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HAMEjAIdR/k4W' U 1980 1989 The Geology of North America Volume K-2 QuaternaryNonglacial Geology: Conterminous U.S. Edited by Roger B. Morrison Morrison and Associates 13150 West Ninth Avenue Golden, Colorado 80401 t234oo051o(0 1991 931,041090035 9303 6 FDR 4ASTE TDR U ,rWRSITYOF NEVADAS LAS VEIM WI-li LBRARY 6-, Acknowledgment Publication of this volume, one of the synthesis volumes of The Decade of North American Geology Project series, has been made possible by members and friends of the Geological Society of America, corporations, and government agencies through contributions to the Decade of North American Geology fund of the Geological Society of America Foundation. Following is a list of individuals, corporations, and government agencies giving and/or pledging more than $50,000 in support of the DNAG Project: Amoco Production Company Pennzoil Exploration and ARCO Exploration Company Production Company Chevron Corporation Phillips Petroleum Company Cities Service Oi and Gas Company Sbell Oil Company Diamond Shamrock Exploration Caswell Saver Corporation Standard Oil Production Company Oryx Energy Company (formerly Exxon Production Research Company Sun Exploration and Production Getty Oil Company Company Gulf Oil Exploration and Production Superior Oil Company Company Tenneco Oil Company Paul V. Hoovler Texaco, Inc. Kencon Minerals Company Union Oil Company of California Kerr McGee Corporation Union Pacific Corporation and Marathon Oil Company its operating companim Maxus Energy Corporation Union Pacific ReOOuMcs company McMoRan 0i and Gas Company Union Pacific Railroad Mobil Oi Corporation Company Occidental Petroleum Corporation Upland Ilndusuries Corporation US. Department of Energy Data *1991 by The Geological Society of America, Inc= Lxary of Congress Catalogtng-ln-Publication All rights reserved. Quaternary nonglacial geology : conterminous US. / edited by Roger B. Mo-rison. p. an. - (The Geology of North America; v. K-2) materials aubject to thiso pyoty and included . Includes bibliographical references and index. n30J110 yslume may bpoboxcoped fixr thedoncoorndrcial ISBN 0-8137-5215-9 in ientiUicoreductiionalsed adv'ainCcM'L 1. Geology, Stratigraphic-Quaternary. Z Geology-United States. L Morrison, Roger B (Roger Barron), 1914- . H.Series. DAp ht is not caimed on any material prepared, QE696.Q336 1991 arc sovernmntereiployees within thescope oftheir b 551.7'9'0973-dc2O 91-23046 aP bployment. Published by The Geological Society of America. In= 3300 Penrose Place, P.O. Box 9140, Boulder. Colorado g3030 Printed in USA. Cover Photo: East bluff of the Walker River viewed from middle of Weber the Eetza Alloformation (130-350 ka) in Lake Lahontan's northern aubbasins. gravel Damn At least two million yeams of Lake Lahontan lacutrine and subaerial history Below another unconformity is 6 to 10 m of darker gray, chiefly lacustrine are ahown here in about 42 m of atrata in the Walker Like basin, the aouthern and sand (the upper pre-Eetza unit of Morrison and Davis, 1984b, p. 24, which most of Lake Lahontan's aubbasirs The top 6 i (light gray and light yellowish contains the I Ma Glass Mountain G tephra layerý Beneath a marked erosional gray) are lacustrine gravel and sand of the middle member of the Sehoo Allofor unconformity and extending to below the modem flood plain of the Walker River mation (about 13 ka) unoonformably overlying eolian and slopewash sand bear is 20+ m oftan-gray alluvial gravel and and intercalated with many palemols--a ing the Wyemaha Geosol (35-130 ka). Beneath another unconformity is 9 to unit considerably older than the Lovelock Alloformation in the northern basins. 10 m of medium to pale gray lazustrine gravel, aand, and salt equivalent to parts of Photo by R. B. Morrison. 10 9 8 7 6 5 4 3 2 1 ii .4 iv Contents K.Ar dauing of Quaternary olcanwc rocks ....................................... 49 P. L. Damon Fission-track dating ..................................................... 53 C. W. Naescv and N. D. Namser Conventionaluranium-serles and uranium-trenddating ............................... 55 B.J. Szabo and J. N. Rosholt Paleomagneticdating .................................................... 60 J. C. ddicoast Th7emo/-inescence dating ................................................ 61 S. L Forman and M. N. Machette Amino aid geochronology of foil mollusks ...................................... 65 D. L. Muhs 4. Quaternaryvolcanism in the western conterminous United States ..................... 75 R. G. Luedke and R. L. Smith 5. Quaternarytephrochronology ................................................... 93 A. M. Sama-Wojcicki and J. 0. Davis 6. Tephrochronologiccorrelation of upper Neogene sediments along the Pacific margin, conterminous United States ................................... 117 A. M. Sarna-Wojcicki, K. R. Lajoie, C. E. Meyer, D. P. Adam, and H. J. Rieck REGIONAL CHAPTERS 7. Quaternarygeology of the Pacific margin ........................................ 141 W. R. DuprE, R. B. Morrison, H. E. Clifton, K. R. Lajoie, D. J. Ponti, C. L Powell II, S. A. Mathieson, A. M. Sarna-Wojcicki, E. L. Leithold, W. R. Lettis, P. F. McDowell, T. K. Rockwell, J. R. Unruh, and R. S. Yeats Imtroducion ......................................................... 141 W. RLDupre and H. E.CMifton Quaternarycoas andshatow-mrine facies sequenc= Northern Ca/ifornia and die Pac#1c Northwest .................................... 143 H. E. Clifton and E. L Leithold Quaernary.gmradgwkp and geomorphic surfaces of de Wruilamerte Valley. Oregon................................................. 156 P. F. McDowdl Qaernarygeolov of the Great Vaet. Californu ................................. 164 W. f. Leuti and J. R. Unruh Quaternarygeology of te So-them CaliforniaCoast Ranges .......................... 176 W. R. Duprh Quaterniaygeology of the Ventura and Los Angeles basm Cahjbnia .......................................................... 185 R.I Yeats and T. K. Rockweil The Geology of North America Vol. K-2. Quaternarv Nonglactal Geology. Conterminous US. The Geologicai Society of Amenca. 1991 Chapter 3 Dating methods applicableto the Quaternary John N. Rosholt* US GeologicalSurvey. MS 963. Box 25046. Denver FederalCenter. Denver. Colorado 80225 Steven M. Colman US GeologicalSurvey. Woods Hole. Massachuseas 02543 Minze Stuiver Departmentof GeologicalSciences and Quaternarv Research Center. Universuty of Washington, Seattle, Washington 98195 Paul E. Damon Departmentof Geosciences. Universaty of Arizona. Tucson. Arizona 85721 Charles W. Naeser. Nancy D. Naeser, Barney J. Szabo. and Daniel R. Muhs US GeologicalSurvey, MS 424, Box 25046. Denver FederalCenter. Denver, Colorado 80225 Joseph C. Liddicoat Universigv of Ca'fornia,Santa Cruz California95064 Steven L Fornan Institute of Arctic and Alpine Research and Departmentof GeologicalSciences. University of Colorado.Boulder, Colorado 80309 Michael N. Machette and Kenneth L Pierce U.S GeologicalSurvey, MS 913. Box 25046, Denver Federal Center.Denver. Colorado 80225 SUMMARY OF QUATERNARY ments and should not be considered definitive; the entries for DATING METHODS applicability, age range, and optimum resolution are particularly interpretive. Details concerning assumptions, analytical tech Steven M. Colman and Kenneth L Pierce niques, uncertainties, and interpretations should be obtained from specialized references using the key references in Plate 2 as a INTRODUCTION AND COMPILATION OF guide. The dating methods described range from well-known and QUATERNARY DATING METHODS established techniques to experimental procedures whose results are subject to considerable interpretation. A wide variety of dating methods are used in Quaternary Key references included on Plate 2 are intended as an entry research. and each method has many applications and limitations. into the vast literature on dating methods-, space prohibits a more Because of this variety, we cannot discuss the applications and complete listing. We have emphasized recent review papers and limitations of all methods here. The more versatile and widely notable examples of applications as sources of additional refer used methods, including 14C, K/Ar, fission-track, U-series, pa ences and information. Dating methods discussed in other leomagnetism, thermoluminescence, and amino acid dating are sections of this chapter are indicated by asterisks in the summary treated more comprehensively in this chapter than other methods table. The first five references are reviews or edited volumes that that are shown on the summary chart. The summary chart is discuss Quaternary dating methods in general; references 6-11 provided here to give an overview of dating work and research are edited volumes that focus on individual methods or closely for the Quaternary. related methods. In the interest of brevity and clarity, we have not This summary consists mainly of a table (Plate 2) that is cited individual papers in these edited volumes. Some dating modified and updated from Colnan and Pierce (1977, Plate I, methods are based on fundamental geological principles, such as ref. 66). The table isintended as an overview and concise guide to stratigraphy, for which references are deemed unnecessary here. Quaternary dating methods. It contains many subjective judg- For the purpose of our discussion and summary table, it is useful to classify dating methods, which can be done in a variety of ways. Perhaps the simplest classification is one that groups methods that share similar assumptions, procedures, or applica- Rmholt. J. N., Columan. S.
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  • Trackflow, a New Versatile Microscope System for Fission Track

    Trackflow, a New Versatile Microscope System for Fission Track

    https://doi.org/10.5194/gchron-2019-13 Preprint. Discussion started: 23 October 2019 c Author(s) 2019. CC BY 4.0 License. Technical note: TRACKFlow, a new versatile microscope system for fission track analysis Gerben Van Ranst1, Philippe Baert2, Ana Clara Fernandes2, Johan De Grave1 1Department of Geology, Ghent University, Ghent, 9000, Belgium 5 2Nikon Belux, Groot-Bijgaarden, 1702, Belgium Correspondence to: Gerben Van Ranst ([email protected]) Abstract. We here present TRACKFlow, a new system with dedicated modules for the fission track (FT) laboratory. It is based on the motorised Nikon Eclipse Ni-E upright microscope with the Nikon DS-Ri2 full frame camera and is embedded within the Nikon 10 NIS-Elements Advanced Research software package. TRACKFlow decouples image acquisition from analysis to decrease schedule stress of the microscope. The system further has the aim of being versatile, adaptable to multiple preparation protocols and analysis approaches. It is both suited for small-scale laboratories and is also ready for upscaling to high-throughput imaging. The versatility of the system, based on the operators’ full access to the NIS-Elements package, exceeds that of other systems for FT and further expands to stepping away from the dedicated FT microscope towards a general microscope for 15 Earth Sciences, including dedicated modules for FT research. TRACKFlow consists of a number of user-friendly protocols which are based on the well plate design that allows sequential scanning of multiple samples without the need of replacing the slide on the stage. All protocols include a sub-protocol to scan a map of the mount for easy navigation through the samples on the stage.