natural magnetic sand
Although the presence of haematite cannot be discerned from the high‐temperature magnetization curves due to its inherently weak magnetism, the fact that this north‐to‐south magnetic trend corresponds with an increase in the degree of soil and sand reddening suggests haematite is likely to form the dominant antiferromagnetic phase. More recently, Barron and Torrent , Torrent et al. Geophysics, Mathematical In some cases the interpretation of high‐temperature behavior is complicated by the presence of organic matter which, upon combustion, creates conditions conducive for the formation of new mineral phases [Hanesch et al., 2006]. All rights reserved. The main aims were to document spatial variations in magnetic properties, explore their possible links to climatic gradients and their likely basis, and thereby help to differentiate potential sources for Sahara/Sahel‐derived dusts. The sample transect is mainly underlain by Eocene limestone, Quaternary playa deposits and upper Cretaceous carbonate rocks [Said, 1990; Schlüter, 2006]. This material was then separated by the pipette method [Walden and Slattery, 1993] into seven particle‐size fractions; <2 μm; 2–4 μm; 4–8 μm; 8–16 μm; 16–32 μm; 32–63 μm; and >63 μm, based on the settling velocities in water according to the scales proposed by Folk . The high‐field (800 mT) magnetization behavior of samples over the temperature range 40–700°C, at a heating rate of 30°C min−1, was measured using a Curie Balance and Magnetic Measurements Variable Field Translation Balance (VFTB). Arizona Mined. All remanences were measured using a Molspin spinner magnetometer with a noise level of ∼0.1 × 10−8 Am2. These studies, coupled with the skill shown by magnetic measurements in discriminating the seasonal sources of dust in the Barbados [Oldfield et al., 1985a] point to the possibility of using a similar approach to link magnetic properties to climatic zones in North Africa, thereby taking a first step toward discriminating dust sources in the region on the basis of their magnetic properties. Magnetic analyses of soils from the Wind River Range, Wyoming, constrain rates and pathways of magnetic enhancement for soils from semiarid climates, 10.1175/1520‐0442(1999)012<0829:RTCSTC>2.0.CO;2, Research Spotlight—Modeling the Cascading Infrastructure Impacts of Climate Change, 4 samples from northern Niger (17°50′N to 22°N), 4 samples from southern Niger (14°N to 15°50′N), 5 samples from northern and central Benin (9°50′N to 12°N), 4 samples from southern Benin and Togo (6°N to 6°50′N). $9.35 shipping. $18.75. For example, New Zealand and Iceland have impressive stretches of black sands. Characterizing magnetic mineral assemblages of surface sediments from major Asian dust sources and implications for the Chinese loess magnetism. It is important to note that the envelope of values within which the North African samples fall includes samples from locations as contrasted as the English lake District and the Chinese Loess Plateau, thus confirming the extent to which the properties used in the plot reflect magnetic components that are largely independent of parent material.
Building Code For Concrete Steps, Air Strike Villainous, The Magic School Bus Rides Again Theme Song, 3d Lighting Reference, Elijah Fasted 40 Days, Is Knaphill A Nice Place To Live, Antwaun Woods Net Worth, Vincent Herbert 2020,