using these data. # If there is no publication information, please cite Investigators, Title, and Online_Resource and date accessed. # # Online_Resource: https://www.ncdc.noaa.gov/paleo/study/28870 # Description: NOAA Landing Page # Online_Resource: https://www1.ncdc.noaa.gov/pub/data/paleo/paleolimnology/eastafrica/baringo2020wax.txt # Description: NOAA location of the template # # Original_Source_URL: # Description: # # Description/Documentation lines begin with # # Data lines have no # # # Archive: Paleolimnology # # Dataset DOI: # # Parameter_Keywords: geochemistry, carbon isotopes #--------------------------------------- # Contribution_Date # Date: 2020-01-22 #--------------------------------------- # File_Last_Modified_Date # Date: 2020-12-02 #--------------------------------------- # Title # Study_Name: Lake Baringo, Kenya 3.3-2.6 Ma Leaf Wax Isotope Data #--------------------------------------- # Investigators # Investigators: Lupien, R.L.; Russell, J.M.; Yost, C.L.; Kingston, J.D.; Deino, A.L.; Logan, J.; Schuh, A.; Cohen, A.S. #--------------------------------------- # Description_Notes_and_Keywords # Description: Carbon and hydrogen isotopes from plant waxes, and carbon and nitrogen isotopes from bulk organic material, from paleolake Baringo in the southern Kenya Rift, covering ~3.3-2.6 Ma. # A high-resolution, multi-proxy record of Pliocene hominin environments in the Kenya Rift Valley: Analysis of the Baringo-Tugen Hills-Barsemoi (BTB) Drill Core. # Provided Keywords: paleoclimatology, pliocene, organic geochemistry, leaf waxes, carbon isotopes, human evolution, vegetation, precipitation, biomarkers # NOTE: This file updated 2-December-2020 to replace incorrect depth values. In the original version of this data file, a duplicate column of age values # was incorrectly labeled as depth values. Only the Depth column was affected; all other data values in this file are unchanged. #--------------------------------------- # Publication # Authors: Rachel L. Lupien, James M. Russell, Chad L. Yost, John D. Kingston, Alan L. Deino, Jon Logan, Anna Schuh, Andrew S. Cohen # Published_Date_or_Year: 2019-12-25 # Published_Title: Vegetation change in the Baringo Basin, East Africa across the onset of Northern Hemisphere glaciation 3.3-2.6 Ma # Journal_Name: Palaeogeography, Palaeoclimatology, Palaeoecology # Volume: # Edition: 109426 # Issue: # Pages: # Report Number: # DOI: 10.1016/j.palaeo.2019.109426 # Online_Resource: https://www.sciencedirect.com/science/article/abs/pii/S0031018219300707 # Full_Citation: # Abstract: Vegetation in East Africa is generally thought to have shifted from forests to more open grasslands and savannas as global climate cooled and high-latitude ice sheets expanded during the Plio-Pleistocene. Such a shift would have greatly influenced landscape resources, and potentially hominin evolution as well. Existing records of African vegetation spanning these time-scales are generally derived from offshore marine records that record continental-scale changes, or paleosol carbonate records that record very local vegetation changes during the short time intervals of soil carbonate formation. Here we present a new record of basin-scale vegetation change from the late Pliocene (~3.3-2.6 Ma) derived from a drill core from the Chemeron Formation, located in the Baringo Basin/Tugen Hills region of the Kenya Rift Valley. Specifically, we present a new record of the relative abundance of C4 grasses and C3 vegetation based on the carbon isotopic composition of leaf wax biomarkers (d13Cwax), which captures a signal of regional vegetation change. These data demonstrate that vegetation in the Baringo Basin varied greatly between C3 forests and C4 grasslands, and that vegetation exhibits both long-term (secular) trends and orbital-scale variations. The contribution of C3 plants was lower than estimates based on low-resolution carbon isotope data from paleosol carbonates and organic matter in the basin. C3 plants averaged ~53% of the vegetation during the late Pliocene, from ~3.3 to ~3.04 Ma, after which time d13Cwax indicates more open vegetation and ~41% C3 plants. This transition may have been driven by changes in basin geomorphology, but also possibly occurred as part of larger-scale drying and expansion of C4 vegetation in East Africa. In addition to this secular change, we observe high amplitude variability in the d13Cwax record including oscillations between ~80 and ~0% C3 plants. These vegetation changes are correlated with changes in precipitation inferred from d2Hwax and lake level oscillations inferred from sedimentary facies, implying that high-amplitude, orbital-scale variations in precipitation drove significant changes in vegetation resources during the late Pliocene in the Baringo Basin. These variations have important implications for changes in terrestrial resources in light of the evolutionary innovations in the hominin fossil record related to changes in foraging strategies. #--------------------------------------- # Funding_Agency # Funding_Agency_Name: US National Science Foundation # Grant: EAR 1322017, EAR 1338553, BCS 1241790 #--------------------------------------- # Funding_Agency # Funding_Agency_Name: International Continental Drilling Program # Grant: #--------------------------------------- # Site Information # Site_Name: Baringo-Tugen Hills-Barsemoi # Location: Africa>Eastern Africa>Kenya # Country: Kenya # Northernmost_Latitude: 0.55472 # Southernmost_Latitude: 0.55472 # Easternmost_Longitude: 35.9375 # Westernmost_Longitude: 35.9375 # Elevation: #--------------------------------------- # Data_Collection # Collection_Name: Baringo2020wax # First_Year: 3283429 # Last_Year: 2587253 # Time_Unit: cal yr BP # Core_Length: 228 # Notes: core HSPDP-BTB13-1A #--------------------------------------- # Chronology_Information # Chronology: #--------------------------------------- # Variables # Data variables follow that are preceded by "##" in columns one and two. # Variables list, one per line, shortname-tab-longname components (9 components: what, material, error, units, seasonality, archive, detail, method, C or N for Character or Numeric data) # ## depth_m_wax depth,,,m,,paleolimnology,,,N, ## age_Ma_wax age,,,Ma,,paleolimnology,,,N, ## d13Cwax delta 13C,C28 n-alkanoic acid,,per mil,,paleolimnology,,gas chromatograph isotope ratio mass spectrometry,N, ## dDwax delta 2H,C28 n-alkanoic acid,,per mil,,paleolimnology,,gas chromatograph isotope ratio mass spectrometry,N, ## %C3 C3 plants,,,percent,,climate reconstructions,,derived from a linear mixing model of the d13Cwax,N, ## ACL average chain length C24-C32,,,,,paleolimnology,,derived following methods in Castaņeda et al., 2011,N, ## CPI carbon preference index C24-C32,,,,,paleolimnology,,derived following methods in Bray and Evans, 1961,N, # #------------------------ # Data # Data lines follow (have no #) # Data line format - tab-delimited text, variable short name as header # Missing Value: NA depth_m_wax age_Ma_wax d13Cwax dDwax %C3 ACL CPI 10.24 2.587253 -30.38 NA 81.88 27.03 4.27 13.59 2.596119 -28.41 NA 67.69 26.74 4.71 14.27 2.598292 -25.06 NA 43.59 26.41 3.65 16.22 2.600668 -15.6 -68.494 0 27.5 3.34 16.95 2.600848 -27.98 -114.248 64.62 26.76 4.28 18.99 2.603378 -24.01 NA 36.04 26.28 2.67 19.49 2.604322 -24.82 NA 41.85 26.11 2.71 20.04 2.6055 -24.85 NA 42.1 26.23 2.89 21.89 2.609422 -25.52 NA 46.88 26.45 3.13 22.64 2.61079 -29.56 -144.579 75.98 26.57 6.33 23.14 2.612081 -26.13 NA 51.31 26.3 2.57 23.62 2.613412 -24.91 NA 42.52 26.05 2.78 24.32 2.615491 -23.41 -102.073 31.73 27.43 1.94 25.68 2.619213 -27.07 NA 58.02 26.25 4.32 27.33 2.622948 -27.58 NA 61.75 26.74 4.84 28.25 2.625102 -27.56 NA 61.57 26.51 4.77 29.05 2.626874 -25 NA 43.15 26.18 3.87 29.99 2.628914 -26.83 NA 56.35 26.38 3.56 31.20 2.631737 -25.93 NA 49.89 26.52 3.96 32.05 2.633546 -25.77 NA 48.72 26.86 3.21 32.67 2.634842 -27.07 NA 58.05 26.41 3.79 33.46 2.636645 -16.13 -67.884 0 28.2 3.29 34.30 2.638559 -15.35 -68.609 0 27.58 2.43 34.85 2.639868 -24.2 NA 37.4 27.1 3.51 42.24 2.657652 -22.26 -114.711 23.42 26.8 2.36 46.80 2.668017 -20.61 NA 11.58 28.44 1.79 51.97 2.678507 -25.93 -87.75792727 49.89 27.62 4.57 57.05 2.686672 -21.78 NA 19.98 28.54 4.59 62.44 2.697508 -27.05 NA 57.93 26.7 3.54 69.48 2.713399 -27.32 -106.5743576 59.84 28.6 6.04 76.58 2.73 -26.81 NA 56.21 26.06 3.75 78.69 2.742013 -22.1 -161.6690848 22.33 28.94 2.35 81.33 2.761998 -19.97 NA 6.98 27.29 3.27 84.24 2.782736 -24.94 NA 42.73 29.51 2.49 86.59 2.798852 -22.53 NA 25.41 28.32 2.62 89.83 2.817798 -26.71 NA 55.47 29.1 2.58 92.72 2.841613 -25.98 NA 50.22 27.06 3.09 103.20 2.926352 -27.79 NA 63.27 26.53 3.82 110.37 2.962174 -20.04 -107.4216848 7.48 27.56 8.59 117.02 2.992514 -20.76 -136.3844945 12.64 28.63 3.86 123.51 3.020453 -26.82 NA 56.26 27.16 4.35 127.30 3.031734 -24.36 -80.48701212 38.53 27.95 3.67 128.05 3.033584 -20.51 -125.5036945 10.87 28.93 3.59 128.64 3.034882 -20.04 NA 7.46 28.52 3.99 129.34 3.036623 -20.61 NA 11.58 28.57 4.01 130.00 3.038372 -26.33 -124.07584 52.7 28.9 3.14 131.69 3.043021 -20.77 -133.4019939 12.7 29.07 3.07 131.83 3.043412 -22.23 -116.6906121 23.26 28.65 2.63 132.16 3.044282 -25.75 NA 48.58 28.51 3.24 132.72 3.045823 -25.43 NA 46.25 28.98 2.58 133.52 3.04816 -26.3 NA 52.53 27.11 3.56 143.78 3.079633 -27.77 NA 63.1 26.57 3.3 153.95 3.106374 -27.51 NA 61.25 26.74 3.68 159.13 3.111907 -25.01 -150.8792218 43.22 28.88 1.91 164.09 3.122833 -26.69 NA 55.31 26.43 4.47 168.38 3.135176 -30.57 NA 83.21 28.23 3.78 174.28 3.15399 -27.23 NA 59.19 27.52 2.82 178.19 3.166136 -27.52 NA 61.29 28.29 2.66 184.59 3.182575 -22.64 NA 26.19 28.31 1.89 189.69 3.193306 -23.95 -134.1362036 35.58 28.45 5.03 194.83 3.207 -24.69 -141.644 40.93 26.89 2.56 205.05 3.222473 -25.81 -141.953 49.01 27.02 2.71 215.17 3.251303 -25.41 -104.7568485 46.09 27.59 11.39 220.94 3.268189 -24.9 NA 42.41 29.07 2.48 226.13 3.283429 -26.98 NA 57.4 26.17 4.81