In “[meteorite-list] Holocene Extinctions and a different lake”, Ed wrote:
“I'm glad to hear that all the debate about the dating of the Lake Misssoula flooding has now been cleared up. Does the same thing hold for Lake Bonneville, and other Ice Age plains lakes?” I have PDF versions of about 70 publications about geology and paleoliminology, and chronology of Lake Bonneville. There are numerous other minor publications about Lake Bonneville. In addition, I have about a couple of dozen papers and other publications about other Ice Age pluvial lakes that existed in the Southwestern United States, including pluvial Lake Estancia in New Mexico. In none of these papers, is there any evidence of either any terminal Pleistocene impacts, including about “10,750 BCE,” or any Holocene impacts. The significant change from Ice Age pluvial lake levels in Lake Bonneville and other pluvial lakes towards modern playa lakes started about 12,600 14C yr BP (15,000 cal yr B.P.). This is long before any of your proposed impacts. This is simply the time that the colder, wetter climates of the Last Glacial Maximum transitioned to the warmer, drier conditions of the late Pleistocene and early Holocene. This change is coincident with comparable drops (regression) in lake-level in Lake Lahontan, Lake Estancia, and other southwestern pluvial lakes and with the onset of the Bolling-Allerod warming event. There is a very slight rise in lake levels to the Lake Gilbert highstand in response to climate changes associated with the Younger Dryas. There is nothing obvious in the lake sediments to indicate any direct association with any sort of extraterrestrial impact. Whatever caused the Younger Dryas climatic changes is what indirectly caused the high lake levels of Lake Gilbert. In terms of basic reading, a person can start with: Allen, B. D., 2005, Ice Age Lakes in New Mexico. in S. G. Lucas, G. S. Morgan, and K. E. Zeigler, eds., pp. 107-114, New Mexico’s Ice Ages. Bulletin no. 28, New Mexico Museum of Natural History and Science. http://geoinfo.nmt.edu/staff/allen/documents/iceagelakesnm.PDF Balch, D. P., A. S. Cohen, D. W. Schnurrenberger, B. J. Haskell, B. L. V. Garces, J. W. Beck, H. Cheng, and R. L. Edwards, 2005, Ecosystem and paleohydrological response to Quaternary climate change in the Bonneville Basin, Utah. Palaeogeography, Palaeoclimatology, Palaeoecology. vol. 221, no. 1-2, pp. 99-122. http://www.sciencedirect.com/science/article/pii/S0031018205000829 Benson, L. V., D. R. Currey, R .I. Dorn, K. R. Lajoie, C. G. Oviatt, S. W. Robinson, G. I. Smith, and S. Stine, 1990, Chronology of expansion and contraction of four great Basin lake systems during the past 35,000 years. Palaeogeography, Palaeoclimatology, Palaeoecology. vol. 78, no. 3-4, pp. 241-286. http://www.sciencedirect.com/science/article/pii/003101829090217U Benson, L. V., S. P. Lund, J. P. Smoot, D. E. Rhode, R. J. Spencer, K. L. Verosub, L. A. Louderback, C. A. Johnson, R. O. Rye, and R. M. Negrini, 2011, The rise and fall of Lake Bonneville between 45 and 10.5 ka. Quaternary International. vol. 235, no. 1-2, pp. 57-69. http://www.sciencedirect.com/science/article/pii/S1040618210004829 Louderback, L. A., and D. E. Rhode, 2009, 15,000 Years of vegetation change in the Bonneville basin: the Blue Lake pollen record. Quaternary Science Reviews. vol. 28, no. 3-4, pp. 308-326. http://www.sciencedirect.com/science/article/pii/S0277379108002680 Godsey, H. S., C. G. Oviatt, D. M. Miller, and M. A. Chan, 2011, Stratigraphy and chronology of offshore to nearshore deposits associated with the Provo shoreline, Pleistocene Lake Bonneville, Utah. Palaeogeography, Palaeoclimatology, Palaeoecology. vol. 310, no. 3-4,pp. 442-450. Oviatt, C. G., D. M. Miller, J. P. McGeehin, C. Zachary, and S. Mahan, 2005, The Younger Dryas phase of Great Salt Lake , Utah. Palaeogeography, Palaeoclimatology, Palaeoecology. vol. 219, no. 3-4, pp. 263-284. http://www.sciencedirect.com/science/article/pii/S0031018211004317 Patrickson, D. S., A. R. Brunelle, and K. A. Moser, 2010, Late Pleistocene to early Holocene lake level and paleoclimate insights from Stansbury Island, Bonneville basin, Utah. Quaternary Research. vol. 73, no. 2, pp. 237-246. http://www.sciencedirect.com/science/article/pii/S0033589409001653 Spencer, R. J., M. J. Baedecker, H. P. Eugster, R. M. Forester, M. B. Goldhaber, B. F. Jones, K. Kelts, J. Mckenzie, D. B. Madsen and S. L. Rettig, 1984, Great Salt Lake, and precursors, Utah: The last 30,000 years. Contributions to Mineralogy and Petrology. vol. 86, no. 4, pp. 321-334. http://www.springerlink.com/content/j7744044505082r0/ Maps of the pluvial lakes of the Southwest US can be found at: 1. Late Quaternary Paleohydrology of the Mojave Desert http://esp.cr.usgs.gov/info/mojave/paleoenviron.html http://esp.cr.usgs.gov/info/mojave/images/fig13.gif 2. Reheis, M,, 1999, Extent of Pleistocene Lakes in the Western Great Basin. Miscellaneous Field Studies Map MF-2323, U.S. Geological Survey, Denver, CO. http://pubs.usgs.gov/mf/1999/mf-2323/mf2323.pdf http://pubs.usgs.gov/mf/1999/mf-2323/ 3. Matsubara, Y., and A. D. Howard, nd, Spatially-explicit modeling of modern and Pleistocene runoff and lake extent in the Great Basin region, western United States. Department of Environmental Sciences, University of Virginia, Charlottesville, Virginia. http://erode.evsc.virginia.edu/papers/matsubara_Pleistocene_GB.pdf One of the stranger claims that has been made about Lake Bonneville and other pluvial lakes in the southwest is that the salt and other evaporite deposits that characterize the modern playa lakes associated with them are the result of the evaporation of sea water splashed into them from the Pacific Ocean by multiple-kilometer-high impact generated megatsunamis from a terminal Pleistocene /early Holocene impacts as argued by Tollmann and Tollmann (1994) and Knight and Lomas (2000). Now, as in either 1994 and 2000, there exists ample data, interpretations, and other information in published literature to soundly refute their arguments. The change from fresh water, pluvial lakes towards the modern saline playa lakes occurred long before their proposed impacts as documented in the above papers. The accumulation of evaporites in these lakes started thousands of years before the hypothetical impact. In addition, the geochemistry and sedimentology of the salt and other evaporites found in these lakes clearly demonstrates that they are the result of the evaporation of water carrying dissolved minerals from rocks exposed within the drainage basin of these lakes as discussed by Hart et al. (2004), Spencer et al. (1985a, 1985b). Also, despite the continuous record of lake sedimentation recovered in cores from Lake Bonneville and other lakes, there is a complete of either an event bed of deposits that such an event would most certainly have left behind. The many problems with the arguments of Tollmann and Tollmann (1994), which Knight and Lomas (2000) simply ignore, are discussed in detail by Deutsch et al. (1994). References Cited, Deutsch, A., C. Koeberl, J. D. Blum, B. M. French, B. P. Glass, R. Grieve, P. Horn, E. K. Jessberger, G. Kurat, W. U. Reimold, J. Smit, D. Stöffler, and S. R. Taylor, 1994, The impact-flood connection: Does it exist? Terra Nova. vol. 6, pp. 644-650. http://onlinelibrary.wiley.com/doi/10.1111/j.1365-3121.1994.tb00532.x/abstract Christopher Knight and Robert Lomas. 2000 Uriel's Machine: ‘The Ancient Origins of Science. Element Books Ltd. 480 pp. Kristan-Tollmann, E. and A. Tollmann, 1994, The youngest big impact on Earth deduced from geological and historical evidence. Terra Nova. vol. 6, no. 2, pp. 209-217. http://onlinelibrary.wiley.com/doi/10.1111/j.1365-3121.1994.tb00656.x/abstract Hart, W. F., J. Quade, D. B. Madsen, D. S. Kaufman, and C. G. Oviatt, 2004, The 87Sr/86Sr ratios of lacustrine carbonates and lake-level history of the Bonneville paleolake system. Geological Society of America Bulletin. vol. 116, no. 9-10, pp. 1107-1119. Spencer, R. J., H. P. Eugster, and B. F. Jones, 1985a, Geochemistry of great Salt Lake, Utah II: Pleistocene-Holocene evolution. Geochimica et Cosmochimica Acta. vol. 49, no. 3, pp. 739-747 http://www.sciencedirect.com/science/article/pii/0016703785901681 Spencer, R. J., H. P. Eugster, B. F. Jones, and S. L. Rettig, 1985b, Geochemistry of Great Salt Lake, Utah I: Hydrochemistry since 1850. Geochimica et Cosmochimica Acta. vol. 49, no. 3, pp. 727-737 http://www.sciencedirect.com/science/article/pii/001670378590167X Best wishes, Paul H. ______________________________________________ Visit the Archives at http://www.meteoritecentral.com/mailing-list-archives.html Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
