A 200 kyr record of lake-level change from the Carrizo Plain, Central Coastal California

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1 A 200 kyr record of lake-level change from the Carrizo Plain, Central Coastal California R. Negrini, T. Miller, R. Stephenson, R. Ramirez, J. Leiran, D. Baron, P. Wigand, CSU Bakersfield D. Rhodes, Georgia Southern University T. Algeo, University of Cincinnati pasadena.wr.usgs.gov/ office/galetzka/imgbank/

Testing climate models with records from closed lakes Soda Lake in the Carrizo Plain Geomorphic setting and previous work Initial results Coring Lithology Magnetic susceptibility SEM petrography

2 Testing climate models with records from closed lakes Soda Lake in the Carrizo Plain Geomorphic setting and previous work Initial results Coring Lithology Magnetic susceptibility SEM petrography Age control XRD of evaporate minerals Work in progress Spectral gamma logs Charcoal and pollen counts Coring South Basin for youngest part of record pasadena.wr.usgs.gov/ office/galetzka/imgbank/

3 Lake-record contributions: Milankovitch Time-Scales ( yr) N after Benson (2004)

Lake-record contributions: Milankovitch Time-Scales (10 4-10 6 yr) 0 SPECMAP OIS

4 Lake-record contributions: Milankovitch Time-Scales ( yr) 0 SPECMAP OIS Inferred depth (arbitrary units) Age (Ka) polar ice volume deeper GSL

5 Lake-record contributions: Milankovitch Time-Scales ( yr) Owens Lake Paleoprecipitation Record polar ice volume Sierran precipitation from Smith et al. (1997)

6 Lake-record contributions: Milankovitch Time-Scales ( yr) W. W. Norton. After Flint, 1971

) -44-42 -40-38 -36 H2 GISP2 Age (Ka) 30 35 40 45 H3

7 Lake-record contributions: Millennial Time-Scales ( yr) GISP2 Ice Core δ 18 O ( o / oo ) H2 GISP2 Age (Ka) H3 H4 H IS # Warmer North Atlantic

8 Lake-record contributions: Millennial Time-Scales ( yr) Post-LCM millennial scale climate features in Owens Lake core (from Benson et al., 1997)

9 Lake-record contributions: Millennial Time-Scales ( yr) GISP2 Ice Core δ 18 O ( o / oo ) B&B Core Inclination ( ) GISP2 Age (Ka) H2 H3 H4 H IS # Wono Ash 6 8 MSH Cy Ash MLE LE high 36 Cl in GISP2 core Warmer North Atlantic Summer Lake B&B Core IRM (A/m) Deeper Summer Lake 50 magnetic excursions in Summer Lake Core

10 Lake-record contributions: Millennial Time-Scales ( yr) Great Basin response to cold temperatures in the North Atlantic North Pacific SSTs decrease in response to lower temperatures in North Atlantic (Mikolajewicz, et al. 1997).

11 Climate Change on Millennial Time-Scales ( yr)

12 Pluvial Lakes of the Western U.S. (after Benson, 2004) N

13 Location of Soda Lake relative to the Santa Barbara Basin OL TL SL SBB BL pasadena.wr.usgs.gov/ office/galetzka/imgbank/

14 Soda Lake in the Carrizo Plain, San Luis Obispo County, CA South Basin North Basin N J. Shelton

15 Geomorphic features relevant to past lake levels N trimmed ridges slickspots South Basin active clay dune (lunette) North Basin

16 Carrizo Plains? N

17 Geomorphic evidence for 17m variation in lake depth

18 Eigenbrode (1999) Coring Site in South Basin SLC-SB

19 Eigenbrode (1999) Core analyses Lithology and geochemistry study of <2 m core representing late Holocene

20 Lake Flat Coring Sites of Present Study SL-1 4 m core auger flight samples to 14 m SLC-SB

21 Lake Flat Coring Sites of Present Study SL-1 4 m core auger flight samples to 14 m NSL-1 SLC-SB 40 m core

22 Recovery data for 40 m NSL-1 Core (recovery ~80%) *Top Cum Depth of **top of core liner bgs (m) Length of liner (m) Dpth below liner top to top of sediment (cm) Dpth above liner bott to bott of sediment (cm) ***Top Cum Depth of top of sediment in core (m) Cum Depth of bottom of sediment in core (m) Total thickness of intact core (m) Core Drive NSL-1A NSL-1A NSL-1A NSL-1A NSL-1B NSL-1B NSL-1B NSL-1B NSL-1B NSL-1B NSL-1B NSL-1B NSL-1B NSL-1B NSL-1B NSL-1B NSL-1B NSL-1B NSL-1B NSL-1B NSL-1B NSL-1B NSL-1B NSL-1B NSL-1B NSL-1B NSL-1B

23 Oxidized Lithology light olive-brown (5Y 6/4) 1-10 mm, euhedral, gypsum xtals common microscopic gypsum xtals in clay matrix relatively high magnetic susceptibility (κ=20-60 cgs units) massive pollen preservation very poor throughout core µm charcoal ubiquitous no diatoms

Reduced Lithology dark gray (5Y 4/1); greenish gray (10Y or 10GY 5/1) 1-10 mm, euhedral, gypsum xtals Uncommon; sometimes in discrete layers microscopic gypsum

24 Reduced Lithology dark gray (5Y 4/1); greenish gray (10Y or 10GY 5/1) 1-10 mm, euhedral, gypsum xtals Uncommon; sometimes in discrete layers microscopic gypsum xtals in clay matrix very low magnetic susceptibility (κ<20 cgs units) massive pollen preservation very poor throughout core µm charcoal ubiquitous no diatoms

25 Reduced/oxidized lithology = deep/shallow lake or vice-versa? Initial hypothesis can be developed using distribution of lithologies throughout core and initial ages. Can do this easily because κ is proxy for lithology. magnetic susceptibility (cgs units) 120 Whole-core magnetic susceptibility log of 40m Soda Lake core x10e-6 depth (m)

26 magnetic susceptibility (cgs units) Reduced/oxidized lithology = deep/shallow lake or vice-versa? Initial hypothesis can be developed using distribution of lithologies throughout core and initial ages. Can do this easily because κ is proxy for lithology. 0 Whole-core magnetic susceptibility log of 40m Soda Lake core x10e two prominent reduced zones depth (m)

27 Magnetic susceptibility contrast across boundary between oxidized and reduced sediments bottom core NSL-1B-8 magnetic susceptibility (cgs units) lower reduced zone depth (m)

28 1-50 µm magnetite easily identified in oxidized sediments; none observed in reduced sediments bottom core NSL-1B-8 Mt Mt Mt Gp Mt

29 Copper minerals occasionally observed in reduced sediments Cu minerals 1 cm gypsum

30 Electron microscopy of Copper minerals gypsum Cu minerals gypsum % 20 0 C O Si S Cl Ca Cu

31 Initial age control of new core x10e-06? SL-1A Core (1m higher elevation due to post-depositional tilting) NSL-1 Core

32 Initial age control of new core x10e-06? cal Kyr on charcoal (17.74 ± C Kyr) SL-1A Core (1m higher elevation due to post-depositional tilting) NSL-1 Core

33 Initial age control of new core x10e-06? cal Kyr on charcoal * SL-1A Core (1m higher elevation due to post-depositional tilting) NSL-1 Core *22.5 cal Kyr on seed pods (19.09 ± C Kyr)

34 Seed pods of Scirpus Maritimus(?) (alkali bulrush) found in 1 cm-thick layer within upper zone of reduced sediments. Ostracodes also common in this layer.

35 Initial age control of new core x10e-06? cal Kyr on charcoal * SL-1A Core (1m higher elevation due to post-depositional tilting) NSL-1 Core *22.5 cal Kyr on seed pods (19.09 ± C Kyr)

36 Preliminary climate model * x10e-06? MIS cal Kyr on charcoal SL-1A Core (1m higher elevation due to post-depositional tilting) MIS 6? NSL-1 Core MIS 5? *22.5 cal Kyr on seed pods (19.09 ± C Kyr)

37 Preliminary climate model * x10e-06? MIS cal Kyr on charcoal millennial-scale lake-level changes? MIS 6? MIS 5? *22.5 cal Kyr on seed pods (19.09 ± C Kyr)

38 Whole core susceptibility values were near sensor sensitivity limit bottom core NSL-1B-8 magnetic susceptibility (cgs units) lower reduced zone (MIS 6?) depth (m)

39 Magnetic susceptibility of box samples discrete sample measurements

40 Refined hypothesis: MIS6(?) lake deepens up until Termination whole core measurements

41 Testing the refined hypothesis: evaporite mineralogy peak criteria = large amplitude, little overlap with other peaks, good regression stats

42 Testing the refined hypothesis discrete sample measurements

44 spectral gamma log data

46 Pollen, etc. found in NSL-1A-3 core drive juniper charcoal artemisia pinus atriplex blue-green algae

47 Late Pleistocene through Holocene record from South Basin N South Basin

48 Late Pleistocene through Holocene record from South Basin N South Basin pasadena.wr.usgs.gov/ office/galetzka/imgbank/

Conclusions Lake-level proxies are consistent and suggestive of both Milankovitch- and millennial-scale responses Dateable material is present Pollen and charcoal are present in high enough

49 Conclusions Lake-level proxies are consistent and suggestive of both Milankovitch- and millennial-scale responses Dateable material is present Pollen and charcoal are present in high enough concentrations to provide more straightforward estimates of paleoclimate Record potentially covers past 200 kyr including Holocene Proximity to ocean cores and likely sensitivity (closed basin lake) suggests that record will contribute significantly to our understanding of marine/nonmarine climate linkages in western NAm pasadena.wr.usgs.gov/ office/galetzka/imgbank/

50 Acknowledgments NSF Grant # OEDG Program Kathy Sharum and Rhonna Hurl, BLM Chevron, USA REVS Up Program High School Teachers and Students of REVS Up Program Elizabeth Powers and Tom Osborn, CSUB Technicians pasadena.wr.usgs.gov/ office/galetzka/imgbank/

Copyright. Randall Kevin Stephenson

Copyright. Randall Kevin Stephenson Copyright By Randall Kevin Stephenson 2013 LITHOSTRATIGRAPHIC RECORD OF NORTH SODA LAKE, CARRIZO PLAIN, SAN LUIS OBISPO COUNTY, CALIFORNIA: IMPLICATIONS FOR LATE PLEISTOCENE PALEOCLIMATE IN A CLOSED HYPERSALINE