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Undersökning av miljöpåverkan från järnsand i en sedimentstudie i Inre-viken, Skellefteå / Using sedimentary records to investigate iron sand’s environmental impact in Inre-viken, Skellefteå (English)Rikard, Haldebo January 2015 (has links)
With rapidly urbanizing societies, waste management needs attention. In 2008, EUs Waste Framework Directive (WFD) set new concepts, like reducing usage of natural materials. Thus, the interest for alternative materials increased. In Skellefteå, since the 1970’s, iron sand has often substituted natural gravel in road construction. But, today stricter regulations might forbid iron sand for further use. The issue is whether leachate from iron sand causes heavy metal pollution or not. This thesis tried to provide more knowledge into iron sand’s environmental impact. In order to investigate this, a sediment sample (<53 cm deep) collected in Inre-viken, a lake 50m from a road with iron sand, were analyzed for Zn, Pb and Cu concentrations. Enrichment factor (EF), national benchmarks, and reference data were used to evaluate anthropogenic impact and age-determine the sediment. The results showed: (1) Inre-viken has elevated heavy metal levels compared to pre-industrial levels, with highest Cu (133 mg/kg) and Zn(204 mg/kg) concentrations found in the surface layer. (2) Zn and Cu showed an increase between 41-0 cm depth (1970-2015), but only Cu reaches high concentrations, while Zn and Pb range between low to very low concentrations. (3) The metal enrichment is low compared to the reference lake. The findings show that there are elevated levels in Inre-viken compared to pre-industrial levels. However, identifying the main source of pollution is difficult, because many pollution sources exist in the area. To determine if iron sand is the culprit, further studies are necessary.
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An analysis of fracture systems, lithologic character and kinematic history of Paleozoic rock formations in a portion of southeastern IndianaKeene, David G. January 1989 (has links)
This is an analysis of fractures occurring within the Paloezoic sedimentary rocks in a portion of southeastern Indiana. Fifteen hundred seventy-two fractures were used in analysis of distribution, orientation, pervasiveness, persistence, and intensity. The data collected is representative of eight counties and seventeen different collection sites.All fracture data were given an associated numerical value identifying each variable used for analysis and recorded into computer data files. A computer program was used for statistical analysis and construction of equal area nets which graphically displayed the distribution of variables. The compilation of the fracture data allowed for close interpretative analyses of variables and correlation of the orientation and distribution of the fractures within the study area.This study revealed that two orthogonal fracture systems exist in southeastern Indiana. The fracture set containing the largest percentage of those measured is oriented N11W with its compliment oriented N73W. The orientation of the second largest fracture set is N8E with its compliment oriented N82°W.The effects of the tectonic history as well as contemporary stress on the area are discussed relative to their effects on the overall distribution of fracture sets.Evidence is presented to substantiate a reactivation of the Cincinnati Arch as indicated in the Devonian-Mississippian lithologic units from data collected in the southeastern portion of the study area. Fracture data correlating to these units displays a rotation of the major fracture set maxima 90w. This data is supported by radiometric dates from the Belfast member of the Brassfield Limestone in which Laskouski, et.al., correlated a reactivation of the arch.Also within this study are lithologic descriptions of all the Paleozoic formations used for data collection. These descriptions were developed over a three year period from extensive field observation.A map of the study area is presented displaying the distribution and orientation of the fractures recorded at each data collection site. / Department of Geology
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Architecture, geodynamic evolution and sedimentary filling of the levant basin : a 3D quantitative approach based on seismic dataHawie, Nicolas 03 February 2014 (has links) (PDF)
Sedimentological and biostratigraphic investigations onshore Lebanon coupled with 2D offshore reflection seismic data allowed proposing a new Mesozoic-Present tectono-stratigraphic framework for the northern Levant Margin and Basin. The seismic interpretation supported by in-depth facies analysis permitted to depict the potential depositional environments offshore Lebanon as no well has yet been drilled. The Levant region has been affected by successive geodynamic events that modified the architecture of its margin and basin from a Late Triassic to Middle Jurassic rift into a Late Cretaceous subduction followed by collision and Miocene-Present strike slip motion. The interplay between major geodynamic events as well as sea level fluctuations impacted on the sedimentary infill of the basin. During Jurassic and Cretaceous, the Levant Margin is dominated by the aggradation of a carbonate platform while deepwater mixed-systems prevailed in the basin during the Oligo-Miocene, three major sedimentary pathways are expected to drive important quantities of clastic material into the Levant Basin: (1) canyons along the Levant Margin, (2) the Latakia region (coastlal Syria) and (3) the Nile Deep sea cone. Regional drainage system analysis was performed to estimate the contribution of the different sediment sources to the infill of the basin. A numerical stratigraphic forward model, Dionisos, was used to test the Middle-Late Miocene source-to-sink scenarios permitting to better assess the plausibility of the expected sedimentary volumes for each source through a comparison with actual drainage systems
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Sedimentological and palaeoenvironmental studies in the Broadford Beds (Hettangian-Sinemurian) of north-west ScotlandAmiri-Garroussi, Kourosh January 1978 (has links)
Planorbis to Turneri Zone sedimentary rocks were studied at outcrops on Skye, Raasay, Applecross, Ardnamurchan, Morvern and Mull. A proposed lithostratigraphy includes two Groups, four Formations and seventeen Members. Increased faunal diversity in Mull and Skye reflects environmental stability during the Angulata and Semicostatum Zones; low diversity in the Bucklandi and Turneri Zones signifies lower stability. Species abundance in Mull and their decrease in Skye during Angulata-Bucklandi Zone times signifies a northward increase in environmental instability. Smectites are present in the Planorbis-Bucklandi Zone shales. The Semicostatum-Turneri Zones are composed of non expanding clays; the smectite formed by erosion of previously exposed alkaline igneous rocks under warm, alkaline, low rainfall conditions. Progressive transgression covered the source area and a change to more acidic conditions with higher rainfall also promoted the formation of "ironstones" and chlorites. The Angulata and Bucklandi Zones comprise bioclastic, oolitic, carbonate and siliciclastic sediments signifying shallow marginal marine semi-enclosed basins. Thin laterally impersistent beds of coarse,poorly sorted pebbles signify an unstable hinterland; during the Semicostatum and Turneri Zones fully marine conditions were established. Ferruginous beds are oolitic in Skye. They probably formed as "mud balls" and due to acid leaching of feldspars. Phosphatic nodules are calciumhydroxyapatite. The limestone/shale "rhythms" are explained by a combined primary and diagenetic origin. The limestones consist of low-Mg calcite Both ferroan and non ferroan calcite are present. Tectonic stresses and diagenesis deformed crystals and formed veins. Sr<sup>+2</sup> values show a decline as the carbonate fraction increases. Three different ranges are distinguished for three facies and ages. Sr concentration is bimodal and probably inherited from the original sediments. The northern and southern basins evolved separately, sedimentation was controlled by differential tilting, uplift and subsidence. Palaeoslopes were gentle, to the west-northwest and south-southwest. Local topography (e.g. Central Strath High) modified the slopes; no movement occurred along the main faults of the area. Sedimentation relates to the "taphrogenic rifting stage" proposed for the North Sea Mesozoic.
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Seismic and well test analysis methods to characterise fluvially deposited reservoir elementsBarens, Leonardus Maria January 2001 (has links)
No description available.
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Sequence Stratigraphic Architecture Of Mut Basin Along Ramp To Reefal Margin Transition And Its Diagenetic ImprintDerman, Hasan Armasan 01 January 2004 (has links) (PDF)
The whole Mediterranean was a site of carbonate deposition during Miocene. Unlike other Miocene basins in the Mediteranean, the importance of Mut Basin lies in its tectonically undisturbed nature that provides excellent
exposures to study sequence stratigraphic architecture and carbonate sedimentology. Opening of Mut Basin began during Oligocene / carbonate deposition started during Early Miocene. The pre-Miocene rocks are characterized by (from bottom to top), 1. ophiolites and Mesozoic limestones, 2. Eocene lacustrine limestones, 3. Burdigalian fluvial sandstones and conglomerates. The carbonate deposition began in Miocene, settling on the preexisting topography. Carbonates have been deposited in a ramp setting, where several sequences formed. The ramp was partly subaerially exposed during Early Miocene due to relative sea level fall / however, no significant lowstand
deposits were developed. The subsequent sea level rise caused transgressive deposits to overlie this ramp sequence. The patch reefs on this ramp exhibit a keep-up type depositional setting. As the transgression continued,
the basin topography controlled the type of depositional setting. Hence, a transition from ramp to reefal margin type setting occurred. In landward direction the topographically low areas became back reef lagoonal part of this reefal margin. A mature reefal environment formed during highstand times, which is characterized by a rich coral fauna / algal flora in the basinward side. Some of the patch reefs of the ramp transformed into pinnacle reefs. Diagenetic alterations are mostly related to duration and degree of sea level
fall, and therefore related to sequence boundaries.
The Miocene carbonates in the study area consist of six sequences which may be used for correlation with other Miocene carbonates of the Mediterranean region.
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Sedimentary evolution, hydrogeology and geochemistry of a back-barrier sand island : Toorbul, Southeast QueenslandHodgkinson, Jonathan January 2008 (has links)
Small back-barrier sand islands are poorly known in terms of hydrogeology and have been overlooked in more extensive studies of coastal groundwater systems that include larger barrier island complexes. This study employs a three-fold sequential approach to aquifer characterisation in a back-barrier sand island. A three-dimensional stratigraphic model forms the foundation framework, being derived from a multidisciplinary approach to sedimentary analysis and the construction of a depositional chronology. A conceptual hydrostratigraphic model is formulated based on the translation of sedimentary facies to hydrofacies, combined with density dependent flow calculations and tidal oscillation measurements. Groundwater hydrochemical data and mineral geochemistry are integrated with the resulting hydrogeological model to examine water-rock interaction and solute transport mechanisms. The study area is Toorbul Island, a small back-barrier sand mass of ~5 km2 with a maximum surface elevation of ~3.5 m AHD, located in the Pumicestone Passage of Southeast Queensland. The island hosts a dual aquifer system consisting of an unconfined island freshwater lens, underlain by a semi-confined palaeovalley-fill aquifer. Groundwater in the semi-confined aquifer is hyper-saline, carrying high concentrations of dissolved metals, with iron, in particular, ranging from 40 to < 200 mg l-1. This is of significant interest for both human health and environmental management, because iron is an important nutrient source for toxic algal bacteria such as Lyngbya majuscula. Conceptual modelling demonstrates that iron oxides and hydroxides are the main source of iron in the semi-confined aquifer, with a contribution from ferruginous chlorite dissolution. Aqueous manganese and a proportion of the aqueous iron are derived from the dissolution of manganoan ilmenite. Ferric iron minerals also contribute a significant proportion of dissolved iron in the deeper regions of the unconfined aquifer. Aqueous iron in the shallow unconfined groundwater is limited by iron sulphides, which also regulate acidity and indirectly limit dissolved aluminium concentrations. Groundwater redox state governed by seasonal climatic fluxes is the most significant control on iron-bearing mineral phase stability. Transport of dissolved metals to the surrounding estuary and the adjacent barrier island groundwater system is limited by the rate of ion diffusion across transition zone boundaries. The overall conclusions derived from this research show that back-barrier islands should be evaluated as discrete hydrogeological entities. The stratigraphic complexity that may be apparent within these island landforms should not be underestimated and the model domain should not necessarily be treated as a homogeneous system. This complexity is exemplified by the relationship between the upper and lower aquifers on Toorbul Island and the associated distribution of groundwater compositional heterogeneity. The complex stratigraphy within the sedimentary pile is derived from the presence of a sub-surface palaeovalley and the sedimentary response to changing sea-level over time. Considering the current widespread distribution of estuarine systems, complex hydrogeology as exhibited by Toobul Island, may be common in many small back-barrier island groundwater systems. The aquifer characteristics and their influence on solute transport and delivery can have significant ramifications for the exploitation of the adjacent coastal plain and barrier island aquifers. The potential influence on the latter is of particular concern due to the pressure imposed on potable groundwater supplies by increasing population densities in coastal areas.
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Tertiary uplift and its implications for the tectonic evolution of sedimentary basins, offshore south-west United Kingdom / Robert John Menpes.Menpes, Robert January 1997 (has links)
Copies of author's previously published works inserted. / Bibliography: p. 157-165. / ix, 165 p. : ill. (chiefly col.), maps ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Sonic velocities from the Danian Chalk, Upper Cretaceous Chalk, Lower Cretaceous Greensand/Gault Clay, Lower Cretaceous Wealden, Upper Jurassic mudstones, Triassic Mercia Mudstone, and Triassic Sherwood Sandstone have been used to quantify apparent exhumation in the Celtic Sea/South Western Approaches. / Thesis (Ph.D.)--University of Adelaide, Dept. of Geology and Geophysics, 1998
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A petrophysical study on the influence of effective stress and fluid saturation on acoustic velocities in sandstones / Abbas Khaksar.Khaksar, Abbas January 1999 (has links)
Bibliography: leaves 147-157. / xiii, 157, [70] leaves, [16] leaves of plates : ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, National Centre for Petroleum Geology and Geophysics, 1999
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Sedimentology of the Ouldburra Formation (Early Cambrian), northeastern Officer Basin /Dunster, John N. January 1987 (has links) (PDF)
Thesis (M. Sc.)--University of Adelaide, 1987. / Col. folded map in pocket of v. 1. Includes bibliographical references.
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