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Late Quaternary lake-level record from Northern Eurasia

Late Quaternary lake-level record from Northern Eurasia
Atmospheric circulation ; Climatic variation ; Eurasia ; Glaciation ; Insolation ; Lake ; Lake level ; Monsoon ; Palaeo-environment ; Quaternary
This paper documents changes in the regional climates of northern Eurasia, as shown by lake records, through the late Quaternary. There is a gradual transition to modern conditions after ca. 5000 yr B.P. Although these broad-scale patterns
are interrupted by shorter term fluctuations, the long-term trends in lake behavior show a clear response to changes in insolation and glaciation.

Fish remains from Homestead Cave and lake levels of the past 13,000 years in the Bonneville Basin

Fish remains from Homestead Cave and lake levels of the past 13,000 years in the Bonneville Basin
C 14 dating ; Geochemistry ; Geochronology ; Ichtyofauna ; Isotope dating ; Lake ; Lake level ; Palaeo-environment ; Quaternary ; Salinity ; Salt lake ; Taxonomy ; United States of America ; Utah
The AA. present the species composition, size structure, and Sr 87/Sr 86 ratios of the precisely dated ichthyofauna from Homestead Cave, Utah, and discuss their implications for terminal Pleistocene and Holocene lake history in the Bonneville basin.

Underwater dissolutional pitting on dolostones, Lake Huron-Georgian Bay, Ontario

Underwater dissolutional pitting on dolostones, Lake Huron-Georgian Bay, Ontario
Biogenic process ; Canada ; Carbonate dissolution ; Carbonate rock ; Chemical erosion ; Geochemistry ; Lake ; Lake level ; Ontario ; Shoreline ; Typology ; Water
This paper examines underwater dissolutional pitting along the dolomitic shorelines of the Bruce Peninsula around Tobermory, Ontario. It describes the morphology and spatial distribution of pits beneath the modern lake level, and develops
a morphological classification of the pit types. A model to explain pit genesis including initiation and enlargement incorporating this post glacial lake level history is proposed.

Changes in the bathymetry and volume of glacial Lake Agassiz between 11,000 and 9300 C 14 yr B.P.

Changes in the bathymetry and volume of glacial Lake Agassiz between 11,000 and 9300 C 14 yr B.P.
Bathymetry ; Deglaciation ; Glacial lake ; Lacustrine sediment ; Lake ; Lake level ; Model ; North America ; Palaeo-environment ; Quaternary
Amérique du Nord ; Bathymétrie ; Déglaciation ; Lac ; Lac glaciaire ; Lake Agassiz ; Modèle ; Niveau lacustre ; Paléo-environnement ; Quaternaire ; Sédiment lacustre
The volume and surface area of glacial Lake Agassiz varied considerably during its 4000-year history. Computer models for 7 stages of Lake Agassiz were used to quantify these variations over the lake's early history, between about 11,000 and 9300 C

Changes in the bathymetry and volume of glacial Lake Agassiz between 9200 and 7700 C 14 yr B.P.

Changes in the bathymetry and volume of glacial Lake Agassiz between 9200 and 7700 C 14 yr B.P.
Bathymetry ; Holocene ; Lake ; Lake level ; Model ; North America ; Palaeogeography ; Palaeohydrology ; Proglacial lake
Computer reconstructions of the bathymetry of the lake were used to quantify variations in the size and form of Lake Agassiz during its final 2 phases (the Nipigon and Ojibway phases). The estimates of Lake Agassiz volumes and releases presented
here provide a quantitative basis for evaluating the impact that Lake Agassiz may have had on North America and on the oceans into which it flowed.

Shoreline forms and deposits in Gallocanta Lake (NE Spain)

Shoreline forms and deposits in Gallocanta Lake (NE Spain)
Climatic variation ; Lacustrine sediment ; Lake ; Lake level ; Quaternary ; Semi-arid area ; Shoreline ; Spain ; Zaragoza
This study attempts to deduce the present and past shoreline dynamics of a small shallow lake. Gallocanta Lake is located in the central Iberian Chain, NE Spain, within a typically Mediterranean semi-arid region.

History of the Puula Lake Complex, Central Finland, and shifts in its outlet

History of the Puula Lake Complex, Central Finland, and shifts in its outlet
C 14 dating ; Deglaciation ; Finland ; Lake ; Lake level ; Palaeo-environment ; Palynology ; Quaternary ; Shoreline
Events associated with shifts in the outlet of a complex of large lakes in Central Finland are studied by means of levellings of ancient shorelines, trend surface analysis, pollen anallysis and radiocarbon dating. This paper determines how and when
the shifts in outlet occurred and what other changes in the lake and river system have taken place during postglacial times. Attention is also paid to the deglaciation of the lake complex and its isolation from the Baltic basin.

The use of total lake-surface area as an indicator of climatic change : examples from the Lahontan Basin

The use of total lake-surface area as an indicator of climatic change : examples from the Lahontan Basin
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 (Lake Lahontan) 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.

Use of soil chronosequences for testing the existence of high-water-level lakes in the McMurdo Dry Valleys, Antarctica

Use of soil chronosequences for testing the existence of high-water-level lakes in the McMurdo Dry Valleys, Antarctica
Antarctica ; Chronosequence ; Holocene ; Lake ; Lake level ; Palaeo-environment ; Polar region ; Soil ; Soil properties ; Statistics
The AA. utilize field observations and data collected from 190 pedons from Wright and Taylor Valleys to search for evidence of high-water-level lakes proposed to have existed during the last Glacial Maximum and early Holocene in the McMurdo Dry
Valleys. The results cast doubt as to whether high-level lakes existed in the McMurdo Dry Valley as recently as the early Holocene. An alternative explanation is that the former lakes had no effects on soils other than depositing deltas with cyanobacteria

Pollen analysis of a Late-Glacial and Holocene sediment core from Mono Lake, Mono County, California

Pollen analysis of a Late-Glacial and Holocene sediment core from Mono Lake, Mono County, California
C 14 dating ; California ; Climatic variation ; Holocene ; Lake level ; Lateglacial ; Palaeo-environment ; Palynology ; Pollen diagram ; Quaternary ; Tephrochronology ; United States of America
Pollen analysis of a 752-cm core from Mono Lake, California, indicates generally high lake levels 11,600-7000 C 14 yr B.P., moderate lake levels until ca. 4000 C 14 yr B.P., and fluctuating levels to the present. Drying events, with lake levels near

Holocene fluctuations of a meromictic lake in southern British Columbia

Holocene fluctuations of a meromictic lake in southern British Columbia
British Columbia ; C 14 dating ; Canada ; Climatic variation ; Holocene ; Lacustrine sedimentation ; Lake ; Lake level ; Palaeoclimatology ; Palaeogeography ; Precipitation ; Salt lake ; Semi-arid area ; Stratigraphy ; Tephrochronology
The AA. describe the stratigraphy of a 5.45-m-long sediment core from Mahoney Lake, a meromictic lake in southern British Columbia. Using changes in sediment alone, the AA. infer changes in lake levels from which they deduce changes in climate
. They infer many sharp oscillations in lake level, and they ascribe these to climate fluctuations throughout the Holocene.

Lake levels since about 40,000 years ago at Lake Chalco, near Mexico city

Lake levels since about 40,000 years ago at Lake Chalco, near Mexico city
C 14 dating ; Diatom ; Holocene ; Lacustrine sediment ; Lake ; Lake level ; Magnetic susceptibility ; Mexico ; Mexico City ; Palaeo-environment ; Pleistocene ; Quaternary ; Volcanism
The AA. present a paleolimnological record from the central part of Lake Chalco (diatoms, magnetic susceptibility, organic content, C 14 ages of sediments). This record, spanning at least 40,000 yr, offers a more detailed interpretation of the last
-glacial and post-glacial environmental history of this lake. The AA. also use recent volcanological findings to explore how volcanic activity may have affected the lake's history.

New evidence for an extended occupation of the Provo shoreline and implications for regional climate change, Pleistocene Lake Bonneville, Utah, USA

New evidence for an extended occupation of the Provo shoreline and implications for regional climate change, Pleistocene Lake Bonneville, Utah, USA
C 14 dating ; Climatic variation ; Holocene ; Lake level ; Palaeo-environment ; Palaeolake ; Pleistocene ; Shoreline ; United States of America ; Utah
Lake Bonneville was a climatically sensitive, closed-basin lake that occupied the eastern Great Basin during the late Pleistocene. Radiocarbon data from this and other studies suggest that the lake oscillated at or near the Provo level much longer
than depicted by current models of lake level change. Radiocarbon data also suggest that the lake dropped from threshold control much more rapidly than previously supposed. These revisions to the Lake Bonneville hydrograph, coupled with independent

Aeolian processes on Turawskie Lake (Silesia Lowland, Southwestern Poland) : a field experiment

Aeolian processes on Turawskie Lake (Silesia Lowland, Southwestern Poland) : a field experiment
Eolian deflation ; Eolian features ; Lacustrine sediment ; Lake ; Lake level ; Palaeogeography ; Poland
Turawskie Lake is a shallow reservoir characterized by a wide sandy littoral zone and large yearly water-level fluctuations. Semi-annual periods of low water level (July-December) result in emergence of broad sandy beaches that are subjected

Chronology and paleohydrology of Late Quaternary high lake levels in the Manyara Basin (Tanzania) from isotopic data (18O, 13C, 14C, Th/U) on fossil stromatolites

Chronology and paleohydrology of Late Quaternary high lake levels in the Manyara Basin (Tanzania) from isotopic data (18O, 13C, 14C, Th/U) on fossil stromatolites
Dating ; Isotope ; Lake level ; Palaeogeography ; Palaeohydrology ; Quaternary ; Tanzania
In this article, new isotopic data on the hydrology and paleohydrology of the Lake Manyara basin are presented. They complement previous studies on lakes Natron and Magadi, to the north, and provide additional information on late Pleistocene

Lake Manly(?) shorelines in the Eastern Mojave Desert, California

Lake Manly(?) shorelines in the Eastern Mojave Desert, California
California ; Desert ; Lake level ; Palaeo-environment ; Palaeolake ; Pleistocene ; Pluvial ; Quaternary ; Tectonics ; United States of America
During pluvial periods of the late Quaternary, Death Valley was occupied by a lake, called Lake Manly. The most prominent shoreline of this lake is that of the Blackwelder stand, 90 m above sea level. The Mesquite Spring and Salt Spring Hills

Lake evolution during the last 3 000 years in China and its implications for environmental change

Lake evolution during the last 3 000 years in China and its implications for environmental change
China ; Climatic variation ; Historical geography ; Holocene ; Human impact ; Lake ; Lake level ; Palaeo-environment ; Quaternary ; Sea level
This paper, a companion to a previous one on lake evolution in China during the past 30,000 yr based on geological data, focuses on lake evolution over the past 3 000 yr, based on historical sources, and its possible implications for environmental

A 35,000 year vegetation and climate history from Potato Lake, Mogollon Rim, Arizona

A 35,000 year vegetation and climate history from Potato Lake, Mogollon Rim, Arizona
Arizona ; Lake level ; Palaeo-ecology ; Palaeo-environment ; Palaeobotany ; Palaeoclimate ; Palaeozoology ; Palynology ; Quaternary ; United States
and/or wet mid-Wisconsin, and a cold and/or wet late-Wisconsin climate for much of the Southwest. Potato Lake was almost completely dry during the mid-Holocene, but lake levels increased to near modern conditions by ca. 3000 yr B.P.
A new record from Potato Lake, central Arizona, details vegetation and climate changes since the mid-Wisconsin for the southern Colorado Plateau. Climatic estimates presented here are consistent with other lines of evidence suggesting a cool

Short-duration Holocene lakes in the Mojave river drainage basin, southern California

Short-duration Holocene lakes in the Mojave river drainage basin, southern California
California ; Climatic variation ; Holocene ; Lake level ; Paleo-environment ; Quaternary ; Sedimentology ; Stratigraphy ; United States
Discusses evidence of middle to late Holocene lake-level fluctuations recorded in the terminal basins of the Mojave River. Presents stratigraphic and sedimentologic evidence of the occurrence of shallow, short-duration, middle to late Holocene lakes
in the terminal playas of the Mojave River in southern California. A possible cause for these short-term wet climatic episodes, as recorded by historic and Holocene lakes is proposed.

Environmental geological research in the Lake Balaton region

Environmental geological research in the Lake Balaton region
C 14 dating ; Eutrophication ; Holocene ; Human impact ; Hungary ; Lacustrine sediment ; Lake ; Lake level ; Palaeo-ecology ; Pollution ; Quaternary ; Recreation area ; Stratigraphy
. In the Holocene increasing temperature and precipitation brought about a progressive rise in lake level.
The research was focused mainly on surveying lake deposits, as well as the morphology and structure of the Pre-Quaternary lake deposits and the morphology and structure of the Pre-Quaternary basement of Lake Balaton. Paleontological investigations
(pollen, diatoms, ostracods) in the 4 subbasins of the lake allowed the reconstruction of the ecological history of the area as well providing detailed stratigraphic information. Radiocarbon dating of peat helps to date the beginning of lake formation

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