China ; Climatic variation ; Loess ; Magnetic susceptibility ; Oxygen 18 ; Paleoclimatology ; Paleosols ; Quaternary ; Stratigraphy
The origins of the magnetic susceptibility variations of the Chinese loess and paleosols are explored by scanning and transmission electron microscopy of magnetic extracts, and by magnetic modeling of magnetic hysteresis data, to provide quantified
estimates of the major magnetic components. The AA. identify pedogenic formation of magnetite as the major contributor to the loess magnetic record. Matching this record against other paleoclimatic records, they find an high correlation with the standard 18O
record. The Chinese loess sequences record a very high resolution magnetic stratigraphy directly related to changing climate.
Factors affecting the magnetic susceptibility of a loess-soil sequence, Barton County, Kansas, USA
Chronostratigraphie ; Etats-Unis ; Kansas ; Loess ; Paléoclimatologie ; Propriétés du sol ; Pédogenèse ; Sol ; Stratigraphie ; Susceptibilité magnétique
Chronostratigraphy ; Kansas ; Loess ; Magnetic susceptibility ; Palaeoclimatology ; Pedogenesis ; Soil ; Soil properties ; Stratigraphy ; United States of America
To interpret climatic signatures from magnetic susceptibility (MS) in the Barton County loess-soil sequence, the AA. test the influence of particle size and carbonate concentration on magnetic susceptibility. Discussion of the results.
Time dependence of magnetic susceptibility of soil chronosequences on the California coast
California ; Chronoséquence ; Etats-Unis ; Pédogenèse ; Quaternaire ; Sol ; Susceptibilité magnétique
California ; Chronosequence ; Magnetic susceptibility ; Pedogenesis ; Quaternary ; Soil ; United States
The AA. discuss the magnetic mineralogy of a soil chronosequence formed from beach deposits on uplifted marine terraces in California that range in age from 1 700 to 240,000 yr. They compare the data from three chronosequences to show
the relationships between time and selected soil magnetic properties.
The significance of various sediment magnetic mineral fractions for tracing sediment sources in Killimicat Creek
Australie ; Bassin-versant ; Charge solide ; Confluence ; Minéraux lourds ; New South Wales ; Susceptibilité magnétique ; Sédimentologie ; Traceur
Australia ; Confluent ; Heavy minerals ; Magnetic susceptibility ; New South Wales ; Sediment load ; Sedimentology ; Tracer ; Watershed
This paper reports on experiments to measure the relative contributions of the magnetic constituents of sediments. The proportionate contributions of heavy and light mineral components of two different sediment streams delivered to the confluence
in the headwaters of Killimicat Creek, New South Wales, are determined from mineral magnetic measurements. The results show that most of the magnetic mineral component is associated with sediment particles, rather than the discrete heavy mineral component.
Climatic variability ; Drought ; Holocene ; Human occupation ; Lacustrine sediment ; Land use ; Magnetic susceptibility ; Minnesota ; Palaeo-environment ; Palaeoclimate ; Sedimentology ; United States of America
Sediment magnetic properties of a short core from Sharkey Lake record the effects of Euroamerican settlement and climate change over the last 150 yr. The onset of European-style farming led to increase erosion, reflected in high values
of concentration-dependent parameters such as magnetic susceptibility (k), Isothermal Remanent Magnetization (IRM), and Anhysteretic Remanent Magnetization (ARM). High organic productivity in the lake during 1920s to 1940s drought increased the authigenic component
resulting in highly magnetic fine-grained sediment. The effects of dissolution and the superposition of climate and land-use signals complicate the use of recent sediments as modern analogs for sediment magnetic analyses.
This study attempts to quantify post- and pre-1960 soil erosion in a small cultivated basin near Saskatoon, Saskatchewan, Canada, by measuring Cs 137 and magnetic susceptibility distribution with depth. The objective was to see if the differences
in magnetic susceptibility between topsoil and subsoil, and between soils of different slope positions could be used to quantify soil redistribution in a cultivated field.
Magnetic properties of the urban soils in Shanghai and their environmental implications
Chine ; Etude comparée ; Minéraux lourds ; Pollution ; Pollution du sol ; Propriétés du sol ; Shanghai ; Sol ; Sol cultivé ; Sol urbain ; Susceptibilité magnétique
China ; Comparative study ; Cultivated land ; Heavy minerals ; Magnetic susceptibility ; Pollution ; Shanghai ; Soil ; Soil pollution ; Soil properties
To evaluate the feasibility of using magnetic techniques for monitoring soil pollution in Shanghai, magnetic properties and heavy metals in the topsoils in an urban site (Songnan Town) and a less-urbanized agricultural site (Luojing Town) in Baoshan
Arid area ; China ; Climatic change ; Gansu ; Loess ; Magnetic susceptibility ; Mountain ; Palaeo-environment ; Pleistocene ; Semi-arid area
The AA. report their recent magnetic fabric investigation of loess deposition in Shagou section, located at the northeastern Qilian Mountains, the northeastern rim of the Tibetan plateau. On the basis of environmental magnetism data, they indicate
that the variation of anisotropy of magnetic susceptibility (AMS) parameters, especially the foliation (F) and degree of anisotropy (P), might be more sensitive to the environmental change in the arid and semiarid regions than the magnetic susceptibility fluctuation
Magnetic susceptibility of soils in different slope positions in Saskatchewan, Canada
Canada ; Catena ; Chernozem ; Granulométrie ; Luvisol ; Pente de versant ; Propriétés du sol ; Saskatchewan ; Sol ; Susceptibilité magnétique ; Zone froide
Canada ; Catena ; Chernozem ; Cold area ; Grain size distribution ; Magnetic susceptibility ; Saskatchewan ; Slope gradient ; Soil ; Soil properties
The magnetic susceptibility (χ) of soils varies with the slope position due to some factors, such as texture and drainage class. This study attempts to link χ to soil profile characteristics for different landscape positions at two chernozemic sites
Fossil fauna ; Loess ; Magnetic susceptibility ; Mollusca ; Nebraska ; Palaeo-environment ; Palaeoclimatology ; Palaeomagnetism ; Pleistocene ; United States of America
Based on multivariate analysis of mollusk assemblages and magnetic susceptibility of the Eustis section in western Nebraska, the climate of the Peoria loess steppe was relatively mild and, in terms of annual precipitation, relatively moist during
Magnetic enhancement in wildfire-affected soil and its potential for sediment-source ascription
Australie ; Bassin-versant ; Erosion des sols ; Incendie de forêt ; New South Wales ; Propriétés du sol ; Susceptibilité magnétique ; Traceur
Australia ; Forest fire ; Magnetic susceptibility ; New South Wales ; Soil erosion ; Soil properties ; Tracer ; Watershed
The AA. investigate variation in magnetic enhancement of soil by fire in burnt eucalypt forest slopes to explore its potential as a post-fire sediment tracer. The study was undertaken in the Nattai River catchment, 85 km southwest of Sydney, New
Indiana ; Magnetic susceptibility ; Methodology ; Rainfall simulation ; Slope ; Soil erosion ; Tracer ; United States of America ; Water erosion
The aim of this study was to use a magnetic tracer to study spatial variations of soil detachment and deposition on hillslopes under different rainfall intensities and runoff rates and to identify areas where those processes occur. The results allow
Mapping contemporary magnetic mineral concentrations in peat soils using fine-resolution digital terrain data
Cartographie ; England ; Modèle numérique de terrain ; Propriétés du sol ; Ravinement ; Royaume-Uni ; Sol hydromorphe ; Susceptibilité magnétique ; Topographie ; Tourbière ; Yorkshire
Cartography ; Digital elevation model ; England ; Gully erosion ; Hydromorphic soil ; Magnetic susceptibility ; Peat bog ; Soil properties ; Topography ; United Kingdom ; Yorkshire
Recent adavances in the field od digital terrain analysis and the avaibility of fine-resolution digital elevation models means that the relationship between the concentration of magnetic minerals in peat soils and topography can be explored using
quantitative methods. Alport Moor is an ombotrophic peat moorland in the Peak District National Park, UK, where 24 peat cores were collected. Each core was analysed for mass specific magnetic susceptibility. The mapping results demonstrate that the contemporary
concentration of magnetic minerals in the peat soils of Alport Moor is controlled by micro- and local-scale variations in water table position.
A comparison of mineral-magnetic and distributed RUSLE modeling in the assessment of soil loss on a southeastern U.S. cropland
Alabama ; Catena ; Erosion des sols ; Etats-Unis ; Modèle ; Propriétés du sol ; Sol cultivé ; Susceptibilité magnétique
Alabama ; Catena ; Cultivated land ; Magnetic susceptibility ; Model ; Soil erosion ; Soil properties ; United States of America
This study addresses the capacity of rapidly and cheaply acquired mineral-magnetic data to provide detailed spatially distributed assessments of long-term cumulative soil loss from agricultural fields. Model output from a simple distributed
implementation of the Revised Universal Soil Loss Equation (RUSLE) and from a field-data-oriented soil magnetism-based erosion model are compared for a small Alabama (USA) farm lot. RUSLE underpredicted denudation relative to magnetism-model results over upper
Use of mineral magnetic measurements to investigate soil erosion and sediment delivery in a small agricultural catchment in limestone terrain
Alabama ; Bassin-versant ; Bilan sédimentaire ; Cartographie thématique ; Erosion des sols ; Etats-Unis ; Modèle ; Méthodologie ; Pente de versant ; Prévision ; Sol cultivé ; Susceptibilité magnétique
Alabama ; Cultivated land ; Forecast ; Magnetic susceptibility ; Methodology ; Model ; Sediment budget ; Slope gradient ; Soil erosion ; Thematic mapping ; United States of America ; Watershed
In this study, variations in surface magnetism are analyzed to determine patterns of erosion and sedimentation in a small agricultural catchment in northwestern Alabama (USA). Magnetic indicators of erosion are combined with published soil
morphology, Cs-137 and short-term suspended sediment data from this former experimental watershed to evaluate long-term sediment delivery. The results suggest the need for continued refinement of magnetic techniques for purposes of erosion model validation
Building on previous work, the AA. analyzed high-resolution changes in the low-field magnetic susceptibility, pedology, lithology, and pollen content of these late Pleistocene deposits to compare the Vyazivok stratigraphy with better known loess
Apports de la susceptibilité magnétique à l'étude des remplissages des sites préhistoriques. Exemple la grotte des Conques (Vingrau, Pyrénées Orientales)
Archeological site ; Cave ; Climatic variation ; France ; Karst filling ; Languedoc-Roussillon ; Magnetic susceptibility ; Pyrénées-Orientales ; Quaternary ; Stratigraphy
La grotte des Conques à Vingrau est le seul site magdalénien du département des Pyrénées-Orientales à être l'objet d'une fouille scientifique. L'étude de la susceptibilité magnétique permet de mieux comprendre l'histoire et la nature des grains
présence de 3 niveaux de susceptibilité différente.