The effect of Aeolian accessions on soil development on granitic-rocks in south eastern Australia. II. Oxygen-isotope, mineralogical and geochemical evidence for Aeolian deposition

Soil Research ◽  
1988 ◽  
Vol 26 (1) ◽  
pp. 17 ◽  
Author(s):  
CJ Chartres ◽  
AR Chivas ◽  
PH Walker
Keyword(s):  
Oxygen Isotope ◽  
Soil Formation ◽  
Fine Sand ◽  
Granitic Rocks ◽  
X Ray Diffraction ◽  
Elemental Ratios ◽  
Aeolian Deposits ◽  
Eastern Australia ◽  
Mineral Data ◽  
Quartz Grains

Oxygen-isotope abundance in quartz grains, total chemical analyses and clay mineral data are used to identify aeolian deposits in four soil profiles developed on granitic rocks. Results indicate that quartz fractions derived from I-type granitic rocks have �18O values less than 10.7%, whereas fine sand-sized (50-31 �m) quartz separates from the same soils have �18O values of > 11.6�. Similar, but less marked, differences were observed in a soil on an S-type granitic rock, suggesting that addition of aeolian material to all the soils investigated has been an important process of soil formation. X-ray diffraction data indicate the presence of decreasing proportions of clay mica h the soils with increasing distance from probable sources of aeolianites in the Riverine Plain, raising the possibility that clay mica, along with other clay minerals and clay-size quartz, may have been also deposited by wind in the soils. Titanium/zirconium elemental ratios are less useful indicators of aeolian accession because of complications arising from the weathering of biotite in the underlying granitic rocks. Probable losses of yttrium from the soils also appear to result from weathering of materials derived from the granitic rocks, although some data indicate that zirconium/yttrium ratios for the 50-2 �m fractions may also be indicative of aeolian accession.

The effect of Aeolian accessions on soil development on granitic-rocks in south eastern Australia. III. Micromorphological and geochemical evidence of weathering and soil development

Soil Research ◽  
1988 ◽  
Vol 26 (1) ◽  
pp. 33 ◽  
Author(s):  
CJ Chartres ◽  
PH Walker
Keyword(s):  
Fine Sand ◽  
Soil Development ◽  
Granitic Rocks ◽  
Soil Profiles ◽  
The West ◽  
Parent Materials ◽  
Podzolic Soils ◽  
Swelling Clays ◽  
Eastern Australia ◽  
Red Earth

Micromorphological, mineralogical and chemical data show that clay illuviatidn, clay decomposition and strong weathering of biotite and feldspars to clay mineral$ have all been significant processes of soil development in three red podzolic soils and one red earth. Decomposition of biotite and illuviation of swelling clays into fissures in the saprolite and C horizons appear to have aided the physical fragmentation of the granitic parent materials. Disruption of illuvial features by faunal activity and shrink-swell processes in the upper B horizons accentuate apparent illuvial clay maxima in the B3 and C horizons. Low clay contents in the A horizons of the red podzolic soils examined result from ehviation and clay decomposition, whereas the higher fine sand contents of these horizons result, in part, from the deposition of aeolian transported materials. Substantial aeolian deposition at another site has led to the development of a red earth. The deposition of greater amounts of aeolian material to the soils to the west of Canberra has led to the development of complex, polycyolic soil profiles in comparison to the profiles investigated towards the coast.

scholarly journals Ore Genesis of the Takatori Tungsten–Quartz Vein Deposit, Japan: Chemical and Isotopic Evidence

Minerals ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 765
Author(s):  
Yuichi Morishita ◽  
Yoshiro Nishio
Keyword(s):  
Oxygen Isotope ◽  
Early Stage ◽  
Isotope Ratios ◽  
Equilibrium Temperature ◽  
Granitic Rocks ◽  
Granitic Magma ◽  
Lithium Isotope ◽  
Vein Deposit ◽  
Pressure Independent ◽  
Isotope Equilibrium

The Takatori hypothermal tin–tungsten vein deposit is composed of wolframite-bearing quartz veins with minor cassiterite, chalcopyrite, pyrite, and lithium-bearing muscovite and sericite. Several wolframite rims show replacement textures, which are assumed to form by iron replacement with manganese postdating the wolframite precipitation. Lithium isotope ratios (δ7Li) of Li-bearing muscovite from the Takatori veins range from −3.1‰ to −2.1‰, and such Li-bearing muscovites are proven to occur at the early stage of mineralization. Fine-grained sericite with lower Li content shows relatively higher δ7Li values, and might have precipitated after the main ore forming event. The maximum oxygen isotope equilibrium temperature of quartz–muscovite pairs is 460 °C, and it is inferred that the fluids might be in equilibrium with ilmenite series granitic rocks. Oxygen isotope ratios (δ18O) of the Takatori ore-forming fluid range from +10‰ to +8‰. The δ18O values of the fluid decreased with decreasing temperature probably because the fluid was mixed with surrounding pore water and meteoric water. The formation pressure for the Takatori deposit is calculated to be 160 MPa on the basis of the difference between the pressure-independent oxygen isotope equilibrium temperature and pressure-dependent homogenization fluid inclusions temperature. The ore-formation depth is calculated to be around 6 km. These lines of evidence suggest that a granitic magma beneath the deposit played a crucial role in the Takatori deposit formation.

scholarly journals The properties of river alluviums of the Upper-Dniester alluvial plain

2017 ◽  
pp. 293-303
Author(s):  
Khrystyna Perets ◽  
Oksana Vovk ◽  
Oleh Orlov ◽  
Olena Lutsyshyn
Keyword(s):  
Granulometric Composition ◽  
Alluvial Soil ◽  
Chemical Properties ◽  
Soil Formation ◽  
Hydrological Regime ◽  
Clay Content ◽  
Fine Sand ◽  
Alluvial Plain ◽  
Alluvial Soils ◽  
Floodplain Soil

Alluvial soil formation is a dynamic process, the main prerequisite of which is the regular, periodic flooding of the river floodplain with flood waters, which are enriched with multidispersed organic and mineral particles. During the last century, about 80 % of territory of the Upper-Dniester alluvial plain was transformed by means of hydrotechnical construction: waterproof dams and drainage channels have broken the wide river floodplains into isolated fragments, making impossible the free flow of flood waters, enriched with silt. The results of the study of stratification patterns of the river silt in the riverbed floodplain, depending on the flow velocity, granulometric composition, physical and chemical properties, given its role in the floodplain soil formation are given. The granulometric composition of the Dniester River silt changes downstream from the sandy to the heavy-loamy; In the floodplains of the Stryj and Svicha rivers medium- and heavy-loamy deposits are postponed, respectively. In the upper part of the Upper- Dniester alluvial plain (Chaikovichi 1, 2) accumulates a silt with predominance of the medium and fine sand fraction, which forms a good filtration ability of soils, whereas downstream the physical clay content increases (up to 47.2 %), which makes the river silt an important source of mineral nutrition of plants. The domination (over 40 %)in silt granulometric composition the rough dust fraction (Ustia 1, Zalisky 1) contributes to the improvement of the water-physical properties of alluvial soils and provides optimal conditions for the biota functioning. For the investigated river alluviums an alkaline reaction of the extract (pH (H2O) = 7,44–8,03) and low content of humus (0,54–3,80 %) are characteristic. The amount of nitrogen in the silt varies within 1,47–18,20 mg/100 g of soil. The river alluviums of the Upper-Dniester alluvial plain are an active factor in floodplain soil formation, since it optimizes the water-physical and physical-chemical properties of alluvial soils. But the influence area of silt on the soilsis sharply reduced and is limited only to the space in front of the dams. In the soils outside the dam, to which no fresh alluvial material comes, the hydrological regime is rebuilt and properties change substantially, up to the loss of their typological alluvial features. Key words: river alluviums, silt, floodplain, the Upper-Dniester alluvial plain, alluvial soils, hydrotechnical fragmentation.

scholarly journals MICROMORPHOLOGY AND PEDOGENESIS OF MOUNTAINOUS INCEPTISOLS IN THE MANTIQUEIRA RANGE (MG)

2015 ◽  
Vol 39 (5) ◽  
pp. 455-462 ◽  
Author(s):  
Leandro Campos Pinto ◽  
Yuri Lopes Zinn ◽  
Carlos Rogério de Mello ◽  
Phillip Ray Owens ◽  
Lloyd Darrell Norton ◽  
...  
Keyword(s):  
Soil Formation ◽  
Intermediate Stage ◽  
Mineral Weathering ◽  
Southeastern Brazil ◽  
Native Forest ◽  
Subtropical Climate ◽  
Formation Processes ◽  
Severe Reduction ◽  
Mineral Alteration ◽  
Quartz Grains

ABSTRACTUnderstanding soil formation processes across different landscapes is needed to predict how soil properties will respond to land use change. This study aimed to characterize mountainous Inceptisols (Cambisols) under high altitude subtropical climate in southeastern Brazil, by soil physical, chemical and micromorphological analyses, under native forest and pasture. The soil under pasture had a greater bulk density than under forest, resulting in a severe reduction of macroporosity. At two depths, coarse quartz grains are angular, suggesting absence of transportational processes, thus confirming an autochthonous pedogenesis from the underlying gneissic rock. Most feldspars were weathered beyond recognition, but mineral alteration was commonly seen across cleavage plans and edges of micas. The micromorphological results suggest an intermediate stage of mineral weathering and soil development, which is in accordance with properties expected to be found in Inceptisols.

Weathering and soil formation on dolerite in Tasmania with particular reference to several trace elements

Soil Research ◽  
1963 ◽  
Vol 1 (1) ◽  
pp. 74 ◽  
Author(s):  
KG Tiller
Keyword(s):  
Trace Elements ◽  
Soil Formation ◽  
Fine Sand ◽  
Climatic Conditions ◽  
Parent Material ◽  
Soil Profiles ◽  
Podzolic Soils ◽  
Nickel Copper ◽  
Soil Groups

The mineralogy and chemistry of weathering and soil formation have been studied at 17 widely separated sites with contrasting climatic conditions on comparatively uniform dolerite in Tasmania. The clay and fine sand mineralogy of the soils has been related to their degree of weathering. These studies have shown large chemical and mineralogical changes accompanying the initial stages of weathering in some krasnozem soils. The reorganization of cobalt, zirconium, nickel, copper, molybdenum, manganese, and zinc during genesis of four soil groups has been considered in terms of the factors involved. Some of these results indicate that the clay horizon of the podzolic soils has probably been formed by weathering in situ. Seasonal waterlogging in certain horizons has strongly mfluenced the chemistry and mineralogy of weathering in many of these soils. This study has shown that the composition of the parent material has only influenced the geochemistry of trace elements in less weathered soils and that pedogenic factors assumed greater significance as the soils became more strongly weathered. Geomorphic processes had a marked influence on the geochemistry of some soils by the truncation of mature soil profiles.

The nature and possible origins of soluble salts in deeply weathered landscapes of eastern Australia

Soil Research ◽  
1979 ◽  
Vol 17 (2) ◽  
pp. 197 ◽  
Author(s):  
RH Gunn ◽  
DP Richardson
Keyword(s):  
Sedimentary Rocks ◽  
Granitic Rocks ◽  
Soluble Salts ◽  
Sea Salts ◽  
Soluble Ions ◽  
Late Tertiary ◽  
Eastern Australia ◽  
Salt Affected Soils ◽  
Hydrologic Conditions

Extensive areas of salt-affected soils in eastern Australia occur on the exposed lower zones of lateritic profiles or in derived materials. Analyses of 96 samples of mottled and pallid zones collected in this study show that they generally contain appreciable soluble salts, predominantly sodium chloride, particularly where they developed in argillaceous sedimentary rocks which underlie about two-thirds of the area, and in some granitic rocks. Analyses of 96 samples of unweathered rocks indicate that some contain moderate to appreciable quantities of sodium and chloride, and it is suggested that these and other soluble ions accumulated in the lower zones as a result of deep weathering in the Mid-Tertiary. Atmospheric accessions of sea salts in rain or dry fallout at present rates account partly for the occurrence of salt-affected soil landscapes in some coastal areas but are unlikely sources of salts far inland. Soils formed in situ on weathered basalt, argillaceous sedimentary and granitic rocks which have been exposed at the surface since the Late Tertiary are not salt-affected, because climatic, topographic and hydrologic conditions are different from those of the Mid-Tertiary and only small volumes of rock are involved.

Paleotopography controls weathering of Cambrian-age profiles beneath the Great Unconformity, St. Francois Mountains, SE Missouri, U.S.A.

2020 ◽  
Vol 90 (6) ◽  
pp. 629-650
Author(s):  
Katie J. Pevehouse ◽  
Dustin E. Sweet ◽  
Branimir Šegvić ◽  
Charles C. Monson ◽  
Giovanni Zanoni ◽  
...  
Keyword(s):  
Fluid Flow ◽  
Spatial Relationship ◽  
Soil Formation ◽  
Sedimentary Basins ◽  
X Ray Diffraction ◽  
Soil Thickness ◽  
Subaerial Exposure ◽  
Soil Creep ◽  
Paleozoic Sedimentary Rock ◽  
Fluid Alteration

ABSTRACT Precambrian (1.4 to 1.5 Ga) granite and rhyolite in the St. Francois Mountains at the northeast corner of the Ozark Plateau in Missouri has been altered down to a depth up to 8 meters below the Great Unconformity (the contact between Paleozoic sedimentary rock and underlying Precambrian). Petrographic, geochemical, and mineralogic data indicate that at least two events generated this alteration: 1) surficial weathering due to subaerial exposure of the granite before Cambrian burial—this material is preserved as a paleosol; and 2) alteration due to reaction with basinal fluids channeled along the unconformity from nearby sedimentary basins long after burial by Paleozoic strata. To assess the variation between surficial weathering and basinal fluid alteration, we measured and sampled for petrologic, geochemical, and mineralogic data in the rock at and just below the Great Unconformity at three paleoelevations. Whole-rock geochemical oxide and X-ray diffraction data indicate that K-metasomatism and highly crystalline illite occurred in each profile. The K increase reflects crystallization of authigenic feldspar and illite from basinal fluids that were channeled along the Great Unconformity during younger Paleozoic fluid-flow events. Each profile also exhibits an upward increase in altered feldspar crystals and highly crystalline kaolinite, and an upward decrease in Ca and Na. Such changes reflect soil formation due to reaction with meteoric water before Cambrian burial, indicating that the altered granite was a paleosol before Paleozoic basinal fluid-flow events. Notably, the paleosol at the highest paleoelevation displays the least amount of paleoweathering and the paleosol at the lowest displays the greatest amount of paleoweathering. These results demonstrate that not only can characteristics of the paleosol just below the Great Unconformity be recognized in the St. Francois Mountains, despite subsequent alteration, but also it is possible to detect variations in soil thickness that were controlled by slope steepness and, therefore, water availability and/or soil creep or failure. This spatial relationship is compatible with studies of modern soils which indicate that soil character varies with position on a slope.

Hydrolysis of ceramic materials: neoformation or rehydroxylation of clay minerals. Oxygen stable isotope analysis

Clay Minerals ◽  
2002 ◽  
Vol 37 (2) ◽  
pp. 345-349 ◽  
Author(s):  
R. Nuñez ◽  
J . Capel ◽  
E. Reyes ◽  
A. Delgado
Keyword(s):  
Oxygen Isotope ◽  
Clay Minerals ◽  
Isotope Composition ◽  
Isotope Analysis ◽  
Size Fraction ◽  
Ceramic Materials ◽  
X Ray Diffraction ◽  
X Ray ◽  
Fired Bricks ◽  
Oxygen Stable Isotope

AbstractHand-made bricks were manufactured from natural sediments by firing at 700°C and 800°C after which they were hydrothermally altered at 150°C in a high-pressure reactor for 1200 h. Sediments and fired pieces were studied by X-ray diffraction. The <2 μm size-fraction of fired and hydrolysed samples were also studied by X-ray diffraction and oxygen isotope analysis. The oxygen isotope composition of the samples became depleted in 18O by alteration. Our results are consistent with a process of hydration and hydroxylation of the partially destroyed clay minerals in the fired bricks. The work is relevant to understanding the origins and alteration processes in old ceramic materials.

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