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An investigation of the Holocene pollen record from the Grey Islands, Newfoundland /Evans, Nicola S., January 2002 (has links)
Thesis (M.Sc.)--Memorial University of Newfoundland, 2003. / Bibliography: leaves 102-109.
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A formação Irati (Grupo Passa Dois, Permiano, Bacia do Paraná) no furo de sondagem FP-01-PR (Sapopema, PR)Lages, Leandra Costa [UNESP] 21 October 2004 (has links) (PDF)
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lages_lc_me_rcla.pdf: 2576438 bytes, checksum: 0c22ef1df77c569ffd1118f9e6084192 (MD5) / Agência Nacional do Petróleo, Gás Natural e Biocombustíveis (ANP) / A Formação Irati (Grupo Passa Dois, Permiano, Bacia do Paraná), subdividida nos membros Taquaral e Assistência, foi estudada no furo FP-01-PR da CPRM em Sapopema, PR (UTM 7.384.500N/562.000E), onde apresenta 44,5 m de espessura. Visando discutir os paleoambientes e a idade da formação, o trabalho envolveu descrições dos testemunhos, petrografia dos carbonatos, geoquímica dos pelitos (%COT e %S), palinologia e correlações estratigráficas. Os principais resultados inéditos são: 1) O Membro Taquaral, embora predominantemente síltico, apresenta finas coquinas de bivalves e porções areno-margosas no final de um ciclo granocrescente ascendente. 2) Tanto na base, quanto no topo da formação, há prováveis lags transgressivos constituídos por delgados bone beds de peixes. 3) Correlações entre furos da borda leste da bacia revelaram modificações na taxa de subsidência na região do Arco de Ponta Grossa, de relativamente alta para baixa, respectivamente para os membros Taquaral e Assistência. Tal fato e as marcantes diferenças litofaciológicas sugerem a separação dos membros por discordância. 4) As assembléias palinológicas, embora mal preservadas e constituídas quase apenas por grãos de pólen, algas Bothryococcus (dulçaqüícolas) e acritarcas (marinhos), indicam idade artinskiana por correlações com a África. 5) Análises críticas e algumas interpretações alternativas são apresentadas em relação aos paleoambientes e às seqüências estratigráficas. / The Irati Formation (Permian Passa Dois Group, Paraná Basin) divided into the Taquaral and Assistência members, is 44,5 m thick in CPRM's FP-01-PR borehole at Sapopema Municipality, Paraná State (UTM 7.384.500N/562.000E). Aiming paleoenviromental and age discussions, the work envolves description of cores, carbonate petrography, geochemistry of pelites (%TOC and %S), palynology and stratigraphic correlations. The main inedit results are: 1) The predominantely siltic Taquaral Member has thin bivalve coquinas and sandy marl portions at the end of a coarsening upwards cycle. 2) Both at the base and the top of the formation, there are probable transgressive lags constituted of thin fish bone-beds. 3) Correlations between boreholes at the eastern border of the basin reveal modifications in the subsidence rate in the region of the Ponta Grossa Arch, from relatively high to low, respectively for the Taquaral and Assistência members. This fact and the strong lithofaciological differences suggest a discordant boundary between the members. 4) The palynological assemblages, although badly preserved and almost exclusively constituted of pollen grains, Bothyococcus algae (freshwater) and acritharcs (marine), through correlations with Africa, indicate an Artinskian age. 5) Critical analysis and some alternative interpretations are presented for the paleoenvironments and stratigraphic sequences.
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Palynology, thermal maturation, and time temperature history of three oil wells from the Beaufort-Mackenzie BasinForman, Robert Douglas January 1988 (has links)
Palynological and maturation data are combined to reconstruct the burial and thermal history of three oil wells in the Beaufort-Mackenzie Basin. From south to north, the three wells are Netserk F-40, Tarsuit A-25, and Orviiruk 0-03.
Each well was examined palynologically and zoned based on species ranges of pollen, spores, fungi, and algal cysts. Using local extinction events of zonally diagnostic species to define the tops of intervals, seven informal palynozones are presented: Laevigatosporites (Pleistocene); ChenopodipoJlis (Pliocene to early Pleistocene); Ericipites (middle to late Miocene); Selenopemphix-1 (middle to late Oligocene); Integricorpus (early Oligocene); Araliaceoipollenites (late Eocene to early Oligocene); Pistillipollenites (middle Eocene).
Correlations within the basin indicate that the proposed zonation may be useful for local correlations. Correlations outside the basin indicate that the palynological assemblages from the Beaufort-Mackenzie Basin may not be as isolated and endemic as first thought.
A high recovery of algal cysts is attributed to less harsh maceration techniques, and confirms a significant population of cysts from a region in which they were formerly believed to be relatively scarce.
The palynology does not exhibit an increase in marine influence with decreasing proximity to the basin margin. Instead it shows a consistent, strong terrestrial influence throughout each well. The large terrestrial discharge from the Mackenzie River is interpreted to have masked the effect of basin proximity on the palynology of the area.
The study wells are dominated by terrestrial Type III organic matter. Recycled and terrestrial inert material often make up over 95 % of the residues. These results support a terrestrial source for the offshore oils in the Beaufort -Mackenzie Basin.
There is a small but consistent presence of potential oil-generating material throughout each well (amorphous and liptinite). The liptinite is largely composed of pollen grains, spores, and leaf cuticle. Algal cysts are present but less abundant. If the observed amounts of amorphous and liptinite material continue to some depth, where the required level of thermal maturation might be reached, these sediments could act as source rocks for hydrocarbons.
The rare occurrence of resinite in the study wells questions the resinite source theory for the hydrocarbons in the basin
The sediments in each of the three study wells are immature to total depth, and could not be the source of Tertiary oils in the Beaufort - Mackenzie Basin. The levels of maturity in the wells, and the low maturation gradient calculated for Netserk F-40 (0.07 Ro/km), suggest that thermal maturation will only be achieved at much greater depths. This is most likely due to rapid sedimentation rates in the basin during the Tertiary.
By combining the zonations from Chapter 3 with the maturation data from Chapter 4, the burial and thermal history of each study well is reconstructed. Using a modified version of Lopatin's method, paleo-geothermal gradients are calculated for each well. In each case, the gradient that best accountes for the measured maturities is 15 °C/km.
The calculated gradient is approximately 1/2 to 1/3 of the present geothermal gradients for the wells. The gradient is in agreement with those previously calculated from similar basins, and is considered responsible for the failure of any of the study wells to encounter effective source rocks.
Source rocks of Tertiary oils in the Beaufort-Mackenzie Basin will only exist at greater depths than those encountered in this study. Prospective targets may therefore be located adjacent to sites where vertical migration of hydrocarbons is likely, such as steeply-dipping faults. / Science, Faculty of / Earth, Ocean and Atmospheric Sciences, Department of / Graduate
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Palynology and Palynofacies Analyses of the Gray Fossil Site, Eastern Tennessee: Their Role in Understanding the Basin-Fill HistoryZobaa, Mohamed K., Zavada, Michael S., Whitelaw, Michael J., Shunk, Aaron J., Oboh-Ikuenobe, Francisca E. 01 August 2011 (has links)
The Gray Fossil Site (GFS) includes multiple karst sub-basins that are filled with lacustrine sediments. Early paleontologic work on one of the sub-basins (GFS-2) indicates a late Miocene/early Pliocene age based on an assemblage of well-preserved vertebrate fossils. However, detailed palynological analysis of the 38.7. m deep GFS-1 core recovered from another sub-basin indicates an older age. The presence of Caryapollenites imparalis, C. inelegans and C. prodromus association suggests a Paleocene to Eocene age for the GFS-1 core section. This age is also supported by the absence of pollen of the Poaceae, the grass family that is not commonly present until the Neogene. Age constraints from palynologic data suggest that the GFS has a more complex basin-fill history than previously suspected, and that multiple depo-centers within the basin may have been periodically active through the Cenozoic. Palynofacies analysis of the GFS-1 core indicates that phytoclasts and opaques are the most abundant organic constituents and have diluted both the palynomorph population and amorphous organic matter. Two possible scenarios can account for this observation: 1) an oxidizing depositional paleoenvironment; and 2) a localized high flux of charcoal following wildfires and subsequent increased runoff.
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The Role of Clothing Fabrics as Passive Pollen Collectors in the North-Eastern United StatesZavada, Michael S., McGraw, Stephanie M., Miller, Melissa A. 01 December 2007 (has links)
The purpose of this investigation is to determine if clothing fabrics act as passive pollen collectors, and to determine if different fabrics vary with regard to the abundance and type of pollen trapped. Five of the most common fabrics in the United States (cotton, wool, polyester, silk and linen) were used to trap pollen. The pollen collecting apparatus was constructed of a 30 cm diameter circular needlepoint hoop, which vertically rotated freely, and was mounted on a dowel that was driven into the soil to chest height. Five pollen collectors, each with one of the five fabrics were placed at a collection site in rural, suburban, and urban habitats in Rhode Island for a 24 h period at weekly or biweekly intervals throughout 2002-2003. Pollen was washed from each of the fabrics and acetolysed. Total pollen per cm2 removed from each of the fabric types was estimated using a haemocytometer. The pollen types were identified, and 200 grains were counted to determine the relative abundance of the various pollen types recovered from the fabrics. Clothing fabrics act as passive pollen collectors and the flora recovered from the fabric represent the qualitative and quantitative components of the pollen rain for that specific day. There are quantitative differences among the relative abundance of pollen types from the three habitats (urban, suburban, and rural). Washing with water and a detergent eliminates a majority of the pollen from the fabrics.
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Palynomorph retention on clothing under differing conditionsRowell, Louise January 2009 (has links)
[Truncated abstract] Palynology has been used in a number of criminal cases where pollen and spores (palynomorphs) on clothing has featured as evidence. Pollen and spores are microscopic, generally morphologically unique to a plant genus and often species, resistant to decay, produced in large amounts and are components of soil. These unique features of pollen and spores make palynology a highly valuable forensic tool. Clothing is an excellent collector of pollen and spores as they become trapped in the fabric weave when clothing is brushed against flowering plants, comes into contact with dust, soil or air-borne pollen. Most forensic palynologists have found that palynomorphs from a crime scene may remain on clothing after washing or several days wear. No empirical research has been conducted on the retention of palynomorphs on clothing under differing conditions. Research of this kind is required to provide support for the future presentation and validation of palynological evidence in court. This project examined the relative retention of palynomorphs on clothing that had been worn during a simulated assault in a sheltered garden on the grounds of St George's College, Western Australia. Three replicate control soil samples each were collected from the actual assault scene and the whole garden to provide a baseline palynological profile for comparison to the experimental (Evidentiary) clothing samples. Forty pollen samples from the predominant species of plants in the garden and surrounds were collected, processed and databased as a reference for palynomorph identification. Standard T-shirts and jeans were chosen as the research clothing. During the simulated assault the knees of the jeans and the backs of the T-shirts came into abrasive contact with the soil of the garden for approximately one minute. The clothing then underwent three 'conditions' to simulate 'real life' situations. Three clothing sets were immediately collected after the assault (E1), three sets were worn for a period of three days after the assault (E2) and three sets were washed after the assault (E3). ... The Background clothing samples did not have a profile similar to the research garden but the profiles collected from each set reflected the areas to which they were worn. The number of palynomorphs per gram of garden soil ranged from thousands to tens-of-thousands of palynomorphs. The total number of palynomorphs collected by the E1 samples ranged from 100,000 to millions per clothing item. The E2 samples retained 1000's to tens-of-thousands of palynomorphs and the E3 samples retained 100's to 1000's of palynomorphs. The background clothing samples collected 1000's to tens-of-thousands of palynomorphs. These results confirm that jeans and T-shirts worn during an assault then worn for a period of days, or washed, will still contain pollen and spores characteristic of the assault area. This highlights the importance of investigating police enquiring where and for how long clothing of interest has been worn before and after an event, or if the clothing has been washed since the event. The results of this study will provide forensic palynologists with supportive data for future casework involving clothing.
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The ecology of some British podzol formationsDimbleby, G. W. January 1950 (has links)
No description available.
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PALEOGENE MIRELANDS OF THE UPPER MISSISSIPPI EMBAYMENT, WESTERN KENTUCKYO'Keefe, Jennifer Marie Klein 01 January 2008 (has links)
Detailed petrography, geochemistry, and palynology together describe the depositional environments and paleoecology of an abandoned meander-fill system in western Kentucky. Oriented block petrography reveals alternating clay-rich and attrinite-rich zones of variable thickness. Woody tissues, where present, do not show dessication features and deflation layers could not be identified. Overall, petrography is indicative of a topogenous mire. Mire palyno-assemblages are less diverse than assemblages reported from clays in the region. Castanea-Cupuliferoidaepollenites assemblages dominate the entire system and other tree pollen are common; fungal spores are relatively uncommon. Weighted statistical analyses reveal ecological groupings beyond this dominance and define botanical succession within the mire. The nearestliving- relative method for determining paleoclimate indicates temperate to warm temperate conditions during deposition. Palynology indicates a Claibornian stage, middle Eocene age for the deposit.
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THE IMPLICATIONS OF ATMOSPHERIC POLLEN RAIN FOR FOSSIL POLLEN PROFILES IN THE ARID SOUTHWEST (AEROBIOLOGY, PALAEOBOTANY, TAPHONOMY, PRESERVATION).O'ROURKE, MARY KAY. January 1986 (has links)
I compared atmospheric and soil pollen values to determine taphonomic influences on pollen in Southwestern soils. Burkard traps sampled atmospheric pollen for six years from multiple sites in Tucson, Arizona. Tauber and soil samples were collected for two years at Tumamoc Hill (Tucson). Morus, Ambrosia, Gramineae, and Chenopodiaceae-Amaranthus characterize Tucson's airborne pollen. Artemisia, Garrya and summer Pinus pollen are transported from the mountains. Annual pollen capture is similar between Burkard and Tauber samplers. Atmospheric pollen is seasonally variable; annual variability is low. Spatial variability among sites is low. Pollen concentrations vary widely among sites, but taxonomic composition remains constant. Reentrained soil pollen comprises 11% of the airborne pollen. Gramineae and Chenopodiaceae-Amaranthus pollen comprise 90% of the reentrained pollen. Pollen reentrainment varies seasonally. High maximum and minimum temperatures, low dew point and moderate wind speeds are associated with maximum atmospheric pollen concentrations. Winds preceding summer storms cause increased pollen concentrations. Deterioration characterizes pollen from soils. Chenopodiaceae-Amaranthus, Ambrosia, Other Compositae and Graminear are commonly found; Morus is rarely found. Pinus, Sphaeralcea, Boerhaavia and Kallstroemia are present in low numbers. These taxa have thick pollen walls, and they resist destruction. Seasonally collected soil samples have similar pollen spectra. Seasonal airborne pollen variability does not affect the soil pollen spectra. Inoculated soil pollen is well preserved, but pollen is lost rapidly. After one year, pollen concentrations approached background levels for seven of the eight pollen taxa tested. Solidago remained an order of magnitude higher. Pollen morphology may play a role in differential pollen loss. Pollen from the inoculated plots is lost through post-mortem transport. Pollen in soils is time-averaged and exhibits little temporal variability. The average airborne pollen spectra differs from the pollen in the soil. Soil pollen was degraded; inoculated plot pollen was well preserved. I conclude airborne pollen contributes little to the soil pollen of Tumamoc Hill. The soil pollen spectra is affected by selective- or non-deposition of airborne pollen (e.g. Morus), differential pollen destruction, and differential post mortem transport.
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"Hautes terres" : l'anthropisation des monts d’Aubrac et du Lévezou (Massif Central, France) durant l’holocène : approche palynologique des dynamiques socio-environnementales en moyenne montagne / "Highlands" : anthropisation of Aubrac and Levezou (Massif Central, France) during Holocene : palynological approach of socio-environmental dynamics in a middle mountain rangeFaure, Élodie 17 September 2012 (has links)
L’étude des interactions sociétés-milieux sur la longue durée, à l’origine de la construction des paysages de l’Aubrac et du Lévezou, a été menée à partir d’une démarche largement pluridisciplinaire dans laquelle la palynologie constitue l’outil principal. La constitution d’un référentiel actuel a conduit, dans un premier temps, à discriminer les principaux taxons polliniques représentatifs des activités humaines et d’en préciser la représentativité spatiale et fonctionnelle. L’étude multi-proxy de six séquences sédimentaires, étayées par 24 datations radiocarbones, a, dans second temps, permis de retracer l’histoire de la végétation et de l’anthropisation, notamment par l’identification des rythmes, des seuils et des ruptures durant l’Holocène. L’évolution des paysages en lien avec le développement des déboisements et des activités agricoles a pu être appréhendée à une échelle locale grâce aux apports combinés des pollens, des macrocharbons, des microfossiles non polliniques, de la confrontation avec les données archéologiques disponibles et de l’examen des sources archivistiques. Les premiers indices tangibles de fréquentation du massif de l’Aubrac apparaissent au cours du Néolithique moyen et les pratiques semblent se généraliser au Néolithique final sur l’Aubrac et le Lévezou. L’âge du Fer et le début de l’Antiquité marquent les premiers déboisements importants sur le plateau de l’Aubrac, concomitants d’une hausse de la pression agropastorale observée dans tous les sites. Enfin, les périodes médiévales et modernes contribuent à ancrer les formes du paysage esquissées aux époques plus anciennes. L’ensemble de ces dynamiques suggère avant tout l’importance des variabilités territoriales qui renvoient à des modes d’occupation temporaires jusqu’à l’âge du Bronze et à une grande mobilité des pratiques. Ces territoires présentent également des tendances communes qui répondent pour une part aux grandes trajectoires de colonisation des espaces montagnards. A l’examen de ces dynamiques d’anthropisation, le forçage climatique ne semble pas avoir été un facteur limitant et pourrait constituer un stimulus positif favorisant le développement de nouvelles stratégies adaptatives. / Based upon a multidisciplinary approach centered on palynology, the aim of our study was to better understand the long-term interaction in human/vegetation processes in the Aubrac and Levezou mountainous regions (Massif Central, France). In a first step, the relationships between present pollen deposition, vegetation and land-uses have been studied using a comparative approach. The main pollen taxa representative of human activities have been isolated and their spatial and functional representativeness have been assessed. Secondly, six sedimentary records, supported by 24 radiocarbon dates, have been studied with a multi-proxy approach combining pollen, macro charcoals, non-pollen palynomorphs, archeological and historical data. The analysis has allowed us to characterize vegetation history and local human impact on the landscape, in particular rhythms, breaks and thresholds concerning anthropisation’s dynamics According to our analysis, the first signs of human impact on the vegetation appear in Aubrac during the middle Neolithic period, while evidence of human activities seem to extent during the Late Neolithic. The Iron Age and early Antiquity periods are characterized by large scale deforestation correlated to the increase of the agro-pastoral pressure. Our analysis further suggests that the medieval and modern periods consolidate the types of landscape that have been created in earlier periods. The dynamics that have been highlighted in this study suggest an important degree of spatial variability of land use. The analyzed territories present common trends that correspond to colonization trajectories generally encountered in mountain areas. Relative to anthropisation’s dynamics, climate forcing seems to have not been a limiting factor for human settlements and may even have been a positive stimulus promoting the development of new adaptive land use strategies.
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