A revised chronology for the last Pleistocene lake cycle in the central Lahontan basin
Amérique du Nord ; Datation radiocarbone ; Domaine aride ; Etats-Unis ; Great Basin ; Géographie de l'Amérique ; Lac ; LakeLahontan ; Niveau lacustre ; Paléohydrologie ; Pléistocène supérieur ; Quaternaire zones moyennes
Radiocarbon dates of plant materials from packrat middens, in conjunction with radiocarbon dates of archaeological materials, provide evidence that the last high stand of Pleistocene LakeLahontan terminated before 12,070 yr B. P. This new
information suggests that the last major fluctuation in the level of LakeLahontan was approximately synchronous with those of Lakes Bonneville and Russel, and that these three lakes probably responded contemporaneously to the same regional paleoclimatic
Late Pleistocene and late Holocene lake highstands in the Pyramid Lake subbasin of LakeLahontan, Nevada, USA
C 14 dating ; Lake ; Lake level ; Nevada ; Palaeoclimate ; Quaternary ; Shoreline ; Stratigraphy ; United States of America
Shoreline geomorphology, shoreline stratigraphic position, and radiocarbon dates of organic material obtained from trench and quarry exposures provide evidence for 2 significant post-Lahontan highstand lake transgressions in the Pyramid Lake
subbasin. The AA. briefly compare their findings to previously published post-highstand Lahontanlake-level curves and other regional paleoclimate indicators.
The purpose of this paper is to illustrate the strengths and weakness of using lake size and, in particular, lake level, as an indicator of climatic change. The lake-level record for one closed-basin system (LakeLahontan) is examined in terms
of existing topographic and hydrologic features that have constrained its variation. The total surface areas of lakes in a basin is shown to be a more appropriate measure of change in the hydrologic balance.
Geomorphology of a dry valley : Adrian Pass, Lahontan Basin, Nevada
Lake ; Nevada ; Palaeogeomorphology ; Quaternary ; United States of America ; Valley
Previous studies of Adrian Pass concluded that it was an abandoned channel of the Walker River. The evidence presented in this study suggests that Adrian Pass was formed by overflow of LakeLahontan, the second-largest Great Basin Quaternary lake
, from the lower Walker River Basin to the Carson Desert Basin. Walker River occupancy of Adrian Pass during post-LakeLahontan time was relatively brief. - (SLD)
Uranium-series age estimates and paleoclimatic significance of pleistocene tufas from the Lahontan Basin, California and Nevada
The AA. report data on the distribution of the isotopes of uranium and thorium in water and sediment from two drainage systems in the Lahontan Basin. These data are used to perform model calculations of ages of tufa samples from the Lahontan Basin
. The calculated ages are then used to construct a tentative lake-level chronology for both the Walker lake and Pyramid Lake subbasins.
, by the major and minor element chemistry of its glass, and by its stratigraphic position with respect to other tephra layers. When the tephra fell, pluvial LakeLahontan stood between 1256 and 1260 m, and that immediately thereafter the lake rose to at least
1275 m. The LakeLahontan area has been affected by isostatic subsidence and rebound in response to changing water loads, so that caution is required in the use of lakeshore elevations in correlation.
The Trego Hot Springs tephra bed is a silicic tephra about 23,400 yr old, found at several localities in pluvial lake sediments in northern Nevada, southern Oregon, and northeastern California. It has been characterized petrographically
Paleomagnetic investigation of lakeLahontan sediments and its application for dating pluvial events in the Northwestern Great Basin
A comparison of paleomagnetic secular variation in sediment of Pleistocene Lakelahontan in the northwestern Great basin with secular variation in lake sediment in the Mono Basin, California, indicates that LakeLahontan was in the valley
of the Truckee River between Pyramid Lake and Wadsworth, Nevada, from about 19,000 to 13,000 yr B.P. On the basis of field mapping and tephrochronology, the sections of older lacustrine sediments are not coeval. The apparent, but erroneous, correlation of those
Factors affecting 14C ages of lacustrine carbonates : timing and duration of the Last Highstand Lake in the Lahontan Basin
C14 dating ; California ; Carbonate ; Geochemistry ; Lake ; Lake level ; Nevada ; Palaeogeography ; United States
The purposes of this paper are to determine when corrections for low initial 14C/c ratios in lake water should be made and which Lahontan carbonates listed in published carbonate 14C data bases (e.g., Benson, 1978, 1981; Benson et al., 1991) have
of highstand carbonates and used to estimate the timing and duration of the last LakeLahontan highstand.
Paleoclimatic significance of lake-level fluctuations in the Lahontan Basin
Bilan énergétique ; Etats-Unis ; Fluctuation de niveau lacustre ; Géographie physique ; Hydrologie ; Lac ; LakeLahontan ; Modèle ; Modèle mathématique ; Nevada ; Paléoclimatologie ; Paléohydrologie ; Pyramid Lake ; Quaternaire
la masse optique de l'air. Après avoir été testé sur le Pyramid Lake au Nevada à partir de données historiques le modèle a été utilisé pour simuler les changements de niveau, de surface et de volume du paleo LakeLahontan. Les résultats de la
Response of alluvial fan systems to the late Pleistocene to Holocene climatic transition : contrasts between the margins of pluvial lakesLahontan and Mojave, Nevada and California, USA
Alluvial cone ; California ; Climatic variation ; Holocene ; Lake ; Lake level ; Nevada ; Palaeo-environment ; Palaeobotany ; Palaeoclimate ; Pleistocene ; United States of America
to the early Holocene, may be due to climatic, vegetation, or other differences between the fan environments. During the late Pleistocene, both fan systems terminated in pluvial lakes, LakeLahontan in Nevada and Lake Mojave in California. In both cases, dated
lake shoreline provide good time-lines for the correlation, relative dating and interpretation of the fan sequences.
The LakeLahontan highstand : age, surficial characteristics, soil development, and regional shoreline correlation
California ; Climatic variation ; Lake ; Lake level ; Nevada ; Palaeosol ; Pedogenesis ; Pleistocene ; Quaternary ; Shoreline ; Soil properties ; Stratigraphic correlation ; United States of America
The LakeLahontan basin has been the site of numerous pluvial lakes during the Pleistocene. The AA. address the question of whether or not the highest remnant shoreline features around the perimeter of the lake were produced during the most recent
Paleomagnetic investigation of the Bonneville Alloformation, Lake Bonneville, Utah
California ; Geochronology ; Lacustrine sediment ; Lake level ; Nevada ; Palaeo-ecology ; Palaeomagnetism ; Pleistocene ; Quaternary ; United States of America ; Utah
Paleomagnetic secular variation in a portion of the Bonneville Alloformation is compared with secular variation in lacustrine sediments in the Mono Basin, California, and with secular variation in LakeLahontan sediments in the northwestern Great
Basin. The deposition occurred during a transgressive stage of Lake Bonneville and coincided with a wet period in the Lahontan Basin.
Late Quaternary history of the lower Walker River and its implications for the Lahontan paleolake system
The history of Adrian Valley demonstrates the importance of geomorphic processes in causing changes in closed-lake levels during late Quaternary time. The lacustrine history of each subbasin is controlled not only by paleoclimatic change, but also
Correlation of Late Quaternary tephra Layers in a long pluvial sequence near Summer Lake, Oregon
Datation ; Domaine aride ; Etats-Unis ; Géographie de l'Amérique ; Oregon ; Pacific States ; Paléolac ; Pléistocène moyen ; Pléistocène supérieur ; Quaternaire zones moyennes ; Summer lake, région ; Sédiment lacustre ; Séquence pluviale
. Helens, Washington, at Crater Lake, Oregon, and in northwestern Nevada in the deposits of pluvial LakeLahontan. These seven tephra beds are from 6800 to about 90,000 yr old. Extrapolation of these ages through assumption of constant depositional rate
Near Summer Lake in southern Oregon, 54 tephra beds of late Quaternary age are exposed in pluvial lake sediments of lake Chewaucan. Seven of the tephra beds near the top can be correlated with tephra deposits younger than 117,000 yr at Mount St
implies an age of more than 335,000 yr for the bottom of the exposed section at Summer Lake.
Mapping the Great Lakes. The period of imperial rivalries 1700-1760
Amérique du Nord ; Carte ancienne ; Cartographie ; Great Lakes ; Histoire de la géographie ; Siècle XVII-XVIII ; Technique cartographique
Les premières cartes de Bellin datent de 1743. Auparavant, les cartes imprimées se basaient sur la cartographie de de l'Isle et La Lahontan (fin du XVII). Après 1740, l'établissement de cartes originales a porté de plus en plus sur des régions
A reassessment of U-Th and C 14 ages for Late-Glacial high-frequency hydrological events at Searles Lake, California
C 14 dating ; California ; Climatic variation ; Dating ; Evaporite ; Lacustrine sediment ; Lake level ; Lateglacial ; Pleistocene ; Pluvial ; Quaternary ; Th/U dating ; United States of America ; Water balance
The AA. discuss the timing of the last, and most dramatic, pluvial event recorded in LakeLahontan and Searles Lake, and of distinct dry periods recorded as evaporite layers in the Searles basin. The last major pluvial events in these closed basins
Africa ; C 14 dating ; Climatic variation ; Global change ; Lake level ; North America ; Oxygen 18 ; Palaeoclimate ; Palaeohydrology ; Precipitation ; Quaternary ; World
abrupt warming. At about this time, a major change in the pattern of global rainfall occured. Lake Victoria was rejuvenated, the Red Sea freshened and LakeLahontan dessicated. For the AA., the onset of the Bølling-Allerød warm interval appears to have
been marked by an abrupt reorganization of the Earth's climate system. Therefore the proposed linkage between the size of African closed basin lakes and insolation cycles must be reexamined.