The Gorringe Bank region is located at the eastern end of the Azores-Gibraltar plate boundary, which plate kinematic studies show to progressively change from extension at the Azores, through pure right lateral strike slip at the Gloria fault to compression at Gibraltar. The region is dominated by high relief (4-5 km), highly deformed, uncompensated, ENE-WSW trending seamounts and intervening abyssal plains with basin sediment thicknesses in excess of 4 km and minimal surface deformation. Gorringe Bank, which was formed by overthrusting of the African plate upon the Eurasian plate at about 10 Ma along the plate boundary, is supported in part by exure of the Eurasian plate, as indicated by pre-loading sediments and basement to the north which are tilted towards Gorringe Bank. Broken plate models show the Eurasian plate to have an elastic thickness of about 35 km which is in agreement with that expected for the crustal age (130-135 Ma) at the time of loading. Coral Patch Ridge was formed by a combination of thrust faulting and whole crustal buckling resulting from the past 20 Ma compression and was partially uplifted before deposition of an olistostrome in the Middle Miocene. Recent compressional deformation is distributed over a wide region, as indicated by the dispersed shallow seismicity and has a trend which rotates from approximately N45oE to N70oE from west to east across the region, near perpendicular to westward verging plate motion vectors. The majority of extensional and strike-slip deformation is explained by a regional strike-slip strain ellipse model, including an antithetic NNE-SSW strike slip fault between Gettysburg and Hirondelle seamounts which marks the boundary between the Eastern and Western Horseshoe Basins. Isostatic models for the Madeira-Tore Rise, which initially formed at the Mid Atlantic Ridge, give an elastic thickness of approximately 15 km indicating that significant material was added to the Rise as it moved away from the Ridge.

A quantitative forward model has been developed to investigate the controls on the deposition, erosion, and preservation of passive rift margin stratigraphy. The model includes thermal subsidence, variable absolute sealevel, flexural isostasy, subaerial and submarine deposition on fluvial and marine equilibrium profiles, and the facility to vary sediment supply through time. Results from the quantitative model can be used to reproduce elements of the sequence stratigraphic depositional model. Conducting sensitivity tests demonstrates that variables such as sediment supply and fluvial profile behaviour are likely to be of equal importance to thermal subsidence and eustasy in passive margin stratigraphy. Sensitivity tests with the quantitative model also demonstrate the problems associated with attempting to use a discretised stratigraphic model to investigate unforced cyclicty resulting from complex interactions in stratigraphic systems. Although the model appears capable of producing such unforced cyclical behaviour, this cyclicity is shown to be due to a numerical instability within the model which occurs with certain initial conditions and assumptions. The applicability of the model to observed stratigraphy is tested by comparing specific model output to patterns of stratigraphy from the North American Atlantic margin. The results from this test demonstrate that although the model is in many respects simplistic when compared to the complexities of natural systems, it is nevertheless capable of reproducing some of the basic elements of the observed stratigraphic patterns.

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The whole Mediterranean was a site of carbonate deposition during Miocene. Unlike other Miocene basins in the Mediteranean, the importance of Mut Basin lies in its tectonically undisturbed nature that provides excellent exposures to study sequence stratigraphic architecture and carbonate sedimentology. Opening of Mut Basin began during Oligocene / carbonate deposition started during Early Miocene. The pre-Miocene rocks are characterized by (from bottom to top), 1. ophiolites and Mesozoic limestones, 2. Eocene lacustrine limestones, 3. Burdigalian fluvial sandstones and conglomerates. The carbonate deposition began in Miocene, settling on the preexisting topography. Carbonates have been deposited in a ramp setting, where several sequences formed. The ramp was partly subaerially exposed during Early Miocene due to relative sea level fall / however, no significant lowstand deposits were developed. The subsequent sea level rise caused transgressive deposits to overlie this ramp sequence. The patch reefs on this ramp exhibit a keep-up type depositional setting. As the transgression continued, the basin topography controlled the type of depositional setting. Hence, a transition from ramp to reefal margin type setting occurred. In landward direction the topographically low areas became back reef lagoonal part of this reefal margin. A mature reefal environment formed during highstand times, which is characterized by a rich coral fauna / algal flora in the basinward side. Some of the patch reefs of the ramp transformed into pinnacle reefs. Diagenetic alterations are mostly related to duration and degree of sea level fall, and therefore related to sequence boundaries. The Miocene carbonates in the study area consist of six sequences which may be used for correlation with other Miocene carbonates of the Mediterranean region.

The Oligocene Brac Formation is the oldest part of the Bluff Group that is exposed on Cayman Brac. Sediments of the Brac Formation were deposited on a small, open bank in shallow marine waters. Today, the formation is composed of limestone, finely crystalline dolostone, and coarsely crystalline sucrosic dolostone. The Pollard Bay member, defined herein, comprises the sucrosic dolomite that is exposed only on the south coast of Cayman Brac. Changes in sea level and subsequent groundwater chemistry mediated a complex diagenetic evolution that is responsible for the lithological heterogeneity that now characterizes the formation. Field, petrographic, and geochemical analyses indicate that dolomitization was probably mediated by normal to slightly modified seawater. Multiphase dolomite crystals represent different stages of textural and geochemical maturity, and attest to time-transgressive dolomitization processes that evolved in various hydrologic regimes through time.

The Late Neogene sedimentary sequence of the Murray Basin provides an excellent opportunity to examine paleoenvironmental change across southeastern Australia. A detailed stratigraphic analysis of sediments deposited within the basin in the last 10 Ma was undertaken to assess the influence of tectonic and eustatic processes on deposition. / Stratigraphic observations and radiogenic isotope analysis reveals the onset of deposition by 7.2 Ma with a transgressive episode that deposited the marine marls of the Bookpurnong Beds. Deposition was restricted to the central and eastern parts of the basin due to the Hamley Fault. In the west, subsurface elevation contours indicate the presence of incised paleodrainage channels above Miocene limestones, which facilitated the formation of a large estuary system at 5.3 Ma. The sediments of the Norwest Bend Formation were deposited within this western region, while further east, the Loxton-Parilla Sands strandplain deposited over 214 coastal ridges. The basal parts of this unit occur as lateral equivalents to the sediments of the Lower Norwest Bend Formation (in the west). Topographic and magnetic data reveal that tectonism was active during this period and resulted in the erosion and truncation of strandlines. / Tectonic evidence and an estimated minimum 28,037 year cyclicity between strandline sets, suggests that the Loxton-Parilla Sands strandlines do not represent an unbroken record of glacioeustatic change. The subaerial exposure of these sediments at approximately 3.0 Ma caused the formation of a calcareous karst above the Norwest Bend Formation and a ferruginous and/or silicious cap (the Karoonda Surface) above the Loxton-Parilla Sands. The stratigraphic position of these surfaces are indicative of a regional widespread unconformity. / The Douglas-Blackburn paleodrainage system in western Victoria was dammed during the Mid-Late Pliocene by uplift associated with the Padthaway High, which caused the formation of a 400,000 km2 lacustrine system, known as Lake Bungunnia. Topographic analysis indicates that Lake Bungunnia comprised at least four distinct sub-basins with water depths of up to 30 metres, with lake shorelines indicating that active tectonism occurred during this period. The resulting lack of sediment input to the coast caused the formation of the Kanawinka Escarpment, a large erosional scarp along the southern margin of the Padthaway High. / The geomorphology of the modern Murray Basin can be directly attributed to the demise of the Lake Bungunnia system. Movement along the Morgan Fault in the west at approximately 700 Ka, resulted in the draining and progressive drying of Lake Bungunnia as a breach was created along the Padthaway High. The Murray River gorge as observed today was incised following this episode. The modern Murray River (and playa lakes such as Lake Tyrell) occupy the lowest elevations along the former sub-basins of Lake Bungunnia. / The Late Neogene sedimentary sequence across the Murray Basin illustrates a complex interaction of eustatic and tectonic processes on deposition. Sedimentation within strandline, estuarine and lacustrine systems, particularly in the western Murray Basin, display evidence of significant tectonic control. This highlights the important role that neotectonic processes have played in shaping southeastern Australia.

Thèse (M.sc.A.)- Université du Québec à Chicoutimi, 1981. / "Mémoire présenté en vue de l'obtention du grade de maître en sciences appliquées" CaQCU Document électronique également accessible en format PDF. CaQCU

Mémoire (M. Sc. A.)- Université du Québec à Chicoutimi, 1981. / Quatre cartes géologiques sur feuillets pliés, en pochette. "Mémoire présenté en vue de l'obtention de la maîtrise es sciences appliquées" CaQCU CaQCU Document électronique également accessible en format PDF. CaQCU

Thèse (D.R.Min.) -- Université du Québec à Chicoutimi, programme extensionné à l'Université du Québec à Montréal, 2003. / Bibliogr.: f. 203-204. Document électronique également accessible en format PDF. CaQCU

Thesis (M.S.)--West Virginia University, 2004. / Title from document title page. Document formatted into pages; contains xiv, 225 p. : ill. (some col.), maps (some col.). Includes abstract. Includes bibliographical references (p. 113-116).