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USDA/ WRI Intern Report

CSU Bakersfield Sierra River Discharge Project

Latest Pleistocene through Holocene Lake

Levels from Tulare Lake, CA: Testing results

using the Smear Slide Technique

Kelsey Padilla

CSU Bakersfield

Term of Internship: Winter 2013 – Summer 2014

Advisor: Dr. Robert Negrini, CSU Bakersfield

Date Submitted: 9-16-2014

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Table of Contents

Title Page……………………………………………………………………….…....1

Table of Content…………………………………………………………………......2

Acknowledgements……………………………………………………………….....3

Executive Summary……………………………………………………….……........4

Project Objectives………………………………………………………………........6

Project Approach and Tasks...……………………………………….………………7

Project Outcomes, Conclusions, and Future Work…………………….…………….8

Appendices

References………………………………………………………..…………10

Figures……………………………………………………………………….12

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Acknowledgements

This project was supported by Agriculture and Food Research Initiative Competitive Grant no.

2011-38422-31204 from the USDA National Institute of Food and Agriculture.

Funding for the purchase of the UIC Coulometer CM135, Costech 4010 Elemental Analyzer, and

Malvern Mastersizer 2000 laser particle analyzer was provided by the US Department of

Education Award #P031C080013-09. The NSF DHR CREST Award #1137774 also provided

infrastructural support and salary support for other team members not supported by USDA funds.

A special thank you to Dr. Robert Negrini, Ashleigh Slaughter-Blunt, and Kathy Randall for

their assistance with my education on the Costech 4010 Elemental Analyzer, the UIC

Coulometer CM135, and the Malvern Mastersizer 2000 laser particle analyzer. I would also like

to thank them for allowing me to work on the CSU Bakersfield Sierra River Discharge project. I

would also like to thank Dr. Scott Starratt of the United States Geological Survey (USGS) for his

assistance and analysis of the diatoms in this study.

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Executive Summary

CSU Bakersfield (CSUB) is in the process of developing a multifaceted lacustrine dataset from

which Sierran River discharge into the southern San Joaquin Valley for the past 20,000 years

can be inferred. This composite record will approach decadal scale resolution and will lead to

improved forecasting for Sierran discharge over the next several decades after this record is

compared to an improving collection of coeval records of sea-surface temperatures of the Pacific

Ocean. Reported herein is a component of this study on the detailed lithologic description of

Tulare Lake sediments using the smear slide technique.

Prior to diversion of streamflow for the purpose of irrigation, Tulare Lake (Figure 1) was the

largest fresh water lake west of the Great Lakes (Preston, 1981). At that time, its lake level (a

bold line in Figure 2) was linearly related to the discharge of four Sierran streams, the Kern,

Tule, Kaweah, and Kings Rivers (Atwater et al., 1986). This relationship is the basis for

reconstructing the discharge of these rivers for the past 20,000 years by determining the surface

elevation vs. age of Tulare Lake through a study of its sediments and landforms. Negrini et al.

(2006) mapped an ancient shoreline and the lithology of associated sediments in a series of 2 sets

of trenches (sets 1-5 and A-D) and a preexisting core to obtain a low resolution record of lake

elevation through time (Figure 3 and 4). This record was found to be consistent with respect to

timing of lake-level changes to results from two other lakes from southern California (Kirby et

al., 2012), thus these changes likely represent regional climate rather than geomorphological

processes local to the particular lakes. Kirby et al. 2012's earlier work (Figure 5) may be

compared with the Paleolake-level history that was constructed through the lithologic mapping

of trenches (Figure 3) to show that the high lake levels predicted are consistent with those found

in other California lakes.

The core-based, lake-level proxy record of Blunt (2013) and Blunt and Negrini (in review) for

Tulare Lake, CA extended the trench-based record of Negrini et al. (2006) back to ~20,000 years

ago. Furthermore, the former has an improved resolution corresponding to one sample every ~50

years, making it more useful towards decadal-scale forecasts of recharge. The study

corresponding to this report uses the smear slide technique of Schnurrenberger et al. (2003) to

test the findings of Blunt (2013). The technique involves smearing chemically and physically

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unaltered sample onto a glass microscope slide using Norland optical cement as a medium and

curing the sample with an ultraviolet light. Samples were taken from 39 to 442 cm of the core

and each sample was spaced 5cm apart. Thus each sample represents an average of 40 years of

sedimentation separated by an average of 70-100 years. The resulting descriptions, detected

features diagnostic of both deep, freshwater and shallow, brackish water paleoenvironments, thus

providing a test of the previous lake-level records.

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Project Objectives

Water is an essential resource for agriculture in the Central Valley of California and forecasting

the amount of available water in the future is a primary objective to many agencies and

industries. This project relates to a potential career path for me in the United States Department

of Agriculture (USDA), as it deals with environmental concerns that would be addressed by a

geologist working for this specific department. The U.S. Department of Agriculture is widely

concerned with providing water to farmers and other agriculture based companies, as they

provide food for consumers all across the U.S. Forecasting water supply dynamics in Kern

County is the first step in creating strategies for water storage solutions affecting both residential

and business uses.

Tulare Lake sediments, as well as sediments from other deep lake settings, accumulate more or

less continuously throughout time. Because they often are associated with high deposition rates,

these sediments also offer a detailed repository of measurable quantities that inform us of lake

level, hence, stream discharge. Studies of these sediments allow for reconstruction of the lake

level and, hence, stream flow input from surrounding Sierran streams, more specifically, the

Kern, Tule, Kaweah, and Kings Rivers. Several geochemical and geophysical proxies were used

to analyze the Tulare Lake sediment in this manner. I was placed on this previous project to

collect data for another student within the program, who completed the analysis for the overall

project. Following the completion of the project, I was then given the task to check previous

results using another type of study. The following method was used to complete my research

over the course of the internship.

My objectives were to make and analyze smear slides resulting in a more in-depth sediment

analysis. Smear slides offer a cheap, powerful, rapid analytical tool to identify components and

origins of lake sediment. They also offer a quick semi-quantitative measure of relative changes

in components in a lithostratigraphic section. (Schnurrenberger et al., 2003)

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Project Approach and Tasks

To complete the analysis on the sediment, I first had to determine the best method to use to make

each smear slide. After reading several studies using the technique, I decided upon the

Schnurrenberger (2003) method, which can be found on the University of Minnesota LacCore:

National Lacustrine Core Facility web page (https://tmi.laccore.umn.edu/). This method uses

chemically and physically unaltered core sediment to fashion the slides and complete the

analysis.

To begin, samples from a core depth ranging from 39 to 442 cm below ground surface level were

taken at 5cm intervals, which spans from approximately 2,800-18,500 cal yr BP. Each sample

interval represents an average of 40 years of sedimentation separated by an average of 70-100

years. This interval corresponds with the Blunt (2013) study and uses the same core material

previously gathered. A small amount of each sample was then smeared onto an individual slide

using a few drops of deionized water and a small metal spatula. The slide was allowed to dry on

a hot plate for several minutes and removed to completely cool before further handling. A cover

slip was placed on top of the sample, cemented using Norland optical cement as a medium, and

cured under an ultraviolet light. The analysis was conducted using a petrographic microscope for

both organic and inorganic material.

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Project Outcomes, Conclusions, and Future Work

With respect to scientific results, the analysis of data is still in progress, but the initial results ares

promising. Thus far, the results are consistent with the predictions of Blunt (2013). For example,

at the lower end of the record, the smear slides from within the interval hypothesized to contain

sand-sized grains of Tioagan-aged glacial outwash from the Sierra Nevada ice cap, have, as

predicted, little to no organic matter or carbonate present and are characterized by sand grains of

granitic composition (Table 1 and Figure 6). Also, in the time interval from 2,500 to 1,800 cal.

yr. BP, Blunt (2013) suggests shallow, freshwater lake conditions due to a low total inorganic

carbon (TIC) value and relatively coarse grains. The predictions are consistent with observations

of pristine sponge spicules and the pollen species Typha (i.e. cattail) in the smear slides from the

corresponding depth interval (Table 1 and Figure 7). Also consistent with predictions for this

interval are fluctuating levels of clay and silt, and occasional coarse grain. Future work on this

project will include an in-depth 5-cm interval diatom analysis completed by Dr. Scott Starratt of

the United States Geological Survey (USGS) and my continued smear-slide analysis.

Regarding my development as a scientist, I was able to learn several skills that will be useful

both with respect to completion of my thesis, the reinforcement of what I learned in coursework,

and research and presentations conducted in the workplace after I graduate. For example, I

learned how to sample and handle delicate sediment cores that had to be preserved for future

study. Also, I attained the knowledge of how to prepare smear slides and analyze sediment

under a petrographic microscope for both organic and non-organic components. From completed

presentations at local meetings during the course of my internship, I also acquired several

acquaintances with other local geologists and micro-paleontologists that share a common interest

in lake and sediment study. These connections will follow me through the remainder of my

education and eventually into my career.

I will be continuing the opportunity given to me to continue the Tulare Lake study as part of my

Master's thesis at California State University Bakersfield, where I have was accepted as a

geology student in the Master's of Science program and where I am fully funded by a

combination of sources including the CSUB NSF CREST grant and hopefully continuing support

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from the WRPI USDA grant. This internship was a major stepping stone with which to continue

my education and reaching my goal of obtaining a profession within the U.S. Department of

Agriculture.

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References

Atwater, B.F., Adam, D.P, Bradbury, J.P., Forrester, R.M., Mark, R.K., Lettis, W.R., Fisher,

G.R., Gobalet, K.W., Robinson, S.W., 1986. A fan dam for Tulare Lake, California, and

implications for the Wisconsin glacial history of the Sierra Nevada. Geological Society of

America Bulletin 97, p. 97-109.

Benson, L.V., 2004. Western lakes, in: Gillespie, A.R., Porter, S.C., Atwater, B.F. (eds.), The

Quaternary Period of the United States, Elsevier, Amsterdam, p. 185-204.

Benson, L.V., Lund, S.P., Smoot, J.P., Rhode, D.E., Spencer, R.J., Verosub, K.L., Louderback,

L.A., Johnson, C.A., Rye R.O., Negrini, R.M., The rise and fall of Lake Bonneville between 45

and 10.5 ka, Quaternary International, Volume 235, Issues 1–2, 15 April 2011, Pages 57-69

Blunt, A. B., Negrini, R. M., Randall, K. M., Garcia, E.l, Wilson, J., Wilson, J.M., Chauhan, J.,

Chehal, R., Shurbaji, H., and Shugart, J., 2012, Supplementing a Tulare Lake, CA Late

Pleistocene to Holocene Lake-level Record using Geochemical and Geophysical Proxies from

Core Sediments: Geological Society of America Abstracts with Programs, v. 44, no. 7, p, 84

Cohen, A.S., 2003. Paleolimnology, Oxford Univ. Press, 500 p.

Kirby, M.E., S.R. Zimmerman, W.P. Patterson, J.J. Rivera, 2012., A 9170-Year Record of

Centennial-to-Multi Centennial Scale Pluvial Events From Coastal Southwest North America: A

Role for Atmospheric Rivers, Quaternary Science Reviews. 46, 57-65

Meyers, P.A., Lallier-Verges, E. 1999. Lacustrine sedimentary organic matter records of Late

Quaternary paleoclimates, Journal of Paleplimnology 21, p. 345-372.

Negrini, R.M., Wigand, P.E., Drauker, S., Gobalet, K., Gardner, J.K., Sutton, M.Q., Yohe II,

R.M., 2006. The Rambla highstand shoreline and the Holocene lake-level history of Tulare,

Lake, California, USA. Quaternary Science Reviews 25, p. 1599-1618.

Page, R.W. 1986. Geology of the fresh ground-water basin of the Central Valley, California,

with texture maps and sections. US Geological Survey Professional

Paper 1401C.

Preston, W.L., 1981. Vanishing Landscapes: Land and Life in the Tulare Lake Basin, University

of California Press: Berkeley and Los Angeles, California.

Schnurrenberger, D.S., J.M. Russell, and K.R. Kelts, 2003. Classification of lacustrine sediments

based on sedimentary components. J. Paleolimnology 29: 141-154

Sperazza, M., Moore, J. N., Hendrix, M. S., 2004. High-resolution particle size analysis of

naturally occurring very fine-grained sediment through laser diffractometry. Journal of

Sedimentary Research 74, p. 736-743.

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Wigand, P, 2013, Southwestern North America, Encyclopedia of Quaternary Science 2nd

edition, v. 4, p. 142-155

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Figures

Fig. 1) Simplified geologic map of Tulare Lake.

Fig.2) Historic and modeled lake-level history which indicates Tulare Lake level is primarily

controlled by Sierran runoff (after Atwater et al, 1986). The pre-1850 part of the curve is the

most important as this is the point before which water was not being diverted for agricultural

purposes.

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Fig. 3) Location of trenches in Negrini et al (2006) and cores TL05-4A and TL05-4B used for

this project.

Fig. 4) Paleolake-level history constructed from lithologic mapping of trenches from different

elevation and a basin bottom core (Negrini et al, 2006).

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Fig. 5) C/N ratios and grain size data from other California lakes, Lower Bear Lake and Lake

Elsinore (Kirby, in press), indicate lake events with similar timing to each other and with the

results of our research (Figure 5).

Fig. 6) Components of the smear slide corresponding to the Tioagan-aged glacial outwash.

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Fig. 7 Components corresponding to the uppermost section of the core.

Table 1. Predicted results from Blunt (2013) study and preliminary results.