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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

Tectonism and sedimentation in the Jeanne d'Arc Basin, Grand Banks of Newfoundland

Sinclair, Iain K. January 1994 (has links)
The Jeanne d'Arc Basin, offshore eastern North America, is ideally situated to allow an assessment of the rifting history of the North Atlantic borderlands. Structures and the sedimentary fill of this basin record the occurrence of three main episodes of Mesozoic rifting. During the first episode in Late Triassic to Early Jurassic times, series of NE-SW trending, en echelon, normal faults formed in the Grand Banks of Newfoundland area. A second episode of tectonism began in the latest Oxfordian, while rifting of the upper crust characterized by the growth of northerly-trending faults occurred from the Tithonian to the Early Valanginian. The third tectonic episode began during the Barremian, while mid-Aptian to late Albian rifting resulted in growth of NW-SE-trending ("trans-basin") normal faults. A few major faults of this latter age and orientation, such as the Spoonbill fault and part of the Egret fault, are continuous from the pre-Mesozoic basement through Upper Triassic to Lower Cretaceous strata. The Spoonbill fault acted as a headwall fault, marking a southern limit to crustal extension of the Grand Banks area during this third rift episode. Transpressional and transtensional structures developed during mid-Aptian to late Albian rifting at restraining and releasing bends. These fault bends were created by oblique-slip reactivation and linkage of the previously-formed NE-SW-trending, en echelon faults in response to a ninety degree rotation of extensional stress axes between the first and third Mesozoic rift episodes. Similar lithostratigraphic architectures observed in the Jeanne d'Arc, Porcupine (Irish Continental Shelf) and Outer Moray Fifth (North Sea) basins support a regional model of sedimentation controlled by progressive changes in subsidence during the most widely recognized extensional episode, that which spanned the Late Jurassic to Early Cretaceous boundary. Subsidence rates began to vary across broad areas but without significant fault block rotation during a latest Oxfordian through Kimmeridgian "onset warp" phase, resulting in deposition of a lower interval of organic-rich source rocks. Conglomerates and/or sandstones were widely deposited at the start of rift deformation during the early Tithonian, while palaeoenvironments ranged from alluvial and braid plain to submarine fan. These basal sediments fine up a second layer of commonly organic-rich shales and marlstones. Sediments from all three basins show evidence of decreasing water depth, increasing oxygen levels and increasing grain size on basin margins during the final stages of this rift episode. Syn-rift subsidence rates are interpreted to have increased from the time of fault initiation to amid-rift peak. Subsidence is considered to have then slowed during the latest phase of this syn-rift episode, resulting in development of a base Late Valanginian break-up unconformity.
2

Depositional environments of the St. Peter sandstone of the Upper Midwest

Winfree, Keith Evan. January 1983 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1983. / Typescript. Includes bibliographical references (leaves 108-114).
3

Depositional environments of the St. Peter sandstone of the Upper Midwest

Winfree, Keith Evan. January 1983 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1983. / Typescript. Title from title screen (viewed Sept. 20, 2007). Includes bibliographical references (leaves 108-114). Online version of the print original.
4

Stratigraphy and sedimentation of the Yaquina formation, Lincoln County, Oregon.

Goodwin, Clinton John. January 1973 (has links)
Thesis (M.S.)--Oregon State University. / Part of illustrative matter in pocket. Includes bibliographical references (leaves 98-103). Also available via the World Wide Web.
5

Palynological, stratigraphic and chemical analyses of sediments in the Lothians with particular reference to the Lateglacial

Alexander, Alan John January 1985 (has links)
Palynological and stratigraphic investigations have been conducted on sediment cores for three sites in Lothian Region, Scotland: Balgone House, Broxmouth and Corstorphine. All phases of the Lateglacial period, as far as they are manifested in the Lothians at the sites studied, have been investigated with particular reference to the Younger Dryas, the main Interstadial, or Allerod, and also the evidence for the colder conditions that preceded it which are presumed to represent Older Dryas-type vegetation. Further light has been cast on the development of the Postglacial broad - leaved forests. The Cambridge computer program POLLDATA MKV was used to perform the necessary calculations and controlled a graph plotter to generate pollen diagrams. A series of subroutines is described that translated the calls to the Cambridge graphics subroutine library. This may serve as a model for other installations. Objective numerical zonation methods are applied to the pollen data. These methods are used not only to zone the pollen series but also to aid in the generation of hypotheses regarding vegetation changes. Chemical analyses of the sediments from Balgone House were undertaken. The results obtained are at variance with those from published work and it is proposed that the reason is that the chemical pre-treatment of samples employed locally may be less efficient in leaching the cations from the mineral fraction.
6

The stratigraphy and Late Pleistocene sedimentological history of the Lomonosov Ridge-Makarov Basin, central Arctic Ocean

Morris, Thomas Henry. January 1983 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1983. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 97-100).
7

Escarpement de faille synsédimentaire : perturbation des écoulements gravitaires sous-marins et détermination de la cinématique des failles /

Pochat, Stéphane. January 2003 (has links)
Thesis (doctoral)--Université de Rennes I, 2003. / Errata sheets inserted. Includes bibliographical references (p. 239-253, 266-270). Also available on the Internet.
8

Syn-orogenic slope and basin depositional systems, Ozona sandstone, Val Verde Basin, southwest Texas /

Hamlin, Herbert Scott, January 1999 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 1999. / Vita. Includes bibliographical references (leaves 128-134). Available also in a digital version from Dissertation Abstracts.
9

The sedimentology and stratigraphy of the Morrison Formation (Upper Jurassic) in northwestern Colorado and northeastern Utah

Dawson, James C. January 1900 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1970. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
10

The North Helvetic Flysch of eastern Switzerland : Foreland Basin architecture and modelling

Sinclair, Hugh D. January 1989 (has links)
The North Alpine Foreland Basin (NAFB) comprises sediments of late Eocene to middle Miocene age. The earliest deposits are the North Helvetic Flysch which are exposed in the regions of Glarus and Graubunden, eastern Switzerland. The Taveyannaz sandstones are the first thrust wedge (southerly) derived sediments of the North Helvetic Flysch. The Taveyannaz basin was divided into two sub-basins by a thrust ramp palaeohigh running ENE/WSW (parallel to the thrust front). Palaeocurrent directions were trench parallel towards the ENE. Sedimentation in the Inner basin (140m thick) is characterised by very thick bedded turbidite sands generated by thrust induced seismic events confined within the thrust-top basin. The Outer basin (240m min. thickness) comprises 10-15 sand packages (5-100m thick) formed by turbidite sands which are commonly amalgamated. Sedimentation in the Outer basin is considered to have been controlled by thrust-induced relative sea-level variations. The Inner basin underwent intense deformation at the sediment/water interface prior to the emplacement of a mud sheet over the basin whilst the sediments were partially lithified. Later tectonic deformation involved fold and thrust structures detaching in the underlying Globigerina marls. The stratigraphy of the NAFB can be considered as two shallowing upward megasequences separated by the base Burdigalian unconformity. This stratigraphy can be simulated by computer by simplifying the foreland basin/thrust wedge system into 4 parameters: 1) the effective elastic thickness of the foreland plate, 2) a transport coefficient to describe the erosion, transport and deposition of sediment, 3) the surface slope angle of the thrust wedge, 4) the thrust wedge advance rate. The Alpine thrust wedge underwent thickening during the underplating of the External Massifs at about 24-18Ma. This event is simulated numerically by slowing the thrust wedge advance rate, and increasing the slope angle and keeping all other parameters constant. This event causes rejuvenation of the forebulge, and erosion of the underlying stratigraphy, so simulating the base Burdigalian unconformity without recourse to eustasy or anelastic rheologies to the foreland plate.

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