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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Depositional character of "syn-rift" deep-water deposits : a case study from the upper Jurassic Buzzard turbidite system

McKinnon, Mark January 2013 (has links)
The Buzzard Field lies within outer Moray Firth (Central North Sea) and is part of a Late Jurassic, syn-rift, deep water depositional system that comprises deep-water sandstones interbedded with ‘expanded’ hemipelagic mudstones, and mud-rich mass transport deposits, sourced from basin margin highs. Sandstones are interpreted mainly as the deposits of large volume, sustained high density turbidity currents sourced axially through linear systems aligned with the west-to-east regional structural trend. The extensive core database has formed the basis for the sedimentological interpretation of the field, which has been extended into uncored wells using a new lithofacies recognition technique pioneered within this study. Dipmeter data have been used to supplement lithofacies interpretation of conventional wireline logs. Neural net analysis of these log signatures, calibrated to core description, has revealed the lithofacies present in uncored section and allowed an improved understanding of lithofacies variability across the field. The depositional history of the Buzzard system, based on fieldwide correlation and a regional biostratigraphic framework, is interpreted to consist of seismically triggered flow events, which were initially confined by structurally generated basin floor topography; later, more frequent flows encountered simpler bathymetry and were weakly confined, depositing lobe shaped sandstone bodies. This sequence is summarised by several depositional cartoons. The field is described here as a three-way stratigraphic trap with a down-dip oil-water contact despite being deposited in a tectonically active period. The sedimentological factors that contribute to the trapping mechanism are discussed in detail including: flow divergence; slope angle; and basin margin interaction. This study has implications for the interpretation of flow processes in (and sediment delivery mechanisms to) the deep-water environment, recognition of lithofacies from wireline data, and for future exploration in syn-rift, deep-water settings. Analysis of the extensive core dataset has revealed that sands were transported to the deep basin as part of large-scale flow events and were deposited rapid mainly through fallout from suspension. These infrequent but catastrophic flow events moved large volumes of sediment from a shallow marine staging area to the deeper setting, eventually depositing a characteristically thick-bedded sandstone succession. The coarsest-grained portions of individual event beds have been identified as high permeability layers and are essential to understand from a production perspective. The geometry and distribution of these high permeability zones is controlled by depositional process and are iii located in the axial, updip parts of event beds. Therefore, accurate correlation of thick event beds is particularly important for reservoir characterisation. The updip depositional limit of these sands defines a stratigraphic pinchout margin that corresponds to an Upper Jurassic isochron which may be used to define the limit of Upper Jurassic sandstones in other areas of the North Sea. Furthermore, the pinch out limit is defined at a transition from high structural complexity updip to lower complexity downdip. Crucially, this transition allowed flows that were routed through the complex updip palaeobathymetry to diverge downdip, thus rapidly depositing their sediment load. Well established sediment gravity flow pathways such as those interpreted to feed the Buzzard basin are rare in the Upper Jurassic of the North Sea. Despite that, this combination of flow pathway, shallow marine source area and structural configuration we essential factors in producing a reservoir of the quality of Buzzard;similar tectono-stratigraphic settings may also produce Buzzard-style reservoir and should be considered exploration targets.
2

Marine geology and sedimentation of Milne Bay, New Guinea

Jongsma, D. January 1970 (has links)
Thesis (M.S.)--University of New South Wales, 1970. / Map on 1 folded leaf in pocket. Includes bibliographical references (leaves 68-79).
3

Late Holocene geologic, oceanographic and climate history of an anoxic fjord : Effingham Inlet, West Coast, Vancouver Island /

Dallimore, Audrey, January 1900 (has links)
Thesis (Ph. D.)--Carleton University, 2001. / Includes bibliographical references (p. 274-292). Also available in electronic format on the Internet.
4

Late Quaternary evolution of the northwest Florida coast and margin development of a conceptual model for identifying and characterizing shelf sediment deposits /

Koch, Jennifer Lynn, Donoghue, Joseph F. January 2006 (has links)
Thesis (Ph. D.)--Florida State University, 2006. / Advisor: Joseph Donoghue, Florida State University, College of Arts and Sciences, Dept. of Geological Sciences. Title and description from dissertation home page (viewed Dec. 4, 2006). Document formatted into pages; contains xxi, 292 pages. Includes bibliographical references.
5

Late holocene climate change of Frederick Sound, British Colombia, Canada /

Wigston, Andrew P., January 1900 (has links)
Thesis (M.Sc.) - Carleton University, 2006. / Includes bibliographical references (p. 80-95). Also available in electronic format on the Internet.
6

Late Quaternary marine, deltaic and fluvial deposits, Kanairiktok Valley, coastal central Labrador /

Awadallah, Sherif Abdel Monem, January 1992 (has links)
Thesis (M.Sc.)--Memorial University of Newfoundland, 1994. / Typescript. Bibliography: leaves 195-210. Also available online.
7

Allostratigraphic interpretation of a modern coarse clastic barrier complex : depositional facies, processes and relative sea level relationships /

Davis, Laurence H. M., January 2003 (has links)
Thesis (Ph.D.)--Memorial University of Newfoundland, 2003. / Bibliography: leaves 159-171. Also available online.
8

The impact of microbial extracellular polymeric substances on sediment stability

Lubarsky, Helen V. January 2011 (has links)
The main objective of this thesis is to investigate the impact of microbial extracellular polymeric substances (EPS) on sediment stability and the related factors which influence “biogenic stabilisation” as a basis to the prediction of sediment erosion and transport. The ability to make direct and sensitive measurements of the physical properties of the biofilm is a critical demand to further understanding of the overall biostabilisation processes. Therefore, attention has been focused on developing a new technique, Magnetic Particle Induction (MagPI) for measuring the adhesive properties of the biofilm. MagPI determines the relative adhesive properties or “stickiness” of the test surface, whether a biofilm, a sediment or other submerged material. The technique may have future applications in physical, environmental and biomedical research. Newly developed Magnetic Particle Induction(MagPI) and traditional techniques Cohesive Strength Meter (CSM) for the determination of the adhesion/cohesion of the substratum were used to assess the biostabilisation capacity of aquatic microorganisms. Whilst these devices determine slightly different surface properties of the bed, they were found to complement each other, increasing the range of measurements that could be made and presented a strong correlation in the overlapping portion of the data. It is recognized that microorganisms inhabiting natural sediments significantly mediate the erosive response of the bed (“ecosystem engineers”) through the secretion of naturally adhesive organic material (EPS: extracellular polymeric substances). Interactions between main biofilm consortia microalgae, cyanobacteria and bacteria in terms of their individual contribution to the EPS pool and their relative functional contribution to substratum stabilisation were investigated. The overall stabilisation potential of the various assemblages was impressive, as compared to controls. The substratum stabilisation by estuarine microbial assemblages was due to the secreted EPS matrix, and both EPS quality (carbohydrates and proteins) and quantity (concentration) were important in determining stabilisation. Stabilisation was significantly higher for the bacterial assemblages than for axenic microalgal assemblages. The peak of engineering effect was significantly greater in the mixed assemblage as compared to the bacterial and axenic diatom culture. This work confirmed the important role of heterotrophic bacteria in “biostabilisation” and highlighted the interactions between autotrophic and heterotrophic biofilm components of the consortia. An additional approach, to investigate the impact of toxins on biostabilisation capacity of aquatic organism was performed on cultured bacterial and natural freshwater biofilm. The data suggest a different mode of triclosan (TCS) action ranging from suppressing metabolisms to bactericidal effects depending on the TCS concentration. The inhibitory effect of triclosanon bacterial and freshwater biofilms was confirmed. This information contributes to the conceptual understanding of the microbial sediment engineering that represents an important ecosystem function and service in aquatic habitats.
9

Albian-Cenomanian foraminifera in northeastern British Columbia and western Alberta: paleoecology and integration of biostratigraphy with allostratigraphy /

Mans, David, January 1900 (has links)
Thesis (M.SC.) - Carleton University, 2007. / Includes bibliographical references (p. 146-160). Also available in electronic format on the Internet.
10

An investigation of Scripps Submarine Canyon its geology, sedimentary regime, and bubbling gases /

Rindell, Anders Koria. January 1991 (has links)
Thesis (M.S.)--San Diego State University, 1991. / Includes bibliographical references (leaves 124-133).

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