Pedogenesis and tephrochronology of loess derived soils, Hinton, Alberta

1980 ◽  
Vol 17 (1) ◽  
pp. 52-59 ◽  
Author(s):  
J. Dumanski ◽  
S. Pawluk ◽  
C. G. Vucetich ◽  
J. D. Lindsay
Keyword(s):  
Climatic Change ◽  
Volcanic Ash ◽  
Soil Formation ◽  
Gradual Change ◽  
The Holocene ◽  
Loess Deposition

The loess derived soils of the Hinton district provide a record of soil formation for the entire postglacial period. Loess originates from the shorelines of Brûlé Lake and from the sandbars and braided channels of the Athabasca River.The geochronology of the loess, as established through the study of paleosols and volcanic ash beds, indicates that loess deposition was continual but irregular. Soil formation occurred contemporaneously with loess deposition, and varying soil morphologies were attributed to differing local rates of loess accumulation. There was no evidence for marked climatic change during the Holocene in the study area, but increased loess supply after 4000 years BP may reflect gradual change.

scholarly journals Holocene loess deposition and soil formation as competing processes, Matanuska Valley, Southern Alaska

2004 ◽  
Vol 61 (3) ◽  
pp. 265-276 ◽  
Author(s):  
Daniel R. Muhs ◽  
John P. McGeehin ◽  
Jossh Beann ◽  
Eric Fisher
Keyword(s):  
Soil Formation ◽  
Source Surface ◽  
Dust Deposition ◽  
Time Intervals ◽  
Fine Silt ◽  
Silt Content ◽  
Quaternary Climate ◽  
Outwash Plain ◽  
Loess Deposition ◽  
Strong Winds

Although loess–paleosol sequences are among the most important records of Quaternary climate change and past dust deposition cycles, few modern examples of such sedimentation systems have been studied. Stratigraphic studies and 22 new accelerator mass spectrometry radiocarbon ages from the Matanuska Valley in southern Alaska show that loess deposition there began sometime after ∼6500 14C yr B.P. and has continued to the present. The silts are produced through grinding by the Matanuska and Knik glaciers, deposited as outwash, entrained by strong winds, and redeposited as loess. Over a downwind distance of ∼40 km, loess thickness, sand content, and sand-plus-coarse-silt content decrease, whereas fine-silt content increases. Loess deposition was episodic, as shown by the presence of paleosols, at distances >10 km from the outwash plain loess source. Stratigraphic complexity is at a maximum (i.e. the greatest number of loesses and paleosols) at intermediate (10–25 km) distances from the loess source. Surface soils increase in degree of development with distance downwind from the source, where sedimentation rates are lower. Proximal soils are Entisols or Inceptisols, whereas distal soils are Spodosols. Ratios of mobile CaO, K2O, and Fe2O3 to immobile TiO2 show decreases in surface horizons with distance from the source. Thus, as in China, where loess deposition also takes place today, eolian sedimentation and soil formation are competing processes. Study of loess and paleosols in southern Alaska shows that particle size can vary over short distances, loess deposition can be episodic over limited time intervals, and soils developed in stabilized loess can show considerable variability under the same vegetation.

scholarly journals Radiocarbon Dating of Buried Holocene Soils in Siberia

Radiocarbon ◽  
2002 ◽  
Vol 44 (1) ◽  
pp. 113-122 ◽  
Author(s):  
Lyubov A Orlova ◽  
Valentina S Zykina
Keyword(s):  
Radiocarbon Dating ◽  
Climate Changes ◽  
Soil Formation ◽  
Forest Steppe ◽  
Buried Soils ◽  
Forest Environment ◽  
The Holocene ◽  
Holocene Climatic Optimum ◽  
Time Period ◽  
Two Stages

We have constructed a detailed chronological description of soil formation and its environments with data obtained on radiocarbon ages, palynology, and pedology of the Holocene buried soils in the forest steppe of western and central Siberia. We studied a number of Holocene sections, which were located in different geomorphic situations. Radiocarbon dating of materials from several soil horizons, including soil organic matter (SOM), wood, peat, charcoal, and carbonates, revealed three climatic periods and five stages of soil formation in the second part of the Holocene. 14C ages of approximately 6355 BP, 6020 BP, and 5930 BP showed that the longest and most active stage is associated with the Holocene Climatic Optimum, when dark-grey soils were formed in the forest environment. The conditions of birch forest steppe favored formation of chernozem and associated meadow-chernozem and meadow soils. Subboreal time includes two stages of soil formation corresponding to lake regressions, which were less intense than those of the Holocene Optimum. The soils of that time are chernozem, grassland-chernozem, and saline types, interbedded with thin peat layers 14C dated to around 4555 B P, 4240 BP and 3480 BP, and 3170 B P. Subatlantic time includes two poorly developed hydromorphic paleosols formed within inshore parts of lakes and chernozem-type automorphic paleosol. The older horizon was formed during approximately 2500–1770 BP, and the younger one during approximately 1640–400 B P. The buried soils of the Subatlantic time period also attest to short episodes of lake regression. The climate changes show an evident trend: in the second part of the Atlantic time period it was warmer and drier than at present, and in the Subboreal and Subatlantic time periods the climate was cool and humid.

Transport Direction of Peoria Loess in Nebraska and Implications for Loess Sources on the Central Great Plains

2001 ◽  
Vol 56 (1) ◽  
pp. 79-86 ◽  
Author(s):  
Joseph A. Mason
Keyword(s):  
Climatic Change ◽  
Great Plains ◽  
Source Region ◽  
Ice Sheet ◽  
Laurentide Ice Sheet ◽  
Secondary Sources ◽  
River Floodplains ◽  
Transport Direction ◽  
Loess Deposition ◽  
Ice Sheet Dynamics

AbstractIn the midwestern United States, large rivers draining the Laurentide Ice Sheet (LIS) were the most important sources of Peoria Loess, deposited during the last glaciation. Loess deposition near those rivers may have responded primarily to ice-sheet dynamics rather than direct effects of climatic change. In contrast, it has been proposed that thick Peoria Loess on the central Great Plains was derived mainly from unglaciated landscapes northwest of the main loess deposits. In this study, transport directions inferred from more than 600 measurements of Peoria Loess thickness in Nebraska are used to test the hypothesis that much of the Peoria Loess on the Great Plains is nonglaciogenic. A strong northwest to southeast thickness trend indicates that most Peoria Loess in Nebraska was transported from one or more unglaciated northwestern source areas rather than from glacially influenced river floodplains. The Missouri River (draining the LIS), the Platte River (draining alpine glaciers), and the Elkhorn River (unglaciated basin) were secondary sources. Their contribution is not detectable beyond a distance of 40–60 km. Peoria Loess deposition on the central Great Plains was largely a direct response to climatic change in the unglaciated source region.

scholarly journals A late Quaternary record of eolian silt deposition in a maar lake, St. Michael Island, western Alaska

2003 ◽  
Vol 60 (1) ◽  
pp. 110-122 ◽  
Author(s):  
Daniel R. Muhs ◽  
Thomas A. Ager ◽  
Josh Been ◽  
J. Platt Bradbury ◽  
Walter E. Dean
Keyword(s):  
Lake Sediments ◽  
Late Quaternary ◽  
Geochemical Data ◽  
Unexpected Finding ◽  
The Holocene ◽  
Tundra Vegetation ◽  
Shrub Tundra ◽  
Loess Deposition ◽  
Maar Lake ◽  
Glacial Time

AbstractRecent stratigraphic studies in central Alaska have yielded the unexpected finding that there is little evidence for full-glacial (late Wisconsin) loess deposition. Because the loess record of western Alaska is poorly exposed and not well known, we analyzed a core from Zagoskin Lake, a maar lake on St. Michael Island, to determine if a full-glacial eolian record could be found in that region. Particle size and geochemical data indicate that the mineral fraction of the lake sediments is not derived from the local basalt and is probably eolian. Silt deposition took place from at least the latter part of the mid-Wisconsin interstadial period through the Holocene, based on radiocarbon dating. Based on the locations of likely loess sources, eolian silt in western Alaska was probably deflated by northeasterly winds from glaciofluvial sediments. If last-glacial winds that deposited loess were indeed from the northeast, this reconstruction is in conflict with a model-derived reconstruction of paleowinds in Alaska. Mass accumulation rates in Zagoskin Lake were higher during the Pleistocene than during the Holocene. In addition, more eolian sediment is recorded in the lake sediments than as loess on the adjacent landscape. The thinner loess record on land may be due to the sparse, herb tundra vegetation that dominated the landscape in full-glacial time. Herb tundra would have been an inefficient loess trap compared to forest or even shrub tundra due to its low roughness height. The lack of abundant, full-glacial, eolian silt deposition in the loess stratigraphic record of central Alaska may be due, therefore, to a mimimal ability of the landscape to trap loess, rather than a lack of available eolian sediment.

Soil record of the Holocene paleofires at the north of European Russia

2020 ◽  
Author(s):  
Nikita Mergelov ◽  
Dmitry Petrov ◽  
Andrey Dolgikh ◽  
Elya Zazovskaya
Keyword(s):  
Kola Peninsula ◽  
Forest Fires ◽  
Soil Formation ◽  
Basic Research ◽  
Isotope Ratio Mass Spectrometry ◽  
Local Scale ◽  
14C Dating ◽  
The Holocene ◽  
Arkhangelsk Region ◽  
The North

<p>Soils and sediments serve as complementary sources of detailed information on paleofires in various ecosystems. Despite the abundance of charcoal material entrapped in soils they remain relatively less studied pyrogenic archives in comparison to the sedimentary paleofire records (e.g. lacustrine and peat deposits), and that is especially the case for the most territory of Russia. We report here on the numerous soil archives of the Holocene forest fires at the Kola Peninsula (66.347°N, 37.948°E) and the north of Arkhangelsk region (64.747°N, 43.387°E) in Russia. Series of buried Podzols (up to ten successive profiles) separated by the distinct charcoal layers were revealed in specific geomorphological traps like the thermokarst depressions inherited from the early stages of moraine sediments formation (Kola Peninsula), as well as in active and paleokarst sinkholes in carbonate and sulfate rocks (Arkhangelsk region). The maximum temporal depth of archives was estimated as 10261±40 cal yr BP for the key site in Arkhangelsk region, with up to 12 major pyrogenic events recorded at the local scale. Soil formation at the inter-pyrogenic stages maintained a uniform direction for at least 10 thousand years and profiles of Podzols were regularly replicated at all the key sites. We employ here a combination of soil morphological hierarchical analysis, study of geomorphological processes leading to the burial of pyrogenic carbon, 14C dating of charcoal and TOC derived from the soil organic matter, carbon and nitrogen isotope ratio mass spectrometry and anthracomass concentrations analysis to extract a set of paleoenvironmental information from these soil archives. The study of complementary pyrogenic archives in the three-component system of the karst landscape (including bottom and slopes of the funnels, as well as the flat elevated areas between them) helped to mitigate overestimation or underestimation of the anthracomass concentration and allowed to acquire a detailed dataset on paleopyrogenic events at the local scale. This study is supported by the Russian Foundation for Basic Research, Project No. 19-29-05238.</p>

Evidence of Stream Response to Holocene Climatic Change in a Small Wisconsin Watershed

1983 ◽  
Vol 19 (1) ◽  
pp. 100-116 ◽  
Author(s):  
Patricia F. McDowell
Keyword(s):  
Simple Model ◽  
Climatic Change ◽  
Climatic Changes ◽  
Soil Development ◽  
Fluvial System ◽  
Alluvial Deposits ◽  
The Holocene ◽  
Fluvial Response ◽  
Stream Response ◽  
The Relationship

AbstractDuring the Holocene, moderate climatic and vegetational changes triggered several episodes of adjustment in the Brush Creek fluvial system. The alluvial chronology includes an episode of erosion at 7800 – 5700 yr B.P. corresponding to the mid-Holocene precipitation minimum and an episode of floodplain construction at 5700 – 5000 yr B.P. corresponding to a rapid increase in precipitation. Holocene climatic changes have influenced the sedimentology of the alluvial deposits and soil development on them. Fluvial adjustment is caused primarily by hydrologic and hydraulic changes related to climatic change, but there is no simple model for fluvial response to climatic change. The relationship between the direction of climatic change and the type of fluvial response is complex.

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