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An approach to studying soil-landscape relationships in VirginiaStolt, Mark H. 13 October 2005 (has links)
Various methods and techniques were used to examine soil-landscape relationships for residual and colluvial soils of Virginia. Soil micromorphology indicated that although some BC and C horizons in the field appeared structureless, evidence of pedogenic process was observed. These were designated as either BCt, BC, or CB horizons depending on the amount of oriented clay and the rates of change with depth of clay, DCB extractable Fe, and sand contents. Soil variability was examined for the overall study, as well as within toposequences, pedons, and individual horizons. Most of the overall variability was attributed to differences between study sites or between horizons, with minimal amounts due to landscape position. Substantial lateral variability occurred within horizons indicating a strong need for subsampling within horizons of the same pedon. Lithologic discontinuities were found to be difficult to recognize without obvious field evidence. Reconstruction analysis was used to examine soil and saprolite formation. Summit and backslope soils were found to be essentially the same in both morphology and degree of profile development. Sand weathering and clay eluviation/illuviation were the major soil forming processes occurring within these soils. Footslope soils were less developed than associated summit and backslope soils, with both depositional and pedologic processes contributing to soil formation and development. Thickness of saprolite was found to decrease. from the summit to the footslope. Thicker saprolite at the summit was apparently related to the greater stability of the summit position compared to the backslope and footslopes. A bucket auger was modified to obtain undisturbed samples of deep saprolite for reconstruction analysis. Saprolite reconstruction indicated that between 20 and 36 % of the mass of the partially weathered rock, which is the precursor to saprolite, is lost during saprolite formation. Most of these losses were either Al or Si. Initial soil formation was shown to occur at a faster rate than saprolite formation, but after substantial profile development, soil formation is reduced to a rate below that of saprolite formation, and saprolite accumulates below the solum. Reconstruction analysis was found to be a valuable tool in studying soil-landscape relationships. / Ph. D.
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Soil genesis studies of upland soils formed in transported materials overlying the Virginia Piedmont using trend-surface analysesSaxton, H. Thomas 10 January 2009 (has links)
Soils overlying residuum on upland divides and interfluves that formed from transported material are common in the Virginia Piedmont. They are thought to occur on the oldest landscapes in the region. A study was initiated in Appomattox County and a small portion of Buckingham County encompassing an area of 238 square miles. The origin, age and characterization of these soils is studied. Mapping units comprised of red subsoil components and mapping units with non-red subsoil components are compared. Trend-surface analysis of the elevations at which they occur and chemical and physical data from twenty-four pedons in Appomattox County are used.
The mapping units contain a complex mixture of taxonomic classifications that encompass pedons with and without palic clay distributions. Wetness due to perched water tables at variable depths also affects classifications.
The red subsoil mapping units tend to occupy the older landscapes. Age estimates are derived from a comparison of trend-surface elevations between the transported soils and the present-day surface. These comparisons result in age estimates of 0.8 million years to 6.25 million years BP. Therefore, the oldest geomorphic surfaces in the south central Piedmont of Virginia may be estimated as late Pliocene to Miocene age landscapes. These soil materials were deposited through a process of landscape inversion dominated by subsidence and colluviation. / Master of Science
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Soil Formation on the Namaqualand Coastal PlainFrancis, Michele Louise 03 1900 (has links)
Thesis (PhD (Soil Science))--Univ ersity of Stellenbosch, 2008. / The (semi-)arid Namaqualand region on the west coast of South Africa is wellknown
for its spring flower displays. Due to the aridity of the region, soils research
has lagged behind that of the more agriculturally productive parts of South
Africa. However, rehabilitation efforts after the hundred or so years of mining,
coupled with the increasing ecology and biodiversity research, have prompted
a recent interest in Namaqualand soils as a substrate for plant growth. The
area is also notable for the abundance of heuweltjies. Much of the previous
heuweltjie-work focussed on biogenic aspects such as their spacing, origin and
age, but although heuweltjies are in fact a soil feature, there have been few
published studies on the soil forming processes within heuweltjies. However, the
depositional history of the sediments on the Namaqualand coastal plain is well
constrained, which is in stark contrast to the paucity of data on their subsequent
pedogenesis. Given that the regolith has been subaerially exposed in some parts
for much of the Neogene, the soil formation forms an important part of the
sediments’ history. The primary aim of this thesis, therefore, was to examine the
soil features of the Namaqualand coastal plain to further the understanding of
pedogenesis in the region.
The regolith of the northern Namaqualand coastal plain, often ten or more metres
deep, comprises successive late Tertiary marine packages, each deposited during
sea-level regression. The surface soil horizons formed from an aeolian parent
material. The relatively low CaCO3 in the aeolian sands dictated the pedogenic
pathway in these deposits. The non-calcareous pathway lead to clay-rich, redder
apedal horizons that show a stronger structure with depth, and generally rest
directly on marine sands via a subtle discontinuity that suggests pedogenesis continues
into the underlying marine facies. The calcareous pathway lead to similar
clay-rich, redder apedal B horizons, but which differ in that they are calcareous, and rest on a calcrete horizon often via a stoneline of rounded pebbles. Deeper in
the profile, there is generally a regular alteration of sedimentary units, with the
upper shoreface facies showing reddening, and the lower shoreface sands remaining
pale. This seems to be a function of the grain size, since the upper shoreface
materials are coarser, and the redder parts of the lower shoreface are also associated
with slightly coarser sands. In some strata the oxidation of glauconite-rich
sediments resulted in an orange colour. In an area with abundant heuweltjies, a
strongly-cemented calcretized nest was present about 2 m deep within a silica cemented,
locally calcareous dorbank profile. Vertical termite burrows are present
up to 12 m deep, and appear to have been conduits for preferential vertical flow.
Soil formation and termite activity is at least as old as the Last Interglacial. E
horizons may have formed in a wetter Last Interglacial paleoclimate, but they
are still active in the present day.
The Namaqualand coastal plain, with its extensive areas of calcrete development,
is almost a textbook setting for calcrete development by inorganic processes.
However, these calcretes also show microscale biogenic features. These include
M rods, MA rods, and fungal filaments. Abiotic alpha-fabric seems dominant
in mature calcrete horizons, and beta-fabric in calcareous nodules in a calcic
B horizon above calcrete. The apparent absence of Mg-calcite and dolomite,
and abundance of sepiolite in the calcretes of coastal Namaqualand suggests
that these Mg-rich clay minerals are the main Mg-bearing phase. Deformation
(pseudo-anticlines) in the calcrete appear to result primarily from the displacive
effect of calcite crystallization. Although evidence of shrink/swell behaviour
is present in the form of accommodating planes, it does not appear to be as
volumetrically significant as displacive calcite.
Indurated light-coloured horizons that resembled calcrete but are non- to mildly
calcareous, break with a conchoidal fracture, resist slaking in both acid and alkali,
turn methyl-orange purple, and show a bulk-soil sepiolite XRD peak are
similar to palygorskite-cemented material (‘palycrete’) from Spain and Portugal,
and so were tentatively named ‘sepiocrete’. Sepiolite and palygorskite are often
reported from arid region soils but there has been no recorded cementation of
soils by sepiolite. The degree of induration in some of these horizons suggest that
amorphous silica could play a role in cementation, and so this thesis compares
the two silica-cemented horizons encountered in Namaqualand (silcrete and dorbank
(petroduric)) to these ‘sepiocrete’ horizons. Both silica and sepiolite are present in the matrix, although the degree to which silica and sepiolite dominate
seems to vary even within same horizon. It seems most probable that both
contribute to the structural properties of the horizon. Sepiolitic horizons do not
form a diagnostic horizon in the World Reference Base, Soil Taxonomy, or the
South African system. To fit the existing soil classification schemes, the terms
‘sepiolitic’ and ‘petrosepiolitic’ (in the same sense as ‘calcic’ and ‘petrocalcic’)
would be appropriate. The term ‘sepiolitic’ should be used for horizons which:
contain sepiolite in amounts great enough for it to be detected by XRD in the
bulk soil, peds (a fractured surface and not just the cutan) cling strongly to the
wetted tongue, and methyl orange turns from orange to purple-pink over most
of a fragmented surface. The term can be easily be applied as a adjective to
other hardpans where sepiolite is significant but not necessarily cementing, such
as ‘sepiolitic’ petrocalcic/petroduric. If the horizon is in addition to the above
criteria cemented to such a degree that it will slake neither in acid (so cannot be
classified as petrocalcic) nor in alkali (and so cannot be classified as petroduric)
then the term ‘petrosepiolitic’ would be appropriate. The ‘sepiolitic’ criteria distinguish
the ‘petrosepiolitic’ horizon from a ‘silcrete’, a silica-cemented horizon
which does not fit the definition of petroduric.
Sepiolite is more prominent than palygorskite in the XRD traces. The <0.08 μm
fraction is the only size fraction where palygorskite could be detected before
acetate treatment. It is unlikely that these fibrous clay minerals are inherited
from either the marine or aeolian parent materials, they appear to be pedogenic
in origin. Sepiolite and palygorskite are associated with the presence of calcite
in the soil profile. Trends in MgO, Al2O3 and SiO2 show that the soil clay
fractions lie on a mixing line between sepiolite and mica end-members, with a
contribution from smectite, and is consistent with the XRD and TEM results.
There is a good correlation between Fe2O3 and TiO2, which can be attributed
to the ubiquitously presence of mica. There was no TEM evidence of fibrous
mineral degradation to sheet silicates, nor for the evolution of mica laterally to
a fibrous mineral. SEM analyses show that much of the sepiolite/palygorskite
occurs as fringed sheets, but higher magnification often revealed these sheets
to be composed of fibres. These are found coating (rather than evolving from)
mica/illite particles, as free-standing mats, and are common on the grain-side of
cutans. Some of these textures suggest illuviation of the fibrous clay minerals,
but another explanation may be that sites such as that immediately adjacent to silicate grains have the highest concentration of silica for their formation.
There was no conclusive evidence for or against the presence of kerolite in the
clay fraction, although it does not appear to be a dominant phase in the <2 μm
fraction.
The hypothesis was that the permeable upper horizons in Namaqualand soils
constitute a shallow ephemeral aquifer, which can be considered the pedogenic
analogue of the saline lake environments in which sepiolite typically forms. The
chemical evolution of the soil solution and clay mineral genesis could therefore be
considered in the same terms as the geochemical evolution of closed-basin brines.
The Namaqualand coastal plain, like other maritime areas, shows a trend of decreasing
pH, increasing Ca and increasing Mg with increasing evaporation. This
can be explained by their seawater-influenced initial ratios, and is consistent with
the ‘chemical divides’ of the Hardie-Eugster model of brine evolution. Halite remains
undersaturated at all concentrations in the saturated paste extracts. At
higher concentrations, gypsum reaches saturation, and sulfate is removed from
solution. H4SiO4 activity remains unchanged for all levels of evaporation and
pH. Calcite remains close to saturation, and is only dependent on the HCO−3
activity and pH for the range of Cl− activity encountered. Most of the soils for
which there is a positive sepiolite identification show a positive sepiolite saturation
index. The sepiolite saturation index is independent of Mg2+ and H4SiO4
and only increases with increasing pH. Evidence of the pH control on sepiolite
saturation is that sepiolite is commonly associated with calcareous horizons.
Sepiolite precipitation is therefore more likely to be triggered when a solution
encounters a pH barrier than by the concentration of ions by evaporation. The
effect of a pH change on the sepiolite saturation index is much greater than that
of the effect on calcite. The marine-influenced high Mg coupled with the Hardie-
Eugster model of brine evolution offers an explanation for sepiolite-dominance at
the coast, and palygorskite-dominance inland. Coastal areas, unlike continental
areas, have Mg>HCO−3 initially, which results in an increasing Mg trend with
evaporation during the precipitation of sepiolite according to the Hardie-Eugster
scheme. The result is that after sepiolite precipitation is initiated by a geochemical
pH-barrier, Mg levels will rise causing the increasing (Mg+Si)/Al ratio to
continue to favour sepiolite precipitation. This suggests that once sepiolite has
begun to precipitate, the subsequent salinity with its accompanying Mg increase
makes substantial palygorskite formation unlikely to follow. The hardpan horizons in heuweltjies commonly grade from a ‘sepiolitic’ petrocalcic
in the centre through ‘sepiolitic’/‘petrosepiolitic’ to the petroduric horizon
on the edges. Noteworthy sepiolite-related pedofeatures in the calcrete include
‘ooids’ with successive sepiolite (hydrophilic and therefore a precipitational substrate)
and micrite/acicular calcite layers in the coatings; and limpid yellow
nodules with pseudo-negative uniaxial interference figures. They superficially
resemble the spherulites in the fresh termite frass. Their fibrous nature and low
birefringence, together with the low Ca, high Mg, Si composition, and molar
Mg/Si ratios consistent with sepiolite. The pedogenesis of the hardpans in the
heuweltjie is proposed to be as follows: enrichment of cations such as Ca and
Mg in the heuweltjie centre caused by termite foraging results in calcite and clay
authigenesis in the centre of the heuweltjie, leaving the precipitation of pure silica
to occur on the periphery. The decaying organic matter concentrated in the
centre of the mound by the termites is sufficient to supply the components for
calcite precipitation in the centre of the heuweltjie. Following calcite precipitation,
the pH is suitable for sepiolite precipitation. The movement of the Mg-Si
enriched water downslope, coupled with the decrease in HCO−3 and increase in
Mg2+ due to sepiolite precipitation, allows for the precipitation of the ‘sepiolitic’
zone on the outer side of the calcrete, and extend beyond the calcrete in some
heuweltjies.
The Namaqualand coastal plain is well positioned for further work on its regolith,
particularly because of the mining excavations which provide excellent exposures
of well-defined layers of the regolith down to bedrock. Soil formation and termite
activity is at least as old as the Last Interglacial, and so more detailed work would
further the understanding of the subaerial alteration history in southern Africa,
as well as providing better-constrained information on the Namaqualand soils
that can be used by land-use management and biosphere studies.
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Spatial analysis of soil depth variability and pedogenesis along toposequences in the Troodos Mountains, CyprusRobins, Colin R. 17 August 2004 (has links)
In unstable landscapes, modern pedological research explores the role of
soils as products and indicators of geomorphologic change. Understanding the
dynamics of hill slope pedogenesis is especially important in regions with limited,
poor, or threatened soil resources. The island of Cyprus, situated in the eastern
Mediterranean, is claimed by many authors to exhibit signs of severe soil
degradation and is a prime site for comparative soil geomorphologic research. This
study strove to 1) identify the controls of soil genesis and landscape stability within
the Troodos Mountains of Cyprus using image and GIS analysis; 2) compare
toposequence data to expected soil thickness trends from traditional models of xeric
soil toposequences prevalent in current scientific literature; and 3) develop a
predictive model for hillslope pedogenesis based on measured soil properties
within the field area.
Study soils within the Troodos are thin, weakly developed Lithic and Typic
Xerorthents formed in colluvium derived from fractured, igneous bedrock. Soil
thickness was measured at 368 sites in seven transects across three watersheds in
the Troodos, using interpretations of field profiles and image analysis of digital
soil-bedrock profiles in photographed road-cuts along forestry paths. Soil thickness
was compared through GIS and statistical analysis to landscape attributes derived
from a 25-m DEM and other map data. Results indicate that lithology is the only
factor of several studied to have a significant relationship with the variability of
soil-profile thickness in the Troodos, and that soil thickness does not vary in a
predictable manner across toposequences. These results, combined with differences
between measured soil data and values predicted by the landscape stability model
SHALSTAB, suggest that soil genesis in the Troodos is best described only within
the context of a weathering-limited geomorphological system.
Short-term disruptive processes such as forest fires, land sliding, tree throw,
and raindrop impact, combined with long-term processes such as tectonic uplift and
stream incision, are the most likely driving forces behind the rapid erosion of hill
slope sediments and the weak development of Troodos hill slope soils. These
findings have important implications for DEM-based, predictive soil mapping in
weathering-limited geomorphologic systems. / Graduation date: 2005
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Soil genesis and vegetation growth in pulverized fuel ash and refuse landfills capped by decomposed graniteNgai, Yuen-yi, Helen., 魏婉儀. January 1998 (has links)
published_or_final_version / Geography and Geology / Master / Master of Philosophy
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Climatic and Tectonic Implications of a mid-Miocene Landscape: examination of the Tarapaca Pediplain, Atacama Desert, ChileLehmann, Sophie Butler 13 August 2013 (has links)
No description available.
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Continuity and change in arable land management in the Northern Isles : evidence from anthropogenic soilsGuttmann, E. B. January 2001 (has links)
Human activity can affect the soil in ways which are traceable long after the land has been given over to other uses, and past land management practices can be reconstructed by investigation of these relict characteristics. In some regions the addition of fertilising materials to the arable soils has created artificially deepened anthropogenic topsoils which can be over 1m thick. Such relict soils are found all over the world, and are widespread in north-western Europe. This work focuses on the anthropogenic soils in the Northern Isles, which were formed from the Neolithic period up until the 20th century. Three multi-period sites were investigated using thin section micromorphology, organic/inorganic phosphate analysis, soil magnetism, particle size distribution, loss on ignition and soil pH. Current views of anthropogenic soil formation, based on pedological investigation and historical documentary sources, are that they are formed as a result of the addition of domestic animal manures and turf used as animal bedding to arable areas. This project sets out to test the hypothesis that in fact anthropogenic soils are the result of a wide range of formation processes which took place over extended periods of time. The hypothesis has been tested by analysing soils and associated middens of different dates, which have been sealed and protected by blown sand deposits. The results have shown that in the Neolithic period arable soils were created by cultivating the settlement's midden heaps as well as by adding midden material to the surrounding soils. In the Bronze Age human manure, ash and domestic waste were spread onto the fields around the settlements to create arable topsoils up to 35cm thick. In the Iron Age arable agriculture was intensified by selective use of organic manures on one of the sites investigated, but organic waste material was not used as efficiently as it was in later periods, and on both sites it was allowed to accumulate within the settlements. In the Norse period, when the intensive system used in historical times appears to have originated, organic waste may have been used more efficiently. These changes appear to reflect a greater organisation of land resources and manuring strategies and increased demand for arable production over time.
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Organossolos: morfologia, atributos f?sicos, qu?micos e abund?ncia natural de is?topos de carbono e nitrog?nio / Histosols: Morphology, physical and chemical attributes, and carbon and nitrogen isotopic natural abundanceSOARES, Paula Fernanda Chaves 25 February 2015 (has links)
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Previous issue date: 2015-02-25 / CAPES / According to the Brazilian Soil Classification System the Organossolos (Histosols) are characterized by horizons with high organic matter content and a given thickness. The carbon content is related to pedogenesis processes; however for the carbon addition and maintenance in the soil in such amount and thickness to meet the criteria of the classification system there are several factors working in conjunction, culminating in the soil genesis process. These soils can be formed by paludization or litter accumulation. The overall objective of the study was to characterize and classify Organossolos and to verify the influence of their genesis in the soil attributes, evaluating physical and chemical properties; in addition, the application of isotopic methods for analyzing natural abundance of carbon and nitrogen isotopes, relating the data with changes in vegetation and in soil evolution. The soils are under Atlantic Forest in the state of Rio de Janeiro. There were selected four profiles in different environments, one in the municipality of Mag? in the plains neighboring the Guanabara Bay, the second in Campos dos Goytacazes municipality, near Lagoa Feia, both in hot and humid climate and lowland plain relief. Two other soil profiles were located in Itatiaia municipality, in the highland section of the Itatiaia National Park, under cold weather and humid and mountainous vegetation environment. A series of analytical procedures were made: description and morphological characterization, analysis of chemical and physical properties, determination of carbon and nitrogen, chemical fractionation of humic substances, mineral material (MM), density of organic matter (DOM), minimum residue (MR), solubility in sodium pyrophosphate (SSP), determination of fibers and Von Post decomposition scale; plus the quantification of natural abundance of carbon isotopes (12C and13C) and nitrogen (14N and 15N), and carbon dating by the method of C. The RJ-01 profile was classified as ORGANOSSOLO Tiom?rfico S?prico t?pico, the RJ-02 as ORGANOSSOLO H?plico S?prico t?pico, the RJ-03 as ORGANOSSOLO H?plico H?mico t?pico and RJ-04 as ORGANOSSOLO F?lico S?prico cambiss?lico, equivalent to Sulfosaprists (RJ-01) Haplosaprists (RJ-02), Haplohemists (RJ-03) and Udifolists (RJ-04), in the Soil Taxonomy (USDA-NRCS). The RJ- 01 was significantly thicker and higher in carbon content in the subsurface. The RJ-02 profile was shallower, but had a higher organic matter deposition. The RJ-03 profile had the organic matter (OM) with the oldest C dating, in the range of 3351-3699 years at 40-50 cm. However, the RJ-04 profile stood out from the others because it had better soil drainage, higher degree of OM humification. Also, this profile had a variation of ?6 of 13C, indicating a change in local floristic composition with an increase of vegetation with C3 photosynthetic cycle, which is a hint of climate change. / De acordo com o Sistema Brasileiro de Classifica??o de Solo os Organossolos s?o caracterizados por horizontes com elevado teor de material org?nico e uma espessura m?nima. O teor de carbono esta ligado ao processo pedogen?tico, por?m para que ocorra a adi??o e manuten??o de carbono em quantidade e espessura de forma a atender os crit?rios do sistema de classifica??o uma s?rie de fatores atua em conjunto, culminando com o processo de g?nese do solo. Esses solos podem ser formados atrav?s de um desses processos: paludiza??o ou acumula??o de liteira. O objetivo geral do trabalho foi caracterizar e classificar Organossolos e verificar a influ?ncia da sua g?nese sobre os atributos ed?ficos, analisando as propriedades f?sicas e qu?micas; ainda a aplica??o de m?todos de an?lise da abund?ncia natural de is?topos de carbono e nitrog?nio, relacionando-as as altera??es na vegeta??o e na evolu??o do solo, em dois ambientes de Floresta Atl?ntica, no Estado do Rio de Janeiro. Para tanto foram selecionados quatro perfis em locais distintos, um em Mag? ao fundo da Ba?a de Guanabara, o segundo em Campos dos Goytacazes pr?ximo a Lagoa Feia, ambos em ambientes de clima quente e ?mido e relevo plano de v?rzea. Outros dois perfis localizam-se em Itatiaia, na parte alta do Parque Nacional de Itatiaia (PNI), em ambiente de clima frio e ?mido e vegeta??o altomontana. Realizou-se uma s?rie de procedimentos anal?ticos: descri??o e caracteriza??o morfol?gica, an?lises de atributos qu?micos e f?sicos, determina??o de carbono e nitrog?nio, fracionamento qu?mico das subst?ncias h?micas, material mineral (MM), densidade da mat?ria org?nica (DMO), res?duo m?nimo (RM), solubilidade em pirofosfato de s?dio (IP), determina??o de fibras (FE e FN) e escala de decomposi??o de Von Post, abundancia natural de is?topos do carbono (12C e 13C) e nitrog?nio (14N e 15N) e data??o da mat?ria org?nica do solo atrav?s do m?todo de C. O perfil RJ-01 foi classificado como ORGANOSSOLO Tiom?rfico S?prico t?pico, o RJ-02 como ORGANOSSOLO H?plico S?prico t?pico, o RJ-03 como ORGANOSSOLO H?plico H?mico t?pico e o RJ-04 como ORGANOSSOLO F?lico S?prico cambiss?lico. O perfil RJ-01 apresentou maior espessura e teores de carbono mais elevados em subsuperf?cie. O perfil RJ-02 foi o de menor profundidade, por?m possui maior deposi??o atual de mat?ria org?nica (MO). O perfil RJ- 03 possui a MO mais antiga, datando na faixa de 3351-3699 anos a 40-50 cm. No entanto, o perfil RJ-04 destacou-se dos demais por apresentar melhor drenagem e maior grau de humifica??o da MO. Al?m disso, esse perfil mostrou varia??o do valor de C de ?6, indicando altera??o na composi??o flor?stica local, com o aumento de vegeta??o do ciclo fotossint?tico C3, o que ? apontado como ind?cio de altera??es clim?ticas.
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Quaternary marine terraces on Cyprus : constraints on uplift and pedogenesis, and the geoarchaeology of PalaipafosZomeni, Zomenia 12 June 2012 (has links)
Numerous flights of Quaternary marine terraces are present around the island of Cyprus, in the Eastern Mediterranean. These terraces are a result of the global eustatic sea-level curve and local tectonism. Marine Isotope Stage (MIS) 5 through MIS 13 terraces are identified, mapped and dated. Palaeoshoreline elevation, an excellent indicator for a past sea–level, and new numerical geochronology are used to calculate an Upper Pleistocene uplift rate for various coastal sectors. Southwestern Cyprus presents the highest uplift rates of 0.35-0.65 mm/year with other sections suggesting uplift of 0.07-0.15 mm/year. This Upper Pleistocene tectonic signal is attributed to an active offshore subduction/collision system to the southwest of Cyprus, evidenced from the seismic activity offshore and the surface expression of a blind thrust fault in the Pafos region.
Soil chronosequences and geology in southwestern Cyprus are studied in order to understand the Quaternary development on this uplifting landscape. Soil profile properties are used to calculate a profile development index (PDI), a method often applied to geomorphic surfaces as a relative dating method. Well-developed red and clayey soils occur in the coastal sector, on broad and low-angle surfaces, specifically on marine terraces and alluvial fans. Higher elevations of steep slopes consisting of carbonate and ophiolite lithologies host poorly developed soils. Results show variable PDI's on uplifted terraces, obscured by transported materials, active alluvial fan buildup and hillslope erosion. Calcium carbonate build-up in soil profiles in the form of nodular and laminar accumulations are used as another relative dating method. Geochronology of marine terraces is used as an age range approximation for carbonate stages.
Geomorphologic mapping focuses on the southeastern part of the Pafos thrust fault, the only point on the landscape where this otherwise blind fault is exposed on the surface. This is the location of Palaipafos, an important Ancient polity, today the site of the village of Kouklia. Geoarchaeological study suggests little landscape change over the last 4000 years in the vicinity of the urban core of Palaipafos, this being attributed to bedrock and landscape resistance of its location, a plateau at 80 m amsl. Copper deposits in the Palaipafos hinterland had provided a valuable resource at one time. Soil and water resources continue to sustain agriculture.Tectonic uplift in this part of the Pafos thrust fault is estimated to be 2.1mm/year, considered, together with Late Holocene sea-level change responsible for the shifting locations and eventual abandonment of the Palaipafos harbor in the coastal lowlands. / Graduation date: 2013
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Late-glacial through Holocene Stratigraphy and Lake-level Record of Rangely Lake, Western MaineMetcalfe, Elisabet Joan January 2007 (has links) (PDF)
No description available.
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