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1
Radeff, Giuditta. "Geohistory of the Central Anatolian Plateau southern margin (southern Turkey)." Phd thesis, Universität Potsdam, 2014. http://opus.kobv.de/ubp/volltexte/2014/7186/.
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The Adana Basin of southern Turkey, situated at the SE margin of the Central Anatolian Plateau is ideally located to record Neogene topographic and tectonic changes in the easternmost Mediterranean realm. Using industry seismic reflection data we correlate 34 seismic profiles with corresponding exposed units in the Adana Basin. The time-depth conversion of the interpreted seismic profiles allows us to reconstruct the subsidence curve of the Adana Basin and to outline the occurrence of a major increase in both subsidence and sedimentation rates at 5.45 – 5.33 Ma, leading to the deposition of almost 1500 km3 of conglomerates and marls. Our provenance analysis of the conglomerates reveals that most of the sediment is derived from and north of the SE margin of the Central Anatolian Plateau. A comparison of these results with the composition of recent conglomerates and the present drainage basins indicates major changes between late Messinian and present-day source areas. We suggest that these changes in source areas result of uplift and ensuing erosion of the SE margin of the plateau. This hypothesis is supported by the comparison of the Adana Basin subsidence curve with the subsidence curve of the Mut Basin, a mainly Neogene basin located on top of the Central Anatolian Plateau southern margin, showing that the Adana Basin subsidence event is coeval with an uplift episode of the plateau southern margin. The collection of several fault measurements in the Adana region show different deformation styles for the NW and SE margins of the Adana Basin. The weakly seismic NW portion of the basin is characterized by extensional and transtensional structures cutting Neogene deposits, likely accomodating the differential uplift occurring between the basin and the SE margin of the plateau. We interpret the tectonic evolution of the southern flank of the Central Anatolian Plateau and the coeval subsidence and sedimentation in the Adana Basin to be related to deep lithospheric processes, particularly lithospheric delamination and slab break-off.Il Bacino di Adana (Turchia meridionale) é situato in posizione esterna rispetto al margine sud-orientale del plateau anatolico centrale. Il bacino risulta ubicato in posizione strategica per registrare i principali cambiamenti della topografia e dell’assetto tettonico avvenuti durante il Neogene nel Mediterraneo orientale. Utilizzando dati sismici provenienti dall’industria petrolifera abbiamo correlato 34 profili sismici con le unitá corrispondenti affioranti nel Bacino di Adana. La conversione da tempi a profonditá dei profili sismici interpretati ci ha permesso di ricostruire la curva di subsidenza del Bacino di Adana e di individuare un evento caratterizato da un importante aumento della subsidenza associato ad un considerevole incremento del tasso di sedimentazione. Questo evento, avvenuto tra 5.45 e 5.33 Ma ha portato alla deposizione di quasi 1500 km3 di conglomerati e marne. La nostra analisi di provenienza della porzione conglomeratica mostra che la maggior parte del sedimento proviene dal margine sud-orientale del plateau anatolico centrale e dalle aree situate a nord di questo. La comparazione di questi risultati con la composizione litologica di conglomerati recenti e con le litologie affioranti nei bacini di drenaggio attuali mostra cambiamenti rilevanti tra le aree di provenienza del sedimento Messiniane e quelle attuali. Riteniamo che questi cambiamenti nelle aree sorgente siano il risultato del sollevamento e della successiva erosione del margine sud-orientale del plateau anatolico centrale. Questa ipotesi é supportata dal confronto delle curve di subsidenza del Bacino di Adana e del Bacino di Mut, un bacino principalmente neogenico situato sulla sommitá del margine meridionale del plateau. La comparazione delle due curve di subsidenza mostra che l’evento di forte subsidenza del Bacino di Adana é coevo ad un episodio di sollevamento del margine meridionale del plateau anatolico centrale. La raccolta di un fitto dataset strutturale acquisito nella regione di Adana mostra differenti stili deformativi per i margini nord-occidentale e sud-orientale del bacino. La porzione nord-occidentale del bacino, debolmente sismica, é caratterizzata da strutture estensionali e transtensive che tagliano I depositi neogenici, verosimilmente accomodando il sollevamento differenziale tra il bacino e il margine sud-orientale del plateau. Riteniamo che l’evoluzione tettonica del margine meridionale del plateau anatolico centrale e la contemporanea subsidenza e sedimentazione nel Bacino di Adana sia da ricondurre a processi litosferici profondi, in particolar modo delaminazione litosferica e slab break-off.
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Radeff, Giuditta [Verfasser], and Domenico [Akademischer Betreuer] Cosentino. "Geohistory of the Central Anatolian Plateau southern margin (southern Turkey) / Giuditta Radeff. Betreuer: Domenico Cosentino." Potsdam : Universitätsbibliothek der Universität Potsdam, 2014. http://d-nb.info/1058741004/34.
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Bergh, Eugene. "Neogene to quaternary foraminifera from the western margin of southern Africa." Doctoral thesis, Faculty of Science, 2019. http://hdl.handle.net/11427/30436.
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The western margin of southern Africa underwent major palaeoceanographic changes since the initiation of the Benguela Upwelling System during the Neogene. Microfossils in marine sediments provide key proxies in our understanding of how the margin evolved. Fossil shells (tests) of foraminifera (singlecelled protists) from twenty cores from the Namibian shelf (199 to 309 m water depth) and three cores from the western slope (874 to 3631 m water depth) of South Africa were studied to determine the middle Miocene to Quaternary stratigraphy, palaeoenvironment and palaeoceanography of the western margin of southern Africa. Cores from the Namibian shelf recovered middle Miocene calcareous mud in erosional contact with overlying Pliocene to Pleistocene phosphatic sediments. Strontium isotope stratigraphy and planktic foraminifera biostratigraphy provide age control of the Namibian shelf sediments. The planktic indicator species Globoquadrina dehsicens and Globigerinoides bisphericus support strontium isotope stratigraphy results for the olive-green mud unit of the northern Namibian shelf indicating an age of 16 to 14 Ma, and the overlying Plio-Pleistocene age of the phosphorite-rich unit supported by planktic indicator species Globorotalia truncatulinoides and Globorotalia (Globoconella) inflata. Middle Miocene foraminifera reflect a warmer, oligotrophic, subtropical, deeper environmental setting in contrast to the shallower depositional environment, cooler conditions and a eutrophic bottom water setting indicated by Pleistocene foraminifera in the phosphatic units. The palaeoenvironment on the Namibian shelf was progressively shoaling during the Pleistocene as sea level amplitudes increased. An Uvigerina spp.- dominated association occurs in deeper shelf deposits dated to the early Pleistocene and the Ammonia beccarii association occurs in shallower shelf deposits of the late Pleistocene to Holocene. The planktic and benthic foraminiferal stable oxygen isotope records, colour reflectance (L*) and non-carbonate mineral counts provide age control on cores from the western slope of South Africa, whose records extend to just beyond Glacial Termination (GT) II. Sediment and benthic foraminiferal accumulation rates were higher during interglacial periods and lower during glacial periods. The major planktic species in the slope cores include Globorotalia (Globoconella) inflata, Globigerina bulloides and Neogloboquadrina incompta. Principal component analysis (PCA) reveals that the major factors influencing planktic foraminiferal abundances are upwelling intensity, the penetration of colder waters during glacial periods and the inflow of subtropical waters from the South Indian Ocean during interglacial periods. The major benthic species in the slope cores include Uvigerina peregrina, Uvigerina hispidocostata and Cibicidoides wuellerstorfi indicating the delivery of organic matter and oxygen availability to have the largest influence on the benthic foraminiferal faunal composition. Uvigerina spp. on the slope show increased relative abundances during periods of lower oxygen conditions. Bottom water masses identified by Nd (neodymium isotopic compositions) values recorded by foraminifera, along with the stable carbon isotope composition and abundance of the benthic foraminifer C. wuellerstorfi indicate shifts from Southern Component Water to North Atlantic Deep Water during GT II and I. Variation in Nd values in an upper slope core (874 m water depth) indicate Antarctic Intermediate Water (AAIW) influence was stronger during glacial periods compared to interglacial periods.
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Mohamed, Hwedi Abdulsalam. "The Holocene palaeoenvironments of the rift margin in Southern Jordan (Wadi Faynan)." Thesis, University of Huddersfield, 2000. http://eprints.hud.ac.uk/id/eprint/4871/.
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Smart, Susannah Mary. "Asphaltites from the Southern Australian margin : submarine oil seeps or maritime artefacts? /." Adelaide, 1999. http://web4.library.adelaide.edu.au/theses/09SB/09sbs636.pdf.
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Hall, Lisa Sarah. "Cenozoic deformation at the southern end of the Hikurangi Margin, New Zealand." Thesis, University of Oxford, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.403720.
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Ball, Philip Joseph. "Break-up history and evolution of the southern passive margin of Australia." Thesis, Royal Holloway, University of London, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.421466.
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Despite intensive studies, the process of continental break-up remains enigmatic, in large part because the record of break-up is located in deepwater regions. Existing models are based on a limited academic data set. This study aims to add to our data base of weakly magmatic margins worldwide through a study of the continental breakup between Australia and Antarctica. Earlier studies did not examine the conjugate margins in tandem, and the deep water setting hampered attempts to establish a regional chrono-stratigraphic framework. Furthermore, existing reconnaissance seismic reflection and sparse refraction data provided only a 2-D view of small areas of the >1800 km-long margin. Thus, there was little consensus in interpretations of the evolution of the southern margin of Australia, as well as models for break-up. This study aims to (i) establish the structural variability and framework of the Australian and Antarctic margins; (ii) determine the along-axis segmentation of the margin and its relation to faulting and seafloor spreading processes; (iii) determine the sediment thickness and crustal thickness in 3-D; (iv) reconcile the position of the ocean-continent boundary derived from magnetic anomaly and seismic interpretations. These results are then interpreted in light of existing data from the conjugate Antarctic margin to propose a new model for continental break-up between the Australo-Antarctic conjugate margins. I analyse a new compilation of merged onshore, offshore, and satellite gravity data, as well as seismic reflection, magnetic, and well data from the Great Australian Bight, southern Australia. Estimates of the 3-D crustal thickness, depth to basement, the position and nature of the continent-ocean-boundary, and interpretations of major basement-involved structures were derived from analyses of terrain-corrected Bouguer gravity data. The gravity interpretations are constrained with seismic reflection, refraction and magnetic data. The potential field modelling within this thesis has been conducted using Geosoft and in-house software. Continental break-up between Australia and Antarctica occurred oblique to the identified major basement terrains and pre-existing structures. Two spatially and temporally discrete rift events are identified along the Australian southern margin. Integrated structural patterns are used to suggest that the first rift phase (165-115 Ma)developed within two discrete overlapping rift systems; the W-E trending Bight-Wilkes rift (165-135 Ma) and the NW-SE trending Otway-Adelie (145-115 Ma) rift. Each rift system is interpreted to terminate at or near to the boundary of the mechanically strong Gawler craton, suggesting that the craton served as an obstacle to rift propagation The second identified rift phase (92-50 Ma) corresponds with the localization of strain to a narrow rift zone within the interpreted COT zone. Within the transitional rift basement faults are observed to young both oceanwards and to the SE indicating that rifting processes were diachronous within the transitional rift itself. Concomitant with the transitional rift, complex and anomalously high density, high susceptibility structural highs are observed. The basement highs either have a close relationship to basement-involved faults or some appear to be intrusive within the transitional crust. These anomalous basement features are tentatively interpreted to be mafic bodies. By analogy to other non-volcanic margins (e.g. Whitmarsh et al. 2000; Beslier et al. 2004) it is likely that they represent either exhumed upper mantle, serpentinite, or lower crustal rocks or partial melt products derived from the underlying upper mantle. Plate reconstructions of the continent-ocean-transition [COB] indicate that break-up initiated within the centre of the Australo-Antarctic plate at -83 to 79 Ma. The reconstructions of the newly defined, gravity and seismic, COB's across the Australian and Antarctic margins reveal large degrees of overlap casting doubts upon the validity of the existing poles of rotation to replicate the early kinematics of the Australian and Antarctic margins. For the Otway-Adelie Sector the asymmetry of break-up, the delayed onset of oceanic accretion and the large overlaps in reconstructions may be explained with a two phase oblique-shear model. It is proposed, therefore, that rifting and break-up between Australia and Antarctica occurred initially within a NW-SE regional plate divergence which switched to N-S at -61 Ma (post-c27y). Break-up or rather the onset of rapid oceanic accretion processes offshore the northern sector ofthe Otway-Adelie rift is inferred to have initiated by -53 Ma. The integration of the results presented within this thesis has been used to develop a new break-up model for Australia and Antarctica. These results provide new insights into continental break-up within weakly magmatic rift zones, as well as constraints for heat flow modeling and hydrocarbon prospectivity studies.
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Wolfenden, Ellen. "Evolution of the southern Red Sea Rift : birth of a magnetic margin." Thesis, Royal Holloway, University of London, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.405194.
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Agurto, Detzel Hans. "Seismotectonics of the southern subduction Chilean margin revealed by recent aftershock sequences." Thesis, University of Liverpool, 2012. http://livrepository.liverpool.ac.uk/8553/.
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Subduction margins, as in the case of south-central Chile, are active seismotectonic environments and locus of the world largest earthquakes. In this thesis, two segments of the south-central Chilean subduction margin are studied: (A) the southernmost portion, at the termination of the Nazca-South America convergence (~46ºS), and (B) the segment located between 34º-38ºS, where the Mw 8.8 Maule Earthquake took place in 2010. Analysis of data from a local seismic network deployed in 2004-2005 in area A, indicates low levels of background seismicity with magnitudes ranging 0-3.4 Ml. The seismicity corresponds to shallow crustal events, mostly occurring within the upper 10 km. A third of the seismicity is associated to volcanic activity present in the area, while scarce seismicity is associated with a large strike-slip fault, the Liquiñe-Ofqui Fault System (LOFS), that intersects the region along the arc in a N-S-trend. In 2007, this region was affected by a seismic sequence with a peak of activity associated with a Mw 6.2 earthquake in April that year. A local seismic network was deployed after this main event in order to study its sequence of aftershocks, which provided a unique opportunity to characterise seismotectonically this area that usually lacks intermediate magnitude seismicity, including the calculation of a new local velocity model, accurate aftershock locations and computation of focal mechanisms. The results show P-wave velocities of ~5 km/s for the upper 5 km in accordance with the geology of the area, and low S-wave velocities for the upper 3 km of crust due to rock fracturing and the presence of fluids. An average Vp/Vs ratio of 1.76 was calculated for the region. The alignment of most of the aftershocks within the LOFS plus obtained focal mechanisms, indicate that this sequence had tectonic origin related to the re-activation of the LOFS. Further, a maximum seismogenic depth of about 15 km was determined for the entire region. Regarding area B, affected by a large megathrust earthquake in 2010, the study of moment tensor solutions for the sequence of aftershocks provided new insight into the distribution of postseismic activity relative to co-seismic slip and the release of seismic afterslip. Thrust aftershocks dominate the postseismic activity, but also normal faulting was detected in the outer-rise area and in the overriding plate near the coastline. The largest seismically released afterslip is located between the two main patches of co-seismic slip. Large aftershocks (M>4) occur along the megathrust interface, in zones of intermediate co-seismic slip associated to stress introduced on dislocation tips with high co-seismic slip contrast. On the other hand, smaller events (M<4) tend to occur in areas of large co-seismic slip, and might indicate a more diffuse distribution within the damage zone of the megathrust plane. It is likely that these smaller events are associated to secondary processes (fluid release, re-activation of secondary structures). Although belonging to the same subduction margin, the seismotectonics and earthquake patterns of the two areas investigated here show different underlying tectonic regimes. For the northern area, locus of the 2010 Mw 8.8 Chile earthquake, inter-plate thrust seismicity is dominant both in term of quantity of events and moment release. Conversely, the southern area presents only shallow intra-plate crustal seismicity mainly occurring in the arc, where Quaternary volcanism and the LOFS are present.
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McGowan, James Andrew. "Hercynian transpressional tectonics at the southern margin of the Central Iberian Zone, western Spain." Thesis, University of Southampton, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.358641.
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Board, Warwick Stuart. "Fluid evolution and mineralising potential in the outer margin of the southern Gariep Belt." Master's thesis, University of Cape Town, 1998. http://hdl.handle.net/11427/9647.
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Bibliography: leaves 94-102.Fluid inclusion analyses of quartz veins of various generations from the outer margin of the southern Gariep Belt reveal the presence of two chemically distinct fluid populations: the pre-orogenic, rift-related Rosh Pinah ore-forming fluid and the orogenic fluids. The oreforming fluid is more saline and chemically more complex than the orogenic fluids, probably representing hot, chemically evolved hypersaline brines induced by rift-related magmatism. Four generations (D₁/D₂, D₃, D₄ and D₅) of orogenic veins are recognised on the basis of their structural relationships. The orogenic fluids are chemically similar, dominantly aqueous and generally of moderate to low salinities (<10 wt% NaCleq), with the few higher salinity estimates (10-16 wt% NaCleq) being attributed to the interaction of some of the orogenic fluids with evaporitic horizons. A trend of decreasing temperature with a decrease in age (D₄> D₁/D₂>D₃>D₅) is developed within the orogenic fluids, with the exception of those fluids related to the emplacement of the Kuboos Pluton, which yielded the highest temperatures. The D₁/D₂ fluids from the northern and Vanrhynsdorp areas were hotter than the fluids from the central area, whereas the D₃ and D₅ fluids exhibit no apparent temperature variation as a function of area. D₄ fluids show a decrease in temperature further away from the pluton. Estimates of the maximum metamorphic pressure recorded in the outer margin of the belt have been further constrained, using microthermometry results in conjunction with mineral assemblages, to 2.9-3.6 kbar, 2.9-3.1 kbar and 1.8-3.1 kbar for the northern, central and Vanrhynsdorp areas, respectively. Field observations and fluid inclusion analyses suggest channeled fluid flow on a regional rather than on an intra-formational scale, even though a rock-buffered system is suggested by oxygen isotope results. A different, largely rock-dominated fluid system was developed within the relatively impermeable carbonate units compared with the fluid system developed within the rest of the outer margin of the belt. The D₁/D₂ fluids probably represent circulating formation and metamorphic waters that were advectively forced out of the orogen and into the foreland, whereas channeled meteoric fluid flow most likely dominated during the transtensive phase of the orogeny. The D₄ fluids probably contain a magmatic component, in addition to the meteoric component. Comparisons between the ore-forming fluid and the orogenic fluids indicate that the latter have neither the required salinities, nor the required chemistry necessary in order to transport sufficient metals to produce a massive sulphide deposit the size of Rosh Pinah. The chemistry of the orogenic fluids are, however, similar to those associated with gold remobilisation and as such the potential for gold mineralisation related to these orogenic fluids should not be ruled out. Base metal sulphide exploration within the outer margin of the belt should be confined to rocks of the Hilda Subgroup. The recognition of highly saline, chemically complex nonorogenic quartz vein-hosted fluid inclusions is considered critical from the point of view of base metal sulphide exploration.
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Foglietta, Mauro. "Depositional and tectonic controls on reservoir quality on the Apulian Platform margin, southern Apennines, Italy." Thesis, University of Reading, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.428163.
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Burgess, Samantha Nicole. "Neritic biofacies on the southern margin : feraminiferal profiles across the Great Australian Bight and the Bonney Shelf /." Title page, contents and abstract only, 1998. http://web4.library.adelaide.edu.au/theses/09SB/09sbb9557.pdf.
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Contreras, Jorham [Verfasser], and Thilo [Akademischer Betreuer] Bechstädt. "Seismo-stratigraphy and numerical basin modeling of the southern Brazilian continental margin / Jorham Contreras ; Betreuer: Thilo Bechstädt." Heidelberg : Universitätsbibliothek Heidelberg, 2011. http://d-nb.info/1179229681/34.
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Zhang, Peizhen. "Rate, amount, and style of late cenozoic deformation of southern Ningxia, northeastern margin of Tibetan Plateau, China." Thesis, Massachusetts Institute of Technology, 1988. http://hdl.handle.net/1721.1/60418.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Earth, Atmospheric, and Planetary Sciences, 1988.Five folded maps in pocket.
Includes bibliographies.
by Peizhen Zhang.
Ph.D.
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Chen, Yi. "The redefined centre, periphery and margin : the long-term interaction sphere of southern China 3000-221 BC." Thesis, University of Oxford, 2015. http://ora.ox.ac.uk/objects/uuid:0ae8b337-7a65-427d-9a37-9be7f4d17f9c.
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This thesis investigates southern China as a part of dynamic and extensive interregional networks from the third to the first millennium BC and explores the changing roles of different southern regions within the interregional relationships. This was an important transitional period for southern China as it was the time when several prominent and farreaching innovations of technologies and material culture were made or adopted in the area. Four key sets of materials – rice, bronze, ceramics and jade – are examined with a World-system perspective to reveal interregional contacts in different directions and of different nature between southern China and a number of neighbouring regions. By stressing on local responses towards different technologies and material culture in different period, an alternative narrative to that stemmed from Chinese historiography is, therefore, suggested. Instead of being a passive and 'backward' periphery in the traditional sense, southern China presents diversification of material culture over time. Many of the mechanisms of transmission and circulation in the south are characterised by 'leaked' technologies and designs, as well as 'selective adoption' and local redevelopment of material culture.
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Hague, Paul Frederick. "The structural and volcanic evolution of tertiary basins along the southern margin of the Rhodope Massif, northeastern Greece." Thesis, University of Southampton, 1993. https://eprints.soton.ac.uk/428198/.
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Prince, Philip S. "Evolution of transient topography on passive margins: A study of landscape disequilibrium in the southern Appalachian Mountains." Diss., Virginia Tech, 2011. http://hdl.handle.net/10919/77065.
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The mechanism through which the Appalachian Mountains have maintained moderate relief some ~300 Myr after the cessation of mountain building has long puzzled geomorphologists. As recent studies have shown that Appalachian exhumation has occurred at slow rates consistent with isostatic rebound of thickened crust, the driving forces behind localized episodes of accelerated incision and the associated rugged topography have been difficult to explain given the absence of tectonic uplift. This study uses previously undocumented relict fluvial gravels and knickpoint location to confirm the role of drainage rearrangement in producing local base level drop and subsequent basin-scale transient incision in the southern Appalachians. This process is fundamentally driven by the high potential energy of streams flowing across the elevated, slowly eroding Blue Ridge Plateau relative to the present Atlantic and landward interior base levels. Gravel deposits confirm that repeated capture of landward-draining Plateau streams by Atlantic basin streams, whose immediate base level is 250-300 m lower, forces episodic rapid incision and overall erosional retreat of the Blue Ridge Escarpment along the Plateau margin. The distribution of knickpoints, bedrock gorges, and relict surfaces in the interior of the Plateau indicate that the New River, which drains to the continental interior, is actively incising the low-relief Plateau surface due to episodic drops in landward base level. The origin of landward base level perturbation is unclear, but it may be the result of glacially-driven shortening and steepening of the lower New River during the Pleistocene. Collectively, these data indicate that rapid base level drop through drainage reorganization can energize streams in otherwise stable landscapes and accelerate fluvial incision and relief production without uplift of the land surface. This process is likely quite significant in post-orogenic settings, where inherited drainage patterns may not reflect the most direct, and thus energetically appropriate, path to present base level. Passive margins may therefore never achieve a topographic steady-state, despite uniformly slow and constant uplift due to isostatic rebound.Ph. D.
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Richardson, Janet Cristine. "Antecedent fluvial systems on an uplifted continental margin : constraining Cretaceous to present-day drainage basin development in southern South Africa." Thesis, University of Leeds, 2016. http://etheses.whiterose.ac.uk/14429/.
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Reconstructing drainage evolution has important implications for constraining long-term source-to-sink configurations. Furthermore, the analysis of ancient landscapes can support research in geomorphological concepts such as steady state and landscape evolution modelling. Techniques such as cosmogenic dating and morphometric analysis have rarely been applied to investigate the long-term drainage evolution of systems draining southern South Africa. This study focusses on the large-scale antecedent Gouritz catchment, Western Cape. Integrating provenance, cosmogenic and geomorphological (planform / morphometric indices) evidence indicates the trunk rivers are Cretaceous or older in age (i.e. principal topography of Mesozoic age). The trunk rivers fed huge volumes of sediment offshore during large-scale Mesozoic exhumation of southern South Africa with remnant coeval deposits in onshore extensional basins. However, there is a mismatch of onshore exhumation and offshore deposition and material is now found on the Falkland Plateau; separating source-to-sink by 6000 km. During exhumation, large scale pediments formed that grade to individual base levels and should be taken as individual features, not ‘surfaces’ correlated across the continent. A second phase of pediment evolution occurred in the mid-Cenozoic, dissecting the pediments and eroding small catchments into the Cape Fold Belt. These smaller order streams are strongly affected by the tectonic grain of the fold belt, whereas the trunk rivers are not, which is shown by variation in morphometric indices. The lack of correlation between catchment properties and denudation rates indicate the system has decoupled and that allogenic factors are now dominant. Due to the low rates of denundation, weathering is currently the rate limiting factor. However, during the early evolution of the catchment, tectonic activity was more dominant than the present day. The ancient catchment is in geomorphic steady-state, and highlights the need for further research into long-term landscape evolution, and linkage to offshore depositional records.
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Aygül, Mesut [Verfasser], Aral Akademischer Betreuer] Okay, and Roland [Akademischer Betreuer] [Oberhänsli. "Pre-collisional accretion and exhumation along the southern Laurasian active margin, Central Pontides, Turkey / Mesut Aygül ; Aral Okay, Roland Oberhänsli." Potsdam : Universität Potsdam, 2015. http://d-nb.info/1219149632/34.
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Aygül, Mesut [Verfasser], Aral [Akademischer Betreuer] Okay, and Roland [Akademischer Betreuer] Oberhänsli. "Pre-collisional accretion and exhumation along the southern Laurasian active margin, Central Pontides, Turkey / Mesut Aygül ; Aral Okay, Roland Oberhänsli." Potsdam : Universität Potsdam, 2015. http://d-nb.info/1219149632/34.
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Sattar, Nauman. "Mapping of Lower Cretaceous (Knurr Sandstone) turbidite lobes using Seismic Stratigraphy and prospectivity along the southern Loppa High Margin, Hammerfest Basin, Barents Sea, Norway." Thesis, Uppsala universitet, Geofysik, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-183699.
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The Hammerfest Basin was formed through downfaulting in Late Jurassic-Early Cretaceous times, allowing the deposition and preservation of Jurassic sediments which later were covered by thick Cretaceous sequences filling in the basin. This study has been conducted along the southern margin of the Loppa High to develop a complete sequence stratigraphic framework and to map Early Cretaceous Knurr Formation turbidite lobes along the slope of the High. Six seismic profiles have been selected for interpretation along the southern margin of the Loppa High on the basis of the availability of good quality data. A complete sequence stratigraphic framework has been developed to mark the major surfaces (Sequence Boundary, MFS) by geologic characterization of high-resolution seismic reflection geometries (truncation patterns, sigmoidal reflections) and seismic facies using the coarsening-up, fining up and blocky GR log motifs from both the offset wells and the wells located on the seismic section. Two Wheeler Diagrams (Chronostratigraphic Charts) have been constructed for type sections to obtain better insight into the time relationships of the depositional system, and define surfaces of non-deposition, condensation and erosion. WinPICS interpretation software has been used for seismic interpretation. Sequence stratigraphic analysis has been carried out on two scales (3rd order and 2nd order cycles). The whole sedimentary package is divided into various sequences and system tracts. In addition to a detailed sequence stratigraphic analysis to investigate the hydrocarbon prospectivity, an Early Cretaceous turbidite sand lobe has been mapped (LHSG-84-428) using seismic stratigraphy and compared with a drilled analogue (well 7122/2-1). Two paleogeograhic maps have also been constructed to show the Early to Late Cretaceous progradation and accommodation space filling in the Hammerfest Basin.
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Sasseville, Christian. "Characteristics of Mesoarchean and Neoarchean suprascrustal sequences at the southern margin of North Caribou terrane in the Wallace Lake greenstone belt, Superior Province, Canada." Thesis, McGill University, 2002. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=29472.
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The Wallace Lake greenstone belt is located on the southern margin of the Uchi-Sachigo-Goudalie superterrane within the volcanic-rich Uchi subprovince of the Superior Province in southeastern Manitoba, Canada. Its stratigraphy consists of a Mesoarchean complex constituted of alluvial conglomerate derived from ca. 3000 Ma tonalite, overlain by a crustal contaminated mafic-ultramafic volcanic sequence. Both units were deformed and then intruded by a 2.92 Ga tonalite body and related dyke swarm. Thrust sheets of a tholeftic volcanic sequence of unknown age, of oceanic plateau affinity tectonically overlie this Mesoarchean complex. The tectonic assembly was associated with regional SW directed compression, resulting in NW-trending folding and faulting. No metamorphic break is observed within this tectonic package despite major faulting related to this event. Neoarchean (<2709 Ma) greywacke and polymictic conglomerate unconformably overlie these units, and were deformed by dextral transcurrent deformation. Finally, fault bounded low-strain alluvial greywackes mark the last recorded stratigraphic and structural event affecting this area.
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Perfili, Christopher M. "Lithofacies, Sequence Stratigraphy, and Sedimentology of Desert Creek Platform, Slope, and Basin Carbonates, Southern Margin of the Aneth Complex, Middle Pennsylvanian, Paradox Basin, Utah." BYU ScholarsArchive, 2020. https://scholarsarchive.byu.edu/etd/8741.
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The Aneth Field in the Paradox Basin (SE Utah) has produced nearly 500 MMbbls of oil from phylloid-algal and oolitic carbonate reservoirs of the lower and upper Desert Creek (Paradox Formation, Middle Pennsylvanian) sequences, respectively. The oil resides in a 150 to 200 foot-thick isolated carbonate platform located in a distal ramp setting on the southwest margin of the Paradox Basin. The horseshoe-shaped platform is roughly 12 miles in diameter with an aerial extent of approximately 144 square miles. Evaluation of the platform-to-basin transition on the leeward (southern) margin of the Aneth Platform, the focus of this study, was made possible through Resolute Energy's 2017 donation of well data and core to the Utah Geological Survey Core Research Center. The lower Desert Creek sequence ranges from 50 to 100 feet in thickness and produces from a succession of phylloid-algal, boundstone-capped parasequences in the Aneth Platform. The upper Desert Creek sequence is generally thinner across the platform and is characterized by a succession of oolite-capped parasequences, except on the southern margin of the platform where it ranges from 80 to 115 feet in thickness. The upper Desert Creek “thick†resulted from southward shedding of platform-derived carbonate sediment and lesser amounts of quartz silt and very fine sand off the low-angle southern platform margin slope. A nine-mile-long, north-south-oriented stratigraphic panel constructed from log and core data permits characterization of thickness and facies trends through the upper Desert Creek from platform (north) to slope to distal basin (south) in the Ratherford unit. In the southern margin, five novel facies for the Aneth Field were analyzed, described, and interpreted using a sequence stratigraphic framework, all of which represent deposition on a gravity-influenced platform-edge slope. It is interpreted that the slope facies association was deposited during transgression and highstand and was generally a result of oversteepened slopes as a function of the carbonate factory on the platform being highly productive. Slope and basin facies range from proximal rudstone and floatstone to thin, graded distal turbidites, the latter of which extend at least five miles into the basin. Compaction of the muddy and fine-grained allochthonous sediment followed by pervasive calcite and anhydrite cementation has destroyed any primary porosity in the platform-derived slope-to-basin sediments.
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Gharbi, Mohamed. "Relationship between the southern Atlas foreland and the eastern margin of Tunisia (Chotts-Gulf of Gabes) : tectono-sedimentary, fault kinematics and balanced cross section approaches." Thesis, Aix-Marseille, 2013. http://www.theses.fr/2013AIXM4340/document.
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L'architecture structurale de l’avant-pays sud atlasique tunisien est caractérisée par un style tectonique mixte résultant de la réactivation de failles normales connectées avec le socle, de la mise en place de décollements dans la couverture sédimentaire ainsi que d’un diapirisme non négligeable. La géométrie et l’orientation des structures extensives préexistantes, issues du rifting Trias à Turonien, contrôlent la déformation de la couverture sédimentaire au cours des phases compressives d’âge fini-mésozoïque et cénozoïque. En effet, la marge tunisienne a enregistrée une longue période de rifting, de la fin du Permien-Trias jusqu’au Turonien. Une inversion tectonique s’est initiée probablement pendant le Crétacé supérieur. Les compressions tectoniques tertiaires se sont produites au cours de trois périodes: l’Eocène, le Mio-Pliocène et le Plio-Quaternaire. Notre étude montre une variation temporel du champ de contrainte régional, d’un régime tectonique compressif de direction NW-SE d’âge Mio-Pliocène à un régime tectonique compressif de direction N-S à NNE-SSW d’âge Quaternaire à l’actuel. Ce changement de régime tectonique a lieu, soit à la fin du Pliocène, soit au début du Quaternaire. Et une variation spatiale du champ de contrainte, de la compression (Domaine atlasique de la Tunisie) à la transtension (Golfe de Gabès), semble se faire progressivement du Nord vers le Sud-Est. Cette étude souligne le rôle prépondérant des failles profondes héritées et acquises au cours de l'évolution de la marge passive sud téthysienne. Dans ce domaine, la restauration de notre coupe équilibrée montre un raccourcissement modéré en surface de l’ordre de 8.1 km (~7,3%)The structural architecture of the Tunisian foreland consists in a mixed tectonic style with deep-seated basement faults, shallower décollements within sedimentary cover and salt diapirism. Structural geometry and orientation of the pre-existing Triassic-Turonian extensional structures controlled subsequent contractional deformation within the sedimentary cover. The rifting of the margin started in the late Permian–Triassic and continued up to the Turonian. From the inversion of the successive compressions, the development of ENE-trending thrust-related anticlines such as the Orbata and Chemsi structures are controlled by the reactivation of the inherited Mesozoic faults. Geologic data from this region indicate that the positive tectonic inversion occurred probably during Late Cretaceous period. The Cenozoic tectonic compressions in the southern Atlassic domain occurred during three periods: Late Eocene, Late Miocene and Plio-Quaternary. The Fault kinematic analysis reveals a temporal change in states of stress that occurred during the Late Cenozoic. A paleostress (Miocene-Pliocene) state is characterized by a regional compressional tectonic regime with a mean N134±09°E trending compressional axis (σ1). A modern (Quaternary to present-day) state of stress also corresponds to compressional tectonic regime with a regionally mean N05±10°E trending horizontal σ1. This study underlines the predominant role of inherited basement structures acquired during the evolution of the southern Tethyan margin, and their influence on the geometry of the Atlassic fold-and-thrust belt. At the southern Atlas of Tunisia our restoration shows a surface shortening of ~8.1 km (~7.3%)
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Schöner, Robert. "Comparison of Rotliegend sandstone diagenesis from the northern and southern margin of the North German Basin, and implications for the importance of organic maturation and migration." [S.l.] : [s.n.], 2006. http://deposit.ddb.de/cgi-bin/dokserv?idn=982751273.
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Ugueto, Lilian L. Navarro. "Depositional architecture and evolution of deep-water base-of-slope and slope channel complexes in a passive-margin setting: Isaac Formation, Windermere Supergroup (Neoproterozoic), southern Canadian Cordillera." Thesis, University of Ottawa (Canada), 2006. http://hdl.handle.net/10393/27278.
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The Isaac Formation in the Neoproterozoic Windermere Supergroup crops out in the Castle Creek South area (southwestern Canadian Cordillera) and consists of a more than 1.2 km-thick, laterally continuous slope deposit formed along the ancestral passive margin of western North America. Within the study area, six channel complex sets have been recognized, of which two, named informally Channels 1 and 3, are the focus of this study. Channel 1 exposes an oblique section of base-of-slope channel deposits, whereas Channel 3, at least in its lower part, is a flow-transverse section.
Channels 1 and 3 are 200-300 m thick and laterally extend over 1.1 km, and were initiated following two major falls of relative sea level. Detailed relationships between the intrachannel facies, architecture and geometry within both complex sets indicates that each comprises several vertically-stacked channel complexes that locally are separated by thin-bedded, mudstone-dominated turbidites interpreted to represent channel-abandonment deposits.
Each channel complex consists of several channel units, which, in turn, are composed of multiple channel fills. Channel fills are up to 30 m thick and show different infill geometries (amalgamated, semi-amalgamated or layered, non-amalgamated and accretionary), exhibiting systematic lateral changes in fill from channel axis to channel margin.
Multistory and multilateral fills in Channels 1 and 3 record a complex repetitive history of channel incision/bypass, aggradation, deactivation, migration and reincision. These erosional and depositional episodes are the result of changes in the equilibrium channel profile, flow parameters, and/or eustatic fluctuations.
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He, Yanhong, and 何艷紅. "Ages and geochemistry of the Xiong'er volcanic rocks along the southern margin of the North China Craton: implications for the outgrowths of the paleo-mesoproterozoicsupercontinent Columbia (Nuna)." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2008. http://hub.hku.hk/bib/B4163424X.
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Huber, Barbara [Verfasser], and Heinrich [Akademischer Betreuer] Bahlburg. "Provenance analysis of sediments from IODP Expedition 341 sites U1417 and U1418 : implications on climate-tectonic interactions at the southern Alaska continental margin / Barbara Huber ; Betreuer: Heinrich Bahlburg." Münster : Universitäts- und Landesbibliothek Münster, 2019. http://d-nb.info/1188706454/34.
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He, Yanhong. "Ages and geochemistry of the Xiong'er volcanic rocks along the southern margin of the North China Craton implications for the outgrowths of the paleo-mesoproterozoic supercontinent Columbia (Nuna) /." Click to view the E-thesis via HKUTO, 2008. http://sunzi.lib.hku.hk/hkuto/record/B4163424X.
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Andrade, Poliana Carvalho de. "Variações de paleoprodutividade na plataforma continental interna ao largo de Itajaí-SC (26º59'16.8\"S - 048º04'33.6\"W) durante o Holoceno: uma abordagem de multi-indicadores." Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/21/21133/tde-27072011-110113/.
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Análises microfaunísticas, sedimentológicas e geoquímicas realizadas em testemunho coletado na plataforma interna ao largo de Itajaí, SC, (26°5916,8S -048°0433,6W) permitiram reconhecer nos últimos 7.600 anos, três fases com distintas condições de fluxos de matéria orgânica e hidrodinâmicas. A primeira fase (7.600 5.000 anos cal. A.P.) é caracterizada por baixa produtividade, constatada pelos baixos valores dos indicadores de produtividade (Corg, CaCO3 e índice Benthic Foraminífera High Productivity - BFHP), condições hidrodinâmicas mais intensas (predomínio de areia e alta frequência de Globocassidulina subglobosa) e águas mais oxigenadas (valores elevados do índice Benthic Foraminífera Oxic Index BFOI e porcentagens relativamente altas de espécies epifaunais). O clima nesse período era relativamente mais seco e o nível médio do mar estava aproximadamente 3 m acima do atual. A segunda fase (5.000 3.000 anos cal. A.P.) é marcada pelo relativo incremento na paleoprodutividade (aumento de Corg, CaCO3 e índice BFHP), condições hidrodinâmicas menos intensas (baixa frequência de G. subglobosa e aumento no conteúdo de lama) e diminuição na disponibilidade de oxigênio nas águas de fundo (valores relativamente baixos do índice BFOI). O clima aparentemente torna-se progressivamente mais úmido e há diminuição progressiva do nível relativo do mar. A terceira fase (3.000 900 anos cal. A.P.) é caracterizada por aumento expressivo na produtividade (maiores porcentagens de Corg, CaCO3 e do índice BFHP e altas frequências de espécies infaunais e detritívoras), provavelmente as correntes de fundo são menos intensas (predomínio de sedimentos lamosos e baixa frequência de G. subglobosa) e com conteúdo de oxigênio mais restritivo (valores relativamente baixos do índice BFOI). Nesse período, há aumento significativo no aporte de material terrígeno, evidenciado por acentuado incremento na frequência de Buliminella elegantissima e das razões Fe/Ca e Ti/Ca. O aumento na produtividade poderia estar relacionado ao aumento da umidade ao longo do Holoceno, devido à intensificação do Sistema de Monções da América do Sul (SMAS) ocasionada por variações no ciclo de precessão e possivelmente aumento na frequência de El Niño, que corroboram para o aumento de chuvas no sul do Brasil. O clima mais úmido e o fortalecimento de frentes frias (ventos de S/SW) poderiam ter favorecido à penetração de águas frias e ricas em nutrientes vindas do sul, relacionada à descarga do Rio da PrataMicrofaunal, sedimentological and geochemical analyses from a core collected on the inner shelf off Itajaí, SC, allowed us to recognized , in the last 7,600 years, three phases with different organic matter fluxes and hydrodynamic conditions. The rst phase (7,600 5,000 years cal. B.P.) is characterized by low productivity, evidenced by low values of productivity proxies (organic carbon (Corg), calcium carbonate (CaCO3) and Benthic Foraminífera High Productivity index - BFHP), more intense hydrodynamic regime (dominance of coarser sediments and higher frequencies of Globocassidulina subglobosa) and waters with more oxygen availability (higher values of the Benthic Foraminífera Oxic Index BFOI and relatively high percentages of epifaunal species). The climate during this period was relatively dry and sea-level was approximately 3 m above the present. The second phase (5,000 3,000 years cal. B.P.) is marked by a relative increase in productivity (increase of Corg, CaCO3 and BFHP), hydrodynamical conditions were probably less intense (lower frequencies of G. subglobosa and muddy sediments), and oxygen availability decreased (lower BFOI index values). The climate apparently became progressively more humid and a progressive decline of the sea-level occurred. The third phase (3,000 900 years cal. B.P.) is characterized by a significant increase of productivity (higher percentages of Corg, CaCO3, infaunal and detritivores species, and increase of BFHP index values), probably bottom currents were less intense (muddy sediments and lower frequencies of G. subglobosa) and oxygen contents more restrictive (lower BFOI values). A significant increase in the input of continental material occurs during this period, as highlighted by an increase of Buliminella elegantissima frequencies and increase of the Fe/Ca and Ti/Ca ratios. The increase of productivity could be related to moisture increase throughout the Holocene, due to the intensification of the South American Monsoon system (SAMS) caused by variations in the precession cycle and possibly increased El Niño frequency, which corroborates the increase in rainfall in southern Brazil. The wetter climate and strengthening cold front may have favored the penetration of cold water rich in nutrients from the south, related to the discharge of the Rio de La Plata
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Wobbe, Florian [Verfasser], Vikram [Akademischer Betreuer] Unnithan, Karsten [Akademischer Betreuer] Gohl, Klaus [Akademischer Betreuer] Grosfeld, Carmen [Akademischer Betreuer] Gaina, and Primio Rolando [Akademischer Betreuer] Di. "Crustal and lithosphere dynamics of the Southern Pacific and the West Antarctic margin / Florian Wobbe. Betreuer: Vikram Unnithan ; Karsten Gohl. Gutachter: Vikram Unnithan ; Klaus Grosfeld ; Carmen Gaina ; Rolando Di Primio." Bremen : IRC-Library, Information Resource Center der Jacobs University Bremen, 2014. http://d-nb.info/1087315581/34.
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Sonibare, Wasiu Adedayo. "Structure and evolution of basin and petroleum systems within a transformrelated passive margin setting : data-based insights from crust-scale 3D modelling of the Western Bredasdorp Basin, offshore South Africa." Thesis, Stellenbosch : Stellenbosch University, 2015. http://hdl.handle.net/10019.1/96832.
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Thesis (PhD)--Stellenbosch University, 2015.ENGLISH ABSTRACT: This study investigates the crustal structure, and assesses the qualitative and quantitative impacts of crust-mantle dynamics on subsidence pattern, past and present-day thermal field and petroleum system evolution at the southern South African continental margin through the application of a multi-disciplinary and multi-scale geo-modelling procedure involving both conceptual and numerical approaches. The modelling procedure becomes particularly important as this margin documents a complex interaction of extension and strike-slip tectonics during its Mesozoic continental rifting processes. Located on the southern shelf of South Africa, the Western Bredasdorp Basin (WBB) constitutes the focus of this study and represents the western section of the larger Bredasdorp sub-basin, which is the westernmost of the southern offshore sub-basins. To understand the margin with respect to its present-day structure, isostatic state and thermal field, a combined approach of isostatic, 3D gravity and 3D thermal modelling was performed by integrating potential field, seismic and well data. Complimenting the resulting configuration and thermal field of the latter by measured present-day temperature, vitrinite reflectance and source potential data, basin-scale burial and thermal history and timing of source rock maturation, petroleum generation, expulsion, migration and accumulation were forwardly simulated using a 3D basin modelling technique. This hierarchical modelling workflow enables geologic assumptions and their associated uncertainties to be well constrained and better quantified, particularly in three dimensions. At present-day, the deep crust of the WBB is characterised by a tripartite density structure (i.e. prerift metasediments underlain by upper and lower crustal domains) depicting a strong thinning that is restricted to a narrow E-W striking zone. The configuration of the radiogenic crystalline crust as well as the conductivity contrasts between the deep crust and the shallow sedimentary cover significantly control the present-day thermal field of the study area. In all respects, this present-day configuration reflects typical characteristics of basin evolution in a strike-slip setting. For instance, the orientations of the deep crust and fault-controlled basin-fill are spatially inconsistent, thereby indicating different extension kinematics typical of transtensional pull-apart mechanisms. As such, syn-rift subsidence is quite rapid and short-lived, and isostatic equilibrium is not achieved, particularly at the Moho level. Accompanied syn-rift rapid subsidence and a heat flow peak led to petroleum preservation in the basin since the Early Cretaceous. Two additional post-rift thermal anomalies related to the Late Cretaceous hotspot mechanism and Miocene margin uplift in Southern Africa succeeded the syn-rift control on maturation. This thermal maturity of the five mature source rocks culminated in four main generation and three main accumulation phases which characterise the total petroleum systems of the WBB. The Campanian, Eocene and Miocene uplift scenarios episodically halted source maturation and caused tertiary migration of previously trapped petroleum. Petroleum loss related to the spill point of each trap configuration additionally occurs during the Late Cretaceous-Paleocene and Oligocene-Early Miocene. The timing and extent of migration dynamics are most sensitive to the geological scenario that combined faulting, intrusive seal bypass system and facies heterogeneity. In fact, for models that do not incorporate facies heterogeneity, predicted past and present-day seafloor leakage of petroleum is largely underestimated. This complex interplay of generation and migration mechanisms has significant implications for charging of petroleum accumulations by multiple source rocks. Due to early maturation and late stage tertiary migration, the syn-rift source rocks particularly Mid Hauterivian and Late Hauterivian source intervals significantly control the extent of petroleum accumulation and loss in the basin. Lastly, the modelled 3D crustal configuration and Mezosoic to Cenozoic thermal regime of the WBB dispute classic uniform lithospheric stretching for the southern South African continental margin. Rather, this PhD thesis confirms that differential thinning of the lithosphere related to a transtensional pull-apart mechanism is the most appropriate for accurately predicting the evolution of basin and petroleum systems of the margin. Also, the presented 3D models currently represent the most advanced insights, and thus have clear implications for assessing associated risks in basin and prospect evaluation of the margin as well as other similar continental margins around the world.
AFRIKAANSE OPSOMMING: Hierdie studie ondersoek die korsstruktuur en evalueer die kwalitatiewe en kwantitatiewe impakte van kors-mantel-dinamika op insinkingspatroon, die termiese veld en petroleumstels evolusie aan die suidelike Suid-Afrikaanse kontinentale grens, in die hede en die verlede, deur die toepassing van ’n multidissiplinêre en multiskaal-geomodelleringsprosedure wat beide konseptuele en numeriese benaderings behels. Die modelleringsprosedure veral is belangrik aangesien hierdie kontinentale grens ’n komplekse interaksie van uitbreidings- en strekkingsparallelle tektoniek gedurende die Mesosoïese vastelandskeurprosesse daarvan dokumenteer. Omdat dit op die suidelike platvorm van Suid-Afrika geleë is, maak die Westelike Bredasdorp Kom (WBK) die fokus van hierdie studie uit, en verteenwoordig dit die westelike deel van die groter Bredasdrop-subkom, wat die verste wes is van die suidelike aflandige subkomme. Om die grens met betrekking tot sy huidige struktuur, isostatiese staat en termiese veld te verstaan, is ’n kombinasie benadering bestaande uit isostatiese, 3D-gravitasie- en 3D- termiese modellering gebruik deur potensiëleveld-, seismiese en boorgatdata te integreer Ondersteunend totot die gevolglike konfigurasie en termiese veld van die laasgenoemde deur middel van hedendaagse temperatuur, soos gemeet, vitriniet-refleksiekoëffisiënt en bronpotensiaal data, komskaal-begrawing en termiese geskiedenis en tydsberekening van brongesteentematurasie, is petroleumgenerasie, -uitwerping, -migrasie en -akkumulasie in die toekoms gesimuleer deur gebruik te maak van ’n 3D-kommodelleringstegniek. Hierdie hierargiese modelleringswerkvloei maak dit moontlik om geologiese aannames en hulle geassosieerde onsekerhede goed aan bande te lê en beter te kwantifiseer, veral in drie dimensies. In die hede word die diep kors van die WBK gekarakteriseer deur ’n drieledige digtheidstruktuur (met ander woorde voorrift-metasedimente onderlê deur bo- en benedekors domeine) wat dui op ’n baie wesenlike verdunning, beperk tot ’n dun O-W-strekkingsone. Die konfigurasie van die radiogeniese kristallyne kors, sowel as die konduktiwiteitskontraste tussen die diep kors en die vlak sedimentêre dekking, beheer grotendeels die hedendaagse termiese veld van die studiearea. Hierdie hedendaagse konfigurasie weerspieël in alle opsigte tipiese eienskappe van kom-evolusie in ’n skuifskeur omgewing. Byvoorbeeld, Die oriëntasies van die diep kors en verskuiwingbeheerde komsedimentasie byvoorbeeld is ruimtelik inkonsekwent en dui daardeur op verskillende ekstensiekinematika, tipies van transtensionale tensiemeganisme. As sulks, is sin-rift-versakking taamlik vinnig en kortstondig, en word isostatiese ekwilibrium nie by die Moho-vlak, in die besonder, bereik nie. Samehangende sin-rift vinnige versakking en hittevloeihoogtepunt het gelei tot petroleum behoud in die kom sedert die vroeë Kryt. Twee bykomende post-rift termiese anomalieë wat verband hou met die laat Kryt-“hotspot” meganisme en die Mioseense kontinentale grensopheffing in Suidelike Afrika het die sin-rift-beheer met maturasie opgevolg. Hierdie termiese maturiteit van die vyf gematureerde brongesteentes het in vier hoofgenerasie- en drie hoofakkumulasie fases, wat die totaliteit van die petroleumstelsels van die WBK karakteriseer, gekulmineer. Die Campaniese, Eoseense en Mioseense opheffings senarios het episodies bronmaturasie gestop en tersiêre migrasie van petroleum wat vroeër opgevang was veroorsaak. Addisioneel vind petroleumverlies gekoppel aan die spilpunt van elke opvanggebiedkonfigurasie tydens die laat Kryt-Paleoseen en Oligoseenvroeë Mioseen plaas. Die tydstelling en omvang van migrasiedinamika is die sensitiefste vir die geologiese scenario wat verskuiwing, seëlomseilingstelsel en fasiesheterogeniteit kombineer. Trouens, vir modelle wat nie fasiesheterogeniteit inkorporeer nie, is voorspellings van vroeëre en huidige seebodemlekkasie van petroleum grotendeels onderskattings. Hierdie komplekse wisselwerking van generasie- en migrasiemeganismes het beduidende implikasies vir die laai van petroleumakkumulasies deur veelvoudige brongesteentes. Vanweë vroeë maturasie en laatstadiumtersiêre migrasie, oefen die sin-rift-brongesteentes, veral middel Hauterivium- en laat Hauteriviumbronintervalle, beduidende beheer oor die omvang van petroleumakkumulasie en -verlies in die kom uit. Laastens weerspreek die gemodelleerde 3D-korskonfigurasie en Mesosoïese-tot-Senosoïesetermiese regime van die WBK ’n klassieke uniforme litosferiese rekking vir die suidelike Suid- Afrikaanse kontinentale grens. Inteendeel, hierdie PhD-proefskrif bevestig dat ’n differensiële verdunning van die litosfeer, gekoppel aan ’n transtensiemeganisme, die beste geskik is om ’n akkurate voorspelling oor die evolusie van kom- en petroleumstelsels van die kontinentale grens mee te maak. Verder, verteenwoordig die 3D-modelle, wat hier aangebied word, tans die mees gevorderde insigte, en het hierdie modelle dus duidelike implikasies vir die assessering van verwante risiko’s in kom- en petroleum teikene valuering van die kontinentale grens, so wel as van ander soortgelyke kontinentale grense regoor die wêreld.
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Altman, Pamela Frost. "Marvin S. Pittman : a historical inquiry of his life, legacy and leadership /." Click here to access dissertation, 2007. http://www.georgiasouthern.edu/etd/archive/spring2007/paltman/Altman_Pamela_F_2000701_edd.pdf.
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Thesis (Ed.D.)--Georgia Southern University, 2007."A dissertation submitted to the Graduate Faculty of Georgia Southern University in partial fulfillment of the requirements for the degree Doctor of Education." Under the direction of Meta Y. Harris. ETD. Electronic version approved: May 2007. Includes bibliographical references (p. 143-150) and appendices.
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Omre, Anette. "An economic transport system of the next generation integrating the northern and southern passages." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for marin teknikk, 2012. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-18541.
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The ice cap surrounding the Arctic Ocean has been significantly reduced during the last decades. As the ice continues to diminish the economic potential of the NSR is becoming stronger. However there are still challenges and uncertainties connected to navigation in the Arctic. Among these are the lack of marine infrastructure, the uncertainties regarding the regulations and length of the ice free season. The purpose of this master thesis is therefore to develop a transport simulation model to investigate the economic feasibility of a NSR transport system. The route has not been evaluated as a year-round substitute for the traditional route through the Suez Canal, but has been integrated with the southern passage. As a result the Northern Sea Route is only used as an alternative in the navigation season between August and the end of November. In order to investigate the feasibility of the route a case study is developed. Container cargo is evaluated as the most suitable shipping cargo; therefore the case study presents a possible container transport between Rotterdam in the Netherlands and Yokohama in Japan. The shorter distance of the NSR is exploited in two ways, either by slow steaming or increasing the number of transits a year. In addition the transport systems are evaluated for 4 different ice classes, 7 different ice scenarios and a fleet consisting of 6 or 7 vessels. The transport simulation model calculates the speed and fuel consumption in ice with the use of an ice thickness-speed curve (h-v curve). The h-v curve is found by calculating the ice resistance of the vessel for variable ice thicknesses and the corresponding net thrust available to overcome this resistance. Further the model simulates the schedules and calculates the total fuel consumption for the entire fleet. The output of the model is the required freight rate (RFR) for the NSR transport systems and the Suez Canal route.The simulation results indicate that:-The optimal fleet size consist of 7 vessels-The slow steaming schedule is more profitable than the maximum transits schedule-The optimal ice class for the less severe ice scenarios are IC, while IB is better when the ice conditions harshen-All ice classes are more profitable than the SCR if the ice conditions are less severe than ice scenario 5
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Duncan, Faith Louise, and Faith Louise Duncan. "Botanical reflections of the encuentro and the Contact Period in southern Marin County, California." Diss., The University of Arizona, 1992. http://hdl.handle.net/10150/185977.
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Plant indicator species and longitudinal paleobotanical data were used as independent measures to document the human ecological record of the contact period in southern Marin County, California. These data suggest that archaeological and documentary records are insufficient for examining changes in land management and use during the contact period. Prior to A.D. 1579, Western Miwok peoples had not encountered Europeans face to face. This early phase of the contact period is marked the possible introduction of New World species through passive cultural vectors. Two brief encounters occurred between the Miwok and Europeans between A.D. 1579 and 1775. Introduced and weedy plant species from fossil samples appear to confirm these encuentros and confirm the archeological evidence for intermittent contact during the second phase of the contact period. Modern and fossil pollen samples suggest that the intensity of human disturbance is geographically stratified and related to exploration, procurement, and management of specific resources. Coastal prairie, the redwood forest, and Bay salt marshes were the most affected by the second phase of the contact period. Shifts in vegetation diversity and increases in the numbers of introduced and weedy species were compared between ruderal and undisturbed contexts. These data were used as analogs to monitor the final phase of contact between A.D. 1775 to 1817. Hypotheses derived from ethnohistoric and ethnographic sources that suggest rapid shifts in land management practices and changes in plant representation were corroborated by some pollen data. Specifically, the ecological responses to the suppression of anthropogenic burning, changes in land tenure and parcelization, and the initiation of grazing and logging practices were examined. The cumulative impacts of introduced plants, shifts in land management from Miwok to Euroamerican-dominated resource procurement and subsistence practices, and ecological responses of plant species suggests that the contact period might better be defined on ecological terms rather than by purely material cultural or ethnographic definitions. In southern Marin, paleobotanical data provide a measurable indication of the ecological character of the pre-contact landscape and the cultural processes that effectively altered its character during the contact period.
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Glinton, Jr Vaughn. "Southern Honor: An Analysis of Stand Your Ground Law in Southern Jurisdictions." Honors in the Major Thesis, University of Central Florida, 2013. http://digital.library.ucf.edu/cdm/ref/collection/ETH/id/1542.
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In 2005, Florida became the first state to pass the heavily National Rifle Association, NRA, supported “Stand Your Ground” law. The most notable components of the law were abolishing the duty to retreat for someone who is not engaged in lawful activity and is in a place where he has the right to be, granting civil and criminal immunity to those using lawful force, and presuming that a person who is attacked in his dwelling, residence, and occupied vehicle has a reasonable fear of death or great bodily harm. The law was subject to a substantial amount of criticism because it was a significant departure from Florida’s more than a century old common law principles regarding self-defense. Possibly due to Florida not having any precedents for these cases, Florida courts would have conflicting decisions in these matters and law enforcement agencies would enforce the law differently in similar incidents. Regardless of the issues faced by Florida, over twenty states would adopt their own versions. A significant number of these states are in the Southeastern region of the United States and are neighbors to Florida or border Florida’s neighbors, such as Mississippi, Alabama, Georgia, North Carolina, South Carolina, Tennessee, and Louisiana. Because of this interesting pattern, the study examines the idea of southern culture playing a role in the passage of “Stand Your Ground” via the “Culture of Honor” theory and the researcher decided to use these jurisdictions and Florida as this study’s sample. The researcher also wanted to include these jurisdictions because the existing “Stand Your Ground” literature mainly focuses on Florida and the researcher wanted to add something new to the discussion. The intent of this study to examine Florida’s influence on the other jurisdictions, note any commonalties between the statutes of the jurisdictions, compare justifiable homicide statistics for the jurisdictions that provided such data, predict the future of these laws, and explore the “Culture of Honor” Theory as a possible explanation for “Stand Your Ground” laws in the states discussed. The study accomplished these goals by examining how each jurisdiction handled self-defense before “Stand Your Ground,” looking at the motives behind the jurisdictions adopting “Stand Your Ground,” comparing justifiable homicides in the four jurisdictions that provided them in the years immediate preceding the passage of “Stand Your Ground” to the subsequent years, and looking at amendments and proposals that were presented after the passage of “Stand Your Ground.” The results uncovered that all the jurisdictions, except for Georgia and Tennessee, show a very strong Florida influence based on their similarities to Florida’s law and legislators in the jurisdictions clearly mentioning Florida as their inspiration for proposing their own versions. In the jurisdictions that provided justifiable homicides, all showed an increase in the number of justifiable homicides after the passage of “Stand Your Ground.” The jurisdictions in this study have also shown a strong resistance to any amendments or the complete repeal of this law. Therefore, any drastic amendment or the complete repeal seems unlikely in the future. The “Culture of Honor” Theory does explain why a few of the jurisdictions in the study adopted “Stand Your Ground” but Florida and the NRA’s influence explain why others chose this course of action.B.S.
Bachelors
Health and Public Affairs
Legal Studies
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Mulvanity, Laura Mathis. "Women in science stories from the margins /." Click here to access dissertation, 2008. http://www.georgiasouthern.edu/etd/archive/spring2008/laura_m_mulvanity/mulvanity_laura_m_200801_edd.pdf.
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Thesis (Ed.D.)--Georgia Southern University, 2008."A dissertation submitted to the Graduate Faculty of Georgia Southern University in partial fulfillment of the requirements for the degree Doctor of Education." Under the direction of John Weaver. ETD. Electronic version approved: May 2008. Includes bibliographical references (p. 139-149)
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Whiteman, Mark Ian. "The anatomy of Mesozoic carbonate platform-margins, southern Apennines, Italy." Thesis, University of Oxford, 1989. http://ora.ox.ac.uk/objects/uuid:f4df240b-cce7-4ac6-8c40-504e2187d018.
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The stratigraphy and sedimentology of Mesozoic carbonate platform-margins cropping out in southern Italy are investigated. New strati graphic data are presented from northern and eastern slopes of the Apennine carbonate platform, based on locallycorrelated field sections. Thin-section petrography is used to demonstrate the spatial and temporal distribution of derived lithoclasts. Results indicate that southern Apennine platforms underwent repeated erosion during Cretaceous time and possible reasons for this are discussed. Petrographic studies also provided outline sediment parageneses for slopes and platforms, with special reference to the detailed geochemistry of secondary dolomite formation on the eastern margin of the Apulian platform, whose growth is indicated by proton microprobe microanalysis to have been influenced by redox changes. The sedimentary facies and sediment geometries of Upper Cretaceous to Lower Tertiary slope sediments mapped in the Frosolone area are discussed in a case-study. Cross-sections showing geometries of key beds are presented, and depositional controls are discussed. Outcrop data suggest an Early to Middle Jurassic age of basin formation of this sector of the Lagonegro-Molise basin. A further case study from the Mesozoic slope in the Gran Sasso shows sediment geometries at reflection seismic scale, and relates them to possible depositional control by relative sea-level fluctuations. Finally, data from southern Apennine platforms and basins are combined in a tentative sequence stratigraphic framework for the Middle Cretaceous. The results of onedimensional subsidence modelling are presented in order to separate and describe the signals of local tectonics and relative sea-level fluctuations affecting the southern passive-margin of Mesozoic Tethys.
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Drass, Richard. "Culture change on the eastern margins of the Southern Plains /." Full-text version available from OU Domain via ProQuest Digital Dissertations, 1995.
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Nikolova-Houston, Tatiana Nikolaeva. "Margins and marginality : marginalia and colophons in south Slavic manuscripts during the Ottoman period, 1393-1878 /." Austin, Tex. : The University of Texas, 2008. http://www.lib.utexas.edu/etd/d/2008/nikolovahoustond21244/nikolovahoustond21244.pdf#page=3.
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Chaudhury, Suman. "Marine geophysical studies of the southern margins of the Iberian Peninsula." Thesis, University of Oxford, 1999. http://ora.ox.ac.uk/objects/uuid:1ee8721f-9324-48bd-8d57-b645e02d75fd.
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A wide variety of tectonic settings are juxtaposed at the southern margins of the Iberian Peninsula. The regional geology comprises an Atlantic passive margin in western Iberia, the convergent eastern part of the Azores-Gibraltar plate boundary zone between Africa and Eurasia, and an orogenic arc (the Betic-Rif mountains) surrounding an extensional basin (the Alboran Sea). The complex tectonic history of the southern Iberian margins is recorded in its sediments and structure, and these were investigated in this study using multichannel seismic reflection techniques in conjunction with other marine geophysical data. Multichannel seismic reflection and well data from the Gulf of Cadiz have shown that the earliest sediments are Triassic evaporites, followed by Jurassic carbonates, which form rotated fault blocks in the Gulf of Cadiz. Backstripping and thermal modelling has indicated that a rifting event took place in the Late Jurassic, which stretched the crust by ~20-50%. Gravity modelling, and mapping of stretching factors, has suggested that two zones of thinning underlie the Gulf of Cadiz, which are related to the original rifting event. Backstripped subsidence curves indicate passive margin thermal subsidence until the Miocene, when westward-directed thrusting and loading from the Betic-Rif mountain belt is reflected in a typical foreland basin tectonic subsidence signature of accelerated subsidence with time. A giant, chaotic body of allochthonous sediment was emplaced into the central Gulf of Cadiz as westward migration of the Gibraltar Arc led to oversteepening of the margin west of the Gibraltar Straits, while the Alboran Sea was simultaneously undergoing active extension. These allochthonous deposits are composed mainly of Triassic evaporites and Palaeogene shales. In the Gulf of Cadiz and Seine Abyssal Plains this body has the appearance of an accretionary wedge, but a 300 km long northern lobe of the body extends into the Horseshoe Abyssal Plain. This lobe is interpreted as being a cumulative mass wasting feature, formed by the gravity-driven downslope transport of large allochthonous masses as debris flows and slides and slumps, encouraged by a regional gradient and a pre-existing trough in the Horseshoe Abyssal Plain. The total volume of sediments involved was of the order of 72 000 km 3 , and the time of emplacement has been estimated as being Tortonian on the basis of seismic correlation with core data at DSDP site 135. This chaotic unit has formed a series of longitudinal diapiric ridges in the northern Gulf of Cadiz, which have been interpreted to act as a transport system for gas generated in the lower slope area to migrate to the upper slope where gas-related features are seen. Gas hydrates are present beneath the lower continental slope, as inferred from a bottom-simulating reflection on seismic reflection profiles.
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Muedi, Thomas Tshifhiwa. "Cretaceous dyke swarms and brittle deformation structures in the upper continental crust flanking the Atlantic and Indian margins of Southern Africa, and their relationship to Gondwana break-up." Thesis, Nelson Mandela Metropolitan University, 2013. http://hdl.handle.net/10948/d1020896.
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Permanent brittle deformation of rocks of the upper crust is often manifested in the growth of fractures, or sliding along fractures, which may subsequently be intruded by magma and other fluids. The brittle deformation structures described here include faults, joints and dykes. Brittle deformation structures along passive continental margins result from continental fragmentation and related uplift, as is seen around the southern African margins in response to Gondwana break-up. In many cases the fragmentation is accompanied by significant magmatic events, for example the Cretaceous mafic dyke swarms that form major components of the South Atlantic Large Igneous Province (LIP) and originated during the break-up of West Gondwana (Africa and South America). The magmatic events accompanying the break-up of Gondwana resulted in crustal extension and the formation of joint systems and dyke swarms that exhibit distinct geometric features that appear to display fractal patterns. This work analyses the relationship between the Henties Bay-Outjo Dyke Swarm (HOD) on the west coast of Namibia, and the Ponta Grossa Dyke Swarm (PG) on the coast of Brazil, both of which formed ca. ~130 Ma, to test for their co-linearity and fractal geometry before and during West Gondwana break-up. This was achieved by reconstructing Gondwana‘s plates that contained the PG and HOD swarms, using ArcGIS and Gplates software. The dyke analyses was complemented with a comparative study of joints of the Table Mountain Group quartzites (TMG, ca. 400 Ma) in the Western Cape Province and Golden Valley Sill (GVS, ca. 180 Ma) in the Eastern Cape Province, to compare their fractal patterns and possible relationship. Mapping of joints was carried out in the field with the use of a compass and GPS. The HOD trend is positioned largely NNE > NE, but a NW dyke trend is also common. The dominant joints in the TMG trend NNW > WSW and the GVS joints trend WNW > NNE and others. The GVS and HOD orientations appear strongly correlated, while TMG shows no simple orientation correlation with GVS and HOD. The lack of correlation is attributed to the TMG‘s formation in different host-rocks with variable anisotropy and/or the presence of different mechanical processes acting at a different time in geological history. All mapped dykes and joints were analysed to test for fractal geometry. The fractal dimension results of about 18605 HOD dykes from microscopic to mega scale (0.1 mm – 100 km) shows fractal patterns that range between Df = 1.1 to 1.9; and the fractal dimension of about 1716 joints in the TMG and about 1026 joints in the GVS at all scales range between ca. Df = 1.6 to 1.9. The similarity of the fractal patterns indicates that joints and dykes may have formed in response to similar tectonic stress events; and similar orientations may indicate that joints pre-dated the dyke intrusions. However, the data also indicate that dykes are not always related to pre-existing joints.
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Hussein, Kassim Nurudin. "Bank Spreads, Margins, Concentration and Credit Risks in the Southern Africa Development Community." Thesis, Bangor University, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.516460.
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Angelo, dos Santos Silva Ricardo Miguel. "The identification of the ocean-continent transition at sediment-rich rifted continental margins : Northern Angola and Southern Australia rifted margins." Thesis, University of Liverpool, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.540040.
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Bellehumeur-Genier, Olivier. "Permafrost Patch Size Near the Margins of Discontinuous Permafrost, Southern Yukon and Northern B.C." Thesis, Université d'Ottawa / University of Ottawa, 2016. http://hdl.handle.net/10393/34969.
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This research focused on measuring permafrost patch size and related variables between Fort St. John, BC and Whitehorse, YT. Methods used included electrical resistivity tomography, climate monitoring, active layer measurement, analysis of historical aerial photos, and on-site near-vertical aerial imaging. Where permafrost is present along the transect, mean annual air temperature (2010-2014) varied from -3.3 ºC to -0.9 ºC, mean annual ground surface temperature from 0.7 ºC to 2.4 ºC and mean annual ground temperature from -0.3 ºC to 0.2 ºC (at TTOP). Permafrost patches are in the order of 10 – 50 000 m2 in area and there is a strong positive log-log relationship between patch area and maximum permafrost thickness. A conceptual model of permafrost patch size evolution under a warming climate is proposed. It is concluded that permafrost patch size depends on site-specific characteristics, the time since permafrost began to degrade and the local climate conditions.
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Petersson, Hampus. "The City as Socio-Ontology : Community, Locality and Social Space within a Minor City in Southern Sweden." Thesis, Uppsala universitet, Sociologiska institutionen, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-295766.
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In sociology in general, community is often seen as an expression for something seriously threatened or even destroyed by modernity. In urban sociology, this question has traditionally manifested itself in a ‘search exhibition’ of communal bonds within the city landscape. This analytical approach tends to split up ‘community’ and ‘city’ into two different forms of social experience. By adopting a socio-ontological approach, this study argues that experiences of community cannot be ontologically separated from experiences of the city. The aim of this study is to examine how the interviewees, living in the same neighborhood within a minor city in southern Sweden, create a perception of the city as a whole in relation to their own positioning therein. From this aim, two research questions have been formulated as follows: How is Milltown socio-ontologically constituted as a social space of relations? And: How do the interviewees construct a purified community? In order to examine this, nine in-depth interviews were conducted with residents in a middle class neighborhood (Greenwood), located in a minor city in southern Sweden (Milltown). The material was analyzed using a socio-ontological approach combined with Pierre Bourdieu’s concepts of social space and habitus, and Richard Sennett’s concepts of purified community and collective personality. The results of this study show how the perceived social complexity of Milltown as a whole is purified into an authentic experience of community. Greenwood is being constituted as a private sphere, which is isolated from the rest of the city. Greenwood represents a simplification of the social environment within the city landscape, where personal feelings and values are projected. It is also shown how interaction between neighbors in Greenwood is almost completely absent, and how the interviewees compensate this absence by constructing a collective personality. This collective personality envisages how they are the same, rather than what they actually do in their relations to each other. The feelings of belonging stem from shared expectations that neighbors have on each other, rather than from interactions. Finally, the results show how this purified community identity is constructed against other neighborhoods in Milltown, which are seen to represent different ways-of-life. This study contributes to a more complex understanding of how feelings of belonging are constituted in relation to a specific locality, but also how this understanding enables a perception of the city as a whole. Accordingly, insights have been achieved on how recent attempts to ‘redefine’ the community concept in sociology can be used empirically, and to be further built upon theoretically. Further, urban sociology has traditionally been concerned with big cities. This study argues that the urban sociological tradition has exaggerated the differences between minor and larger cities. The argument is that minor cities should be approached as socially complex milieus as well, where people are aware of each other but do not know each other. Gesellschaft relations should therefore not be understood as something exclusive to the metropolis, but rather as a condition of life in modernity in general. Finally, this study also gives an insight about the mechanisms behind voluntary segregation. This is a matter that is often neglected in urban sociological research, which traditionally has worked in paradigm of poverty, thus focusing on stigmatized neighborhoods.
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Nickelson, Joshua Bradley. "Evaluating the success of oak afforestation on former agricultural lands in southern Illinois." OpenSIUC, 2014. https://opensiuc.lib.siu.edu/theses/1560.
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AN ABSTRACT OF THE THESIS OF Joshua B. Nickelson, for the Masters of Science degree in Forestry, at Southern Illinois University Carbondale TITLE: EVALUATING THE SUCCESS OF OAK AFFORESTATION ON FORMER AGRICULTURAL FIELDS IN SOUTHERN ILLINOIS Major Professor: Dr. Eric Holzmueller The establishment of oak (Quercus spp.) plantations has increased over the past two to three decades to reduce fragmentation and promote wildlife habitat throughout the Midwestern United States. However, influences such as competing vegetation, previous land cover, plantation size, and site preparation techniques may have varying outcomes on restorative successes. We established 219 plots (.02 ha) in 29 oak plantations located within Crab Orchard National Wildlife Refuge (Williamson County, Illinois) 15-18 years after mechanical planting. Sampling data for all trees over breast height included species, diameter, and lianas existence on the main bole of the tree. Additionally, free-to-grow status was recorded for all oak saplings and estimated cover of the exotic invasive shrub Elaeagnus umbellata and vine Lonicera japonica were documented. Results show significantly higher numbers of total oaks and free-to-grow oaks in plantings previously cropped in clover and soybeans when compared to the fallow sites host to brush species that received treatment (mowing and or herbicidal application). Significantly less oaks in the soybean and clover categories possessed a vine on the main bole of the tree when compared to the treated brush sites. Brush sites showed a significantly less number of total trees compared to clover and soybean covers and a higher percent of autumn olive cover (%) compared to soybeans. No significance was found in the percent of oaks with a vine, the percent of oaks overtopped, E. umbellata density or L. japonica cover (%) across the four previous vegetation categories. One treatment of pre-planting mowing and herbicidal application is not effective on fallow sites that are host to early successional species and money should not be invested on Quercus trees or mowing and herbicidal treatments in these scenarios. The results suggest that it is best to plant Quercus species immediately following clover or soybean harvest on abandoned agricultural lands before early successional species become established.
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Ingram, Caroline S. "Ostracod palaeoecology and biogeochemistry of marine and estuarine interglacial deposits in North West Europe." Thesis, Bangor University, 1999. https://research.bangor.ac.uk/portal/en/theses/ostracod-palaeoecology-and-biogeochemistry-of-marine-and-estuarine-interglacial-deposits-in-north-west-europe(4cd7fd25-815b-4e1d-aebb-cada60a3d9b4).html.
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Ostracods were obtained from two cores in the southern North Sea area: the Sand Hole and Swarte Bank Formations of Tappin (1991) in BGS borehole 81/52A, cored from the Inner Silver Pit, southern North Sea, and a core from Shoeburyness in Essex, borehole S 1. The faunal assemblages in 131-181/52A were dominated by Sarsicytheridea punctillata, Elo/sonella concinna and Acanthocvthereis clunelmnensis. The assemblages recovered reflect a transition from glacio-marine conditions in the Swarte Bank Formation up into a cold-temperate marine environment in the Sand Hole Formation with deteriorating temperatures indicated at the top of the interval studied. In BHSI a freshwater to brackish transition occurred in the core, the freshwater section being dominated by Darwinula slevensoni and llyocypris spp., and the brackish section by Cyprideis torosa and C ytheromor pha fiiscata. The palaeoecology of the ostracod assemblages recovered is compared to other palaeoecological data from the same sections in each core and to ostracod data from other Hoxnian/l lolsteinian sites in north western Europe. These data are also discussed in the light of evidence indicating that there was a barrier across the southern North Sea when the sediments examined were deposited. Sarsicytheridea spp. and (yprideis terosa were used for trace element (Mg: Ca, Sr: Ca) and stable isotope (cS'"O, ö'3C) analyses. A calibration equation for the calculation of temperature from Mg: Ca ratio was successfully established from analysis of modern Sarsicytheridea. Modern Sr: Ca data could not be used to establish a calibration for salinity since there was too much scatter in the data. (' prideis torosa has been used for trace element and stable isotope work by other authors who have published relationships between ('yprideis and the water chemistry. Ostracods were also analysed down core to examine the changing ratios of Mg and Sr as a proxy for temperature and salinity changes in the I-loxnian of the southern North Sea. In BH81/52A, Mg: Ca data indicated a deterioration in temperature from 36.20 m to the top of the section studied of 9°C. Oxygen stable isotopic analyses from the same species, measured through the same core intervals, did not exhibit a trend, but their values were indicative of normal marine salinities. Carbon stable isotope analyses, performed at the same time as the oxygen analyses, indicate that there may have been high productivity in the region of deposition of the Sand Hole Formation, implying deposition in a region of freshwater influence. However, C/N analyses indicated that the sediments in the Inner Silver Pit were deposited under fully marine conditions. In III ISI, both the Mg: Ca and Sr: Ca data suggested that salinity had increased upcore. Ilowever, there was a lot of scatter in the data, indicating that the estuarine environment, under which the palaeoecology suggests the sediments were deposited, was a highly fluctuating one. These data compare favourably with previously published records. Published partition coefficients were used to compare the trace element data obtained to mean river and seawater values.
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Sprenk, Daniela [Verfasser], Michael E. [Akademischer Betreuer] Weber, Martin [Akademischer Betreuer] Melles, and Gerhard [Akademischer Betreuer] Kuhn. "Palaeoclimate and Ice-Sheet Dynamics in the Southern Ocean / Daniela Sprenk. Gutachter: Michael E. Weber ; Martin Melles ; Gerhard Kuhn." Köln : Universitäts- und Stadtbibliothek Köln, 2013. http://d-nb.info/1044679948/34.
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