A >200 ka U‐Th Based Chronology From Lacustrine Evaporites, Searles Lake, CA

Well‐dated lacustrine records are essential to establish the timing and drivers of regional hydroclimate change. Searles Basin, California, records the depositional history of a fluctuating saline‐alkaline lake in the terminal basin of the Owens River system draining the eastern Sierra Nevada. Here, we establish a U‐Th chronology for the ∼76‐m‐long SLAPP‐SLRS17 core collected in 2017 based on dating of evaporite minerals. Ninety‐eight dated samples comprising nine different minerals were evaluated based on stratigraphic, mineralogic, textural, chemical, and reproducibility criteria. After the application of these criteria, a total of 37 dated samples remained as constraints for the age model. A lack of dateable minerals between 145 and 110 ka left the age model unconstrained over the penultimate glacial termination (Termination II). We thus established a tie point between plant wax δD values in the core and a nearby speleothem δ18O record at the beginning of the Last Interglacial. We construct a Bayesian age model allowing stratigraphy to inform sedimentation rate inflections. We find that the >210 ka SLAPP‐SRLS17 record contains five major units that correspond with prior work. The new dating is broadly consistent with previous efforts but provides more precise age estimates and enables a detailed evaluation of evaporite depositional history. We also offer a substantial revision of the age of the Bottom Mud‐Mixed Layer contact, shifting it from ∼130 ka to 178 ± 3 ka. The new U‐Th chronology documents the timing of mud and salt layers and lays the foundation for climate reconstructions.

[1]  S. Feakins,et al.  Biomarker and Pollen Evidence for Late Pleistocene Pluvials in the Mojave Desert , 2022, Paleoceanography and Paleoclimatology.

[2]  A. Rozas-Davila,et al.  700,000 years of tropical Andean glaciation , 2022, Nature.

[3]  M. Lofverstrom,et al.  A mechanistic understanding of oxygen isotopic changes in the Western United States at the Last Glacial Maximum , 2021, Quaternary Science Reviews.

[4]  T. Lowenstein,et al.  Criteria for the recognition of clastic halite: The modern Dead Sea shoreline , 2021, Sedimentology.

[5]  T. Lowenstein,et al.  Searles Lake evaporite sequences: Indicators of late Pleistocene/Holocene lake temperatures, brine evolution, and pCO2 , 2021 .

[6]  R. Edwards,et al.  U-Th dating of lake sediments: Lessons from the 700 ka sediment record of Lake Junín, Peru , 2020 .

[7]  E. Scott,et al.  The IntCal20 Northern Hemisphere Radiocarbon Age Calibration Curve (0–55 cal kBP) , 2020, Radiocarbon.

[8]  R. Schumer,et al.  A 50,000-year record of lake-level variations and overflow from Owens Lake, eastern California, USA , 2020 .

[9]  J. Knott,et al.  Radiocarbon and paleomagnetic chronology of the Searles Lake Formation, San Bernardino County, California, USA , 2019 .

[10]  E. Galbraith,et al.  Western U.S. lake expansions during Heinrich stadials linked to Pacific Hadley circulation , 2018, Science Advances.

[11]  R. Edwards,et al.  Moisture availability in the southwest United States over the last three glacial-interglacial cycles , 2018, Science Advances.

[12]  J. Rosenthal,et al.  Paleohydrology of China Lake basin and the context of early human occupation in the northwestern Mojave Desert, USA , 2017 .

[13]  Juan M. Lora,et al.  North Pacific atmospheric rivers and their influence on western North America at the Last Glacial Maximum , 2017 .

[14]  R. Edwards,et al.  Reconciliation of the Devils Hole climate record with orbital forcing , 2016, Science.

[15]  M. Lachniet A Speleothem Record of Great Basin Paleoclimate: The Leviathan Chronology, Nevada , 2016 .

[16]  M. Kirby,et al.  Pollen-based evidence of extreme drought during the last Glacial (32.6–9.0 ka) in coastal southern California , 2015 .

[17]  R. Telford,et al.  All age–depth models are wrong, but are getting better , 2015 .

[18]  F. Ieva,et al.  A new robust statistical model for interpretation of differences in serial test results from an individual , 2015, Clinical chemistry and laboratory medicine.

[19]  D. Ibarra,et al.  Steering of westerly storms over western North America at the Last Glacial Maximum , 2015 .

[20]  M. Reheis,et al.  Pluvial lakes in the Great Basin of the western United States: a view from the outcrop , 2014 .

[21]  G. Stock,et al.  Millennial-scale variations in western Sierra Nevada precipitation during the last glacial cycle MIS 4/3 transition , 2014, Quaternary Research.

[22]  M. Lachniet,et al.  Orbital control of western North America atmospheric circulation and climate over two glacial cycles , 2014, Nature Communications.

[23]  R. Edwards,et al.  Improvements in 230Th dating, 230Th and 234U half-life values, and U–Th isotopic measurements by multi-collector inductively coupled plasma mass spectrometry , 2013 .

[24]  A. Martín Sánchez,et al.  Sample quality index to preselect suitable carbonate samples for alpha spectrometry U/Th dating. , 2013, Applied radiation and isotopes : including data, instrumentation and methods for use in agriculture, industry and medicine.

[25]  J. Munroe,et al.  Temporal correspondence between pluvial lake highstands in the southwestern US and Heinrich Event 1 , 2013 .

[26]  D. McGee Absolute-dated, high-resolution records of water balance changes during the last glacial period and deglaciation from lacustrine cave deposits in the Bonneville Basin, Utah, USA , 2012 .

[27]  T. Dawson,et al.  Molecular Paleohydrology: Interpreting the Hydrogen-Isotopic Composition of Lipid Biomarkers from Photosynthesizing Organisms , 2012 .

[28]  J. Christen,et al.  Flexible paleoclimate age-depth models using an autoregressive gamma process , 2011 .

[29]  S. Feakins,et al.  Controls on the D/H ratios of plant leaf waxes in an arid ecosystem , 2010 .

[30]  George I. Smith Late Cenozoic geology and lacustrine history of Searles Valley, Inyo and San Bernardino Counties, California , 2009 .

[31]  J. Christen,et al.  A New Robust Statistical Model for Radiocarbon Data , 2009 .

[32]  B. McKee,et al.  Temporal variability of uranium concentrations and 234U/238U activity ratios in the Mississippi river and its tributaries , 2007 .

[33]  A. Jayko,et al.  Last glacial maximum and Holocene lake levels of Owens Lake, eastern California, USA , 2006 .

[34]  Ittai Gavrieli,et al.  Water, salt, and energy balances of the Dead Sea , 2005 .

[35]  M. Raymo,et al.  A Pliocene‐Pleistocene stack of 57 globally distributed benthic δ18O records , 2005 .

[36]  I. Matthews,et al.  Climatic Control of Riverine and Seawater Uranium-Isotope Ratios , 2004, Science.

[37]  W. Woolfenden A 180,000-year pollen record from Owens Lake, CA: terrestrial vegetation change on orbital scales , 2003, Quaternary Research.

[38]  J. Riotte,et al.  U-Th-Ra Fractionation During Weathering and River Transport , 2003 .

[39]  N. Bader Pollen analysis of death valley sediments deposited between 166 and 114 ka , 2000 .

[40]  R. S. Thompson,et al.  Biomes of western North America at 18,000, 6000 and 0 14C yr bp reconstructed from pollen and packrat midden data , 2000 .

[41]  J. Smoot,et al.  Calibrating Late Quaternary terrestrial climate signals: radiometrically dated pollen evidence from the southern Sierra Nevada, USA , 1999 .

[42]  T. Ku,et al.  200 k.y. paleoclimate record from Death Valley salt core , 1999 .

[43]  T. Ku,et al.  U-Series Chronology of Lacustrine Deposits in Death Valley, California , 1998, Quaternary Research.

[44]  W. Broecker,et al.  A Reassessment of U-Th and14C Ages for Late-Glacial High-Frequency Hydrological Events at Searles Lake, California , 1998, Quaternary Research.

[45]  F. Phillips,et al.  Interstadial climatic cycles: A link between western North America and Greenland? , 1994 .

[46]  K. Ludwig,et al.  Paleoclimatic Inferences from a 120,000-Yr Calcite Record of Water-Table Fluctuation in Browns Room of Devils Hole, Nevada , 1994, Quaternary Research.

[47]  F. Phillips,et al.  A 36Cl chronology of lacustrine sedimentation in the Pleistocene Owens River system , 1991 .

[48]  R. Dorn,et al.  Chronology of expansion and contraction of four Great Basin lake systems during the past 35,000 years , 1990 .

[49]  T. Lowenstein,et al.  Criteria for the recognition of salt-pan evaporites , 1985 .

[50]  R. Rosenbauer,et al.  Uranium-Series Dating of Sediments from Searles Lake: Differences Between Continental and Marine Climate Records , 1985, Science.

[51]  H. Eugster,et al.  Geochemistry of Great Salt Lake, Utah I: Hydrochemistry since 1850 , 1985 .

[52]  George I. Smith Paleohydrologic Regimes in the Southwestern Great Basin, 0–3.2 my ago, Compared with Other Long Records of “Gobal” Climate , 1984, Quaternary Research.

[53]  H. Gove,et al.  Chlorine-36 Dating of Saline Sediments: Preliminary Results from Searles Lake, California , 1983, Science.

[54]  J. Liddicoat,et al.  Core KM-3, a surface-to-bedrock record of late Cenozoic sedimentation in Searles Valley, California , 1983 .

[55]  N. Opdyke,et al.  Palaeomagnetic polarity in a 930-m core from Searles Valley, California , 1980, Nature.

[56]  M. Stuiver,et al.  Subsurface stratigraphy and geochemistry of late Quaternary evaporites, Searles Lake, California, with a section on radiocarbon ages of stratigraphic units , 1979 .

[57]  W. Broecker,et al.  A Direct Comparison of 14C and 230Th Ages at Searles Lake, California , 1978, Quaternary Research.

[58]  A. H. Jaffey,et al.  Precision Measurement of Half-Lives and Specific Activities of U-235 and U238 , 1971 .