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R W Payton - One of the best experts on this subject based on the ideXlab platform.
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fragipan formation in argillic brown earths fragiudalfs of the milfield plain north east england ii post devensian developmental processes and the origin of fragipan consistence
European Journal of Soil Science, 1993Co-Authors: R W PaytonAbstract:SUMMARY Pedogenetic processes following a permafrost stage of development in four argillic brown earths with Fragipans (Glossic and Ochreptic Fragiudalfs) are investigated by soil microscopy, including SEM observations of unimpregnated soil material, and by determination of clay mineralogy. Micromorphology of the apparently massive fragipan confirms both the presence of subhorizontal fissures infilled with illuvial deposits separating dense lenticular structures formed by ice-lens growth, and former vertical fissures formed by dessication on freezing with subsequent widening by ice-vein development. The firmness and brittle failure of the Fragipans are attributed to a closely-packed, well-graded matrix of skeleton grains bonded by clay bridges consisting of non-swelling illite and chlorite and to weak interconnection of macrovoids. Weak cementation is rejected as an explanation of fragipan consistence. Sequential stages of particle translocation have been critical to fragipan formation. High bulk density is attributed not only to irregular compression and contraction of the soil matrix under permafrost conditions but also to the infilling of voids by illuvial silt and clay. The full development of the Fragipans has depended on Flandrian clay migration which has contributed to clay-bridge formation, void infilling and localized seasonal impedance of drainage resulting in eluviation of iron oxides, the development of grey polygonal patterning, and processes of degradation at the pan surface leading to glossic features.
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Fragipan formation in argillic brown earths (Fragiudalfs) of the Milfield Plain, north‐east England. III. Micromorphological, SEM and EDXRA studies of fragipan degradation and the development of glossic features
European Journal of Soil Science, 1993Co-Authors: R W PaytonAbstract:SUMMARY The micromorphology of eluvial and glossic areas with weak soi1, strength from the upper fragipan, and the upper parts of grey polygonal zones, in some argillic brown earths (Glossic Fragiudalfs) from north-east England shows unstable void walls stripped of clay with remnants of ferri-argillans, pale grey grainy clay coatings and darker grainy coatings. These occur alongside loose surface residues of skeleton grains and thin grey fine silt coatings of quartz and muscovite. SEM and EDAX studies of coating surfaces, and optical microscopy, SEM and EDXRA of very thin polished sections, show that some grainy clay coatings form as alteration rims of ferri-argillans through localized waterlogging, iron oxide loss and micro-erosion leading to micropitting and disoriented fabrics. The inclusion of coarse clay to fine silt-sized quartz, feldspar and muscovite in other grainy coatings suggests either alteration of impure ferri-argillans or accumulation of degradational products derived from elsewhere on void walls. This is more certainly the case for dark grainy coatings in layered compound illuviation coatings adjacent to glossic areas. These Fragipans are degrading from the top downwards by processes which are partly a consequence of the effects that the fragipan has on water percolation and root penetration. The destabilization of void walls, the degradation of ferri-argillans and the remobilization of clay to form glossic features did not begin until seasonal waterlogging in parts of the upper pan was sufficient to mobilize iron.
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fragipan formation in argillic brown earths fragiudalfs of the milfield plain north east england ii post devensian developmental processes and the origin of fragipan consistence
European Journal of Soil Science, 1993Co-Authors: R W PaytonAbstract:SUMMARY Pedogenetic processes following a permafrost stage of development in four argillic brown earths with Fragipans (Glossic and Ochreptic Fragiudalfs) are investigated by soil microscopy, including SEM observations of unimpregnated soil material, and by determination of clay mineralogy. Micromorphology of the apparently massive fragipan confirms both the presence of subhorizontal fissures infilled with illuvial deposits separating dense lenticular structures formed by ice-lens growth, and former vertical fissures formed by dessication on freezing with subsequent widening by ice-vein development. The firmness and brittle failure of the Fragipans are attributed to a closely-packed, well-graded matrix of skeleton grains bonded by clay bridges consisting of non-swelling illite and chlorite and to weak interconnection of macrovoids. Weak cementation is rejected as an explanation of fragipan consistence. Sequential stages of particle translocation have been critical to fragipan formation. High bulk density is attributed not only to irregular compression and contraction of the soil matrix under permafrost conditions but also to the infilling of voids by illuvial silt and clay. The full development of the Fragipans has depended on Flandrian clay migration which has contributed to clay-bridge formation, void infilling and localized seasonal impedance of drainage resulting in eluviation of iron oxides, the development of grey polygonal patterning, and processes of degradation at the pan surface leading to glossic features.
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fragipan formation in argillic brown earths fragiudalfs of the milfield plain north east england iii micromorphological sem and edxra studies of fragipan degradation and the development of glossic features
European Journal of Soil Science, 1993Co-Authors: R W PaytonAbstract:SUMMARY The micromorphology of eluvial and glossic areas with weak soi1, strength from the upper fragipan, and the upper parts of grey polygonal zones, in some argillic brown earths (Glossic Fragiudalfs) from north-east England shows unstable void walls stripped of clay with remnants of ferri-argillans, pale grey grainy clay coatings and darker grainy coatings. These occur alongside loose surface residues of skeleton grains and thin grey fine silt coatings of quartz and muscovite. SEM and EDAX studies of coating surfaces, and optical microscopy, SEM and EDXRA of very thin polished sections, show that some grainy clay coatings form as alteration rims of ferri-argillans through localized waterlogging, iron oxide loss and micro-erosion leading to micropitting and disoriented fabrics. The inclusion of coarse clay to fine silt-sized quartz, feldspar and muscovite in other grainy coatings suggests either alteration of impure ferri-argillans or accumulation of degradational products derived from elsewhere on void walls. This is more certainly the case for dark grainy coatings in layered compound illuviation coatings adjacent to glossic areas. These Fragipans are degrading from the top downwards by processes which are partly a consequence of the effects that the fragipan has on water percolation and root penetration. The destabilization of void walls, the degradation of ferri-argillans and the remobilization of clay to form glossic features did not begin until seasonal waterlogging in parts of the upper pan was sufficient to mobilize iron.
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fragipan formation in argillic brown earths fragiudalfs of the milfield plain north east england i evidence for a periglacial stage of development
European Journal of Soil Science, 1992Co-Authors: R W PaytonAbstract:SUMMARY In this first of three papers, the parent materials, morphology and field relationships of soils with Fragipans, similar to those in north-eastern United States, are described and analyses of their chemical and physical properties are presented to support a periglacial stage of development. The soil materials have been affected by periglacial processes, including ice-wedge formation, the age of which has been established by reference to a buried paleosol. The fine earth bulk density of the Fragipans is between 1.75 and 1.91 g cm−3 whereas the density of overlying Eb horizons is < 1.40 g cm−3. The formation of the compact lenticular structures and polygonal fissuring of Fragipans is ascribed to the former presence of permafrost during the Loch Lomond Stadia1 11 000 to 10 000 years B.P. The polygonal fissures, after subsequent infilling with illuvial material, have determined the position of the greyish polygonal zones which have formed by the eluviation of Fe and Mn from fissure infill and fissure walls by redox processes. Clay migration from the Eb horizon into the fragipan is well marked. Clay and silt have also been locally removed from the upper parts of the greyish zones and redeposited towards their lower parts. Similar textural degradation has affected eluvial pockets in the upper fragipan. It is concluded that periglacial processes fully explain the genesis of macrostructural features but not the distinctive consistence of the fragipan.
Mohammad Miransari - One of the best experts on this subject based on the ideXlab platform.
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formation of soils with fragipan and plinthite in old beach deposits in the south of the caspian sea gilan province iran
Applied Clay Science, 2012Co-Authors: Mostafa Karimian Eghbal, J Givi, H Torabi, Mohammad MiransariAbstract:Abstract Rice cultivation in the mountainous and sloping areas of Gilan province by leveling and terracing imposes special conditions upon the soils of these areas. Following the retreating Caspian Sea, the beach deposits left in the vicinity of the Elborz Northern foot slopes were covered by fine texture deposits. In this research, macro and micro-morphological characteristics of the soils formed in the Holocene and Pleistocene beach deposits in eastern Gilan, province, were studied. Qualitative and semi-quantitative testing of the soil reduction was carried out by using α,α′-dipyridyl indicator. Free and amorphous sesquioxides were extracted and measured by dithionite-citrate bicarbonate, and oxalate ammonium, respectively. Total Fe, Al, and Mn were measured by digestion. Polished and thin sections were used for micro-morphological description. The most important soil forming process occurring in the Apg and Bg horizons is the formation of depleted, amorphous and cryptocrystalline pedofeatures. The microstructure present in the fragipan and in the horizon characterized by the plinthite properties is mainly pellicular associated with simple packing voids. Coarse/fine (C/F) related distribution shifts from closed chitonic to gefuric. Polished sections show that the opaque minerals of the soils are mostly magnetite (60%) and hematite (40%). Magnetite weathering and its transformation to hematite (martitization process) were also observed. The results of energy dispersive analysis X-ray (EDAX) analyses showed that 40% of the sand grains coatings are iron. Fragipans have been formed in the Late Holocene beach deposits, which are more recent. This occurred when the soils with plinthite characteristics were developed in the Pleistocene beach deposits. Plinthite formation in the Iranian soils was not expected and had not been reported before. Rice cultivation and Anthric saturation may play an important role in plinthite and even fragipan formation in the studied area.
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formation of soils with fragipan and plinthite in old beach deposits in the south of the caspian sea gilan province iran
Applied Clay Science, 2012Co-Authors: Mostafa Karimian Eghbal, J Givi, H Torabi, Mohammad MiransariAbstract:Abstract Rice cultivation in the mountainous and sloping areas of Gilan province by leveling and terracing imposes special conditions upon the soils of these areas. Following the retreating Caspian Sea, the beach deposits left in the vicinity of the Elborz Northern foot slopes were covered by fine texture deposits. In this research, macro and micro-morphological characteristics of the soils formed in the Holocene and Pleistocene beach deposits in eastern Gilan, province, were studied. Qualitative and semi-quantitative testing of the soil reduction was carried out by using α,α′-dipyridyl indicator. Free and amorphous sesquioxides were extracted and measured by dithionite-citrate bicarbonate, and oxalate ammonium, respectively. Total Fe, Al, and Mn were measured by digestion. Polished and thin sections were used for micro-morphological description. The most important soil forming process occurring in the Apg and Bg horizons is the formation of depleted, amorphous and cryptocrystalline pedofeatures. The microstructure present in the fragipan and in the horizon characterized by the plinthite properties is mainly pellicular associated with simple packing voids. Coarse/fine (C/F) related distribution shifts from closed chitonic to gefuric. Polished sections show that the opaque minerals of the soils are mostly magnetite (60%) and hematite (40%). Magnetite weathering and its transformation to hematite (martitization process) were also observed. The results of energy dispersive analysis X-ray (EDAX) analyses showed that 40% of the sand grains coatings are iron. Fragipans have been formed in the Late Holocene beach deposits, which are more recent. This occurred when the soils with plinthite characteristics were developed in the Pleistocene beach deposits. Plinthite formation in the Iranian soils was not expected and had not been reported before. Rice cultivation and Anthric saturation may play an important role in plinthite and even fragipan formation in the studied area.
Mostafa Karimian Eghbal - One of the best experts on this subject based on the ideXlab platform.
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formation of soils with fragipan and plinthite in old beach deposits in the south of the caspian sea gilan province iran
Applied Clay Science, 2012Co-Authors: Mostafa Karimian Eghbal, J Givi, H Torabi, Mohammad MiransariAbstract:Abstract Rice cultivation in the mountainous and sloping areas of Gilan province by leveling and terracing imposes special conditions upon the soils of these areas. Following the retreating Caspian Sea, the beach deposits left in the vicinity of the Elborz Northern foot slopes were covered by fine texture deposits. In this research, macro and micro-morphological characteristics of the soils formed in the Holocene and Pleistocene beach deposits in eastern Gilan, province, were studied. Qualitative and semi-quantitative testing of the soil reduction was carried out by using α,α′-dipyridyl indicator. Free and amorphous sesquioxides were extracted and measured by dithionite-citrate bicarbonate, and oxalate ammonium, respectively. Total Fe, Al, and Mn were measured by digestion. Polished and thin sections were used for micro-morphological description. The most important soil forming process occurring in the Apg and Bg horizons is the formation of depleted, amorphous and cryptocrystalline pedofeatures. The microstructure present in the fragipan and in the horizon characterized by the plinthite properties is mainly pellicular associated with simple packing voids. Coarse/fine (C/F) related distribution shifts from closed chitonic to gefuric. Polished sections show that the opaque minerals of the soils are mostly magnetite (60%) and hematite (40%). Magnetite weathering and its transformation to hematite (martitization process) were also observed. The results of energy dispersive analysis X-ray (EDAX) analyses showed that 40% of the sand grains coatings are iron. Fragipans have been formed in the Late Holocene beach deposits, which are more recent. This occurred when the soils with plinthite characteristics were developed in the Pleistocene beach deposits. Plinthite formation in the Iranian soils was not expected and had not been reported before. Rice cultivation and Anthric saturation may play an important role in plinthite and even fragipan formation in the studied area.
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formation of soils with fragipan and plinthite in old beach deposits in the south of the caspian sea gilan province iran
Applied Clay Science, 2012Co-Authors: Mostafa Karimian Eghbal, J Givi, H Torabi, Mohammad MiransariAbstract:Abstract Rice cultivation in the mountainous and sloping areas of Gilan province by leveling and terracing imposes special conditions upon the soils of these areas. Following the retreating Caspian Sea, the beach deposits left in the vicinity of the Elborz Northern foot slopes were covered by fine texture deposits. In this research, macro and micro-morphological characteristics of the soils formed in the Holocene and Pleistocene beach deposits in eastern Gilan, province, were studied. Qualitative and semi-quantitative testing of the soil reduction was carried out by using α,α′-dipyridyl indicator. Free and amorphous sesquioxides were extracted and measured by dithionite-citrate bicarbonate, and oxalate ammonium, respectively. Total Fe, Al, and Mn were measured by digestion. Polished and thin sections were used for micro-morphological description. The most important soil forming process occurring in the Apg and Bg horizons is the formation of depleted, amorphous and cryptocrystalline pedofeatures. The microstructure present in the fragipan and in the horizon characterized by the plinthite properties is mainly pellicular associated with simple packing voids. Coarse/fine (C/F) related distribution shifts from closed chitonic to gefuric. Polished sections show that the opaque minerals of the soils are mostly magnetite (60%) and hematite (40%). Magnetite weathering and its transformation to hematite (martitization process) were also observed. The results of energy dispersive analysis X-ray (EDAX) analyses showed that 40% of the sand grains coatings are iron. Fragipans have been formed in the Late Holocene beach deposits, which are more recent. This occurred when the soils with plinthite characteristics were developed in the Pleistocene beach deposits. Plinthite formation in the Iranian soils was not expected and had not been reported before. Rice cultivation and Anthric saturation may play an important role in plinthite and even fragipan formation in the studied area.
J Givi - One of the best experts on this subject based on the ideXlab platform.
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formation of soils with fragipan and plinthite in old beach deposits in the south of the caspian sea gilan province iran
Applied Clay Science, 2012Co-Authors: Mostafa Karimian Eghbal, J Givi, H Torabi, Mohammad MiransariAbstract:Abstract Rice cultivation in the mountainous and sloping areas of Gilan province by leveling and terracing imposes special conditions upon the soils of these areas. Following the retreating Caspian Sea, the beach deposits left in the vicinity of the Elborz Northern foot slopes were covered by fine texture deposits. In this research, macro and micro-morphological characteristics of the soils formed in the Holocene and Pleistocene beach deposits in eastern Gilan, province, were studied. Qualitative and semi-quantitative testing of the soil reduction was carried out by using α,α′-dipyridyl indicator. Free and amorphous sesquioxides were extracted and measured by dithionite-citrate bicarbonate, and oxalate ammonium, respectively. Total Fe, Al, and Mn were measured by digestion. Polished and thin sections were used for micro-morphological description. The most important soil forming process occurring in the Apg and Bg horizons is the formation of depleted, amorphous and cryptocrystalline pedofeatures. The microstructure present in the fragipan and in the horizon characterized by the plinthite properties is mainly pellicular associated with simple packing voids. Coarse/fine (C/F) related distribution shifts from closed chitonic to gefuric. Polished sections show that the opaque minerals of the soils are mostly magnetite (60%) and hematite (40%). Magnetite weathering and its transformation to hematite (martitization process) were also observed. The results of energy dispersive analysis X-ray (EDAX) analyses showed that 40% of the sand grains coatings are iron. Fragipans have been formed in the Late Holocene beach deposits, which are more recent. This occurred when the soils with plinthite characteristics were developed in the Pleistocene beach deposits. Plinthite formation in the Iranian soils was not expected and had not been reported before. Rice cultivation and Anthric saturation may play an important role in plinthite and even fragipan formation in the studied area.
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formation of soils with fragipan and plinthite in old beach deposits in the south of the caspian sea gilan province iran
Applied Clay Science, 2012Co-Authors: Mostafa Karimian Eghbal, J Givi, H Torabi, Mohammad MiransariAbstract:Abstract Rice cultivation in the mountainous and sloping areas of Gilan province by leveling and terracing imposes special conditions upon the soils of these areas. Following the retreating Caspian Sea, the beach deposits left in the vicinity of the Elborz Northern foot slopes were covered by fine texture deposits. In this research, macro and micro-morphological characteristics of the soils formed in the Holocene and Pleistocene beach deposits in eastern Gilan, province, were studied. Qualitative and semi-quantitative testing of the soil reduction was carried out by using α,α′-dipyridyl indicator. Free and amorphous sesquioxides were extracted and measured by dithionite-citrate bicarbonate, and oxalate ammonium, respectively. Total Fe, Al, and Mn were measured by digestion. Polished and thin sections were used for micro-morphological description. The most important soil forming process occurring in the Apg and Bg horizons is the formation of depleted, amorphous and cryptocrystalline pedofeatures. The microstructure present in the fragipan and in the horizon characterized by the plinthite properties is mainly pellicular associated with simple packing voids. Coarse/fine (C/F) related distribution shifts from closed chitonic to gefuric. Polished sections show that the opaque minerals of the soils are mostly magnetite (60%) and hematite (40%). Magnetite weathering and its transformation to hematite (martitization process) were also observed. The results of energy dispersive analysis X-ray (EDAX) analyses showed that 40% of the sand grains coatings are iron. Fragipans have been formed in the Late Holocene beach deposits, which are more recent. This occurred when the soils with plinthite characteristics were developed in the Pleistocene beach deposits. Plinthite formation in the Iranian soils was not expected and had not been reported before. Rice cultivation and Anthric saturation may play an important role in plinthite and even fragipan formation in the studied area.
H Torabi - One of the best experts on this subject based on the ideXlab platform.
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formation of soils with fragipan and plinthite in old beach deposits in the south of the caspian sea gilan province iran
Applied Clay Science, 2012Co-Authors: Mostafa Karimian Eghbal, J Givi, H Torabi, Mohammad MiransariAbstract:Abstract Rice cultivation in the mountainous and sloping areas of Gilan province by leveling and terracing imposes special conditions upon the soils of these areas. Following the retreating Caspian Sea, the beach deposits left in the vicinity of the Elborz Northern foot slopes were covered by fine texture deposits. In this research, macro and micro-morphological characteristics of the soils formed in the Holocene and Pleistocene beach deposits in eastern Gilan, province, were studied. Qualitative and semi-quantitative testing of the soil reduction was carried out by using α,α′-dipyridyl indicator. Free and amorphous sesquioxides were extracted and measured by dithionite-citrate bicarbonate, and oxalate ammonium, respectively. Total Fe, Al, and Mn were measured by digestion. Polished and thin sections were used for micro-morphological description. The most important soil forming process occurring in the Apg and Bg horizons is the formation of depleted, amorphous and cryptocrystalline pedofeatures. The microstructure present in the fragipan and in the horizon characterized by the plinthite properties is mainly pellicular associated with simple packing voids. Coarse/fine (C/F) related distribution shifts from closed chitonic to gefuric. Polished sections show that the opaque minerals of the soils are mostly magnetite (60%) and hematite (40%). Magnetite weathering and its transformation to hematite (martitization process) were also observed. The results of energy dispersive analysis X-ray (EDAX) analyses showed that 40% of the sand grains coatings are iron. Fragipans have been formed in the Late Holocene beach deposits, which are more recent. This occurred when the soils with plinthite characteristics were developed in the Pleistocene beach deposits. Plinthite formation in the Iranian soils was not expected and had not been reported before. Rice cultivation and Anthric saturation may play an important role in plinthite and even fragipan formation in the studied area.
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formation of soils with fragipan and plinthite in old beach deposits in the south of the caspian sea gilan province iran
Applied Clay Science, 2012Co-Authors: Mostafa Karimian Eghbal, J Givi, H Torabi, Mohammad MiransariAbstract:Abstract Rice cultivation in the mountainous and sloping areas of Gilan province by leveling and terracing imposes special conditions upon the soils of these areas. Following the retreating Caspian Sea, the beach deposits left in the vicinity of the Elborz Northern foot slopes were covered by fine texture deposits. In this research, macro and micro-morphological characteristics of the soils formed in the Holocene and Pleistocene beach deposits in eastern Gilan, province, were studied. Qualitative and semi-quantitative testing of the soil reduction was carried out by using α,α′-dipyridyl indicator. Free and amorphous sesquioxides were extracted and measured by dithionite-citrate bicarbonate, and oxalate ammonium, respectively. Total Fe, Al, and Mn were measured by digestion. Polished and thin sections were used for micro-morphological description. The most important soil forming process occurring in the Apg and Bg horizons is the formation of depleted, amorphous and cryptocrystalline pedofeatures. The microstructure present in the fragipan and in the horizon characterized by the plinthite properties is mainly pellicular associated with simple packing voids. Coarse/fine (C/F) related distribution shifts from closed chitonic to gefuric. Polished sections show that the opaque minerals of the soils are mostly magnetite (60%) and hematite (40%). Magnetite weathering and its transformation to hematite (martitization process) were also observed. The results of energy dispersive analysis X-ray (EDAX) analyses showed that 40% of the sand grains coatings are iron. Fragipans have been formed in the Late Holocene beach deposits, which are more recent. This occurred when the soils with plinthite characteristics were developed in the Pleistocene beach deposits. Plinthite formation in the Iranian soils was not expected and had not been reported before. Rice cultivation and Anthric saturation may play an important role in plinthite and even fragipan formation in the studied area.
