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Offshore to the west of the Scottish mainland resides a series of Late Palaeozoic to Mesozoic rift basins, which have been the target of small-scale petroleum exploration from 1968 to the present day. The series of 14 basins, which run from the Minch Basin, offshore northwest Scotland to the Portpatrick Basin, located between southwest Scotland and Northern Ireland, have been here collectively named the 'Inshore West Coast Basins' and are the primary focus for this PhD. The geological development, structure and stratigraphy of each of the Inshore West Coast Basins has been assessed as well as the basins potential for containing a working petroleum system. The potential for each basin to contain petroleum system elements such as source rock, reservoir rock, seal and traps have been reviewed alongside an assessment of the risks to finding commercial sized petroleum accumulations. To assess the petroleum potential of each basin, well data, borehole data, seismic reflection data and gravity and magnetic data have been evaluated alongside previously published geological studies. Further in-depth geological and prospectivity studies were undertaken for four of the basins which showed potential for containing petroleum reserves (the Sea of Hebrides Basin, Minch Basin, Larne Basin and the Portpatrick Basin). The conclusion drawn from these studies is that despite each basin containing petroleum shows and a working petroleum system, the potential for the basins to contain commercial sized oil or gas accumulations is low. Overall, the potential for discovering petroleum accumulations within the Inshore West Coast Basins is poor. The main risks to prospectivity are the low maturity of the source rocks, particularly the Jurassic source rocks, the risk of trap breach due to the basins undergoing numerous exhumation events and the potential for biodegradation or flushing of any petroleum accumulations due to the shallow burial of potential reservoirs.

The eruption of volcanic rocks into a sedimentary basin is often related to dynamic changes in basin evolution and, hence, the sedimentary systems and tectonic evolution of a basin. However, the stratigraphic link between volcanism and sedimentation is often poorly understood. This thesis examines contrasting sedimentary basins, the Faroe-Shetland Basin of the NE Atlantic and the Cooper and Eromanga Basins of Central Australia, to investigate how volcanism affected the sedimentary, tectonic and petroleum evolution of these basins. In 2004 a major oil and gas discovery was made within the volcanic succession of the Faroe-Shetland Basin, the Rosebank Field. Unusually, the reservoir was a series of intra-basaltic fluvial to shallow marine intervals, giving rise to a new hydrocarbon play concept. Despite the identification of an intra-lava incised drainage system running parallel to the Rosebank field, the play fairway remained poorly defined. However, the eruption of lavas within the Faroe-Shetland Basin is related to the formation of an extensive incised drainage network, providing a potential source of clean sand for the Rosebank Field. This thesis first attempts to understand the controls on intra-basaltic sediments in the CamboRosebank region before forming a detailed stratigraphic link between the volcanic succession and dynamic changes in basin evolution in the Upper Palaeocene and Lower Eocene of the Faroe-Shetland Basin. Dynamic uplift and subsidence are then related to the evolution of the Proto-Icelandic Plume in the Northeast Atlantic. In contrast to the tectonically complex Faroe-Shetland Basin, the Cooper and Eromanga Basins are stacked intracratonic sag basins within Central Australia. Igneous rocks have been recognised in the region, however, their extent and age have remained unclear. This thesis details the extent, character, and age of predominantly monogenetic igneous rocks within the Cooper and Eromanga Basins, recognising a volcanic province in the region. The stratigraphic significance of the volcanism in Central Australia and its relation to the evolution of Australia throughout the Jurassic is detailed. Locally, volcanism is intimately linked with basin structure through the exploitation of pre-existing structural weaknesses. A better understanding of the basin structure can, therefore, lead to an indepth understanding of the distribution of volcanics and intra-basaltic sediments in sedimentary basins. Regionally, the emplacement of volcanics in a sedimentary basin is intrinsically linked to the tectonic evolution of a region. Detailing the volcanic evolution of a basin can, therefore, reveal tectonic events previously hidden within the complex framework of sedimentary basins.

Turbidite sheet systems have various depositional architectures, whose differences are likely to be the result of variations in flow efficiency and degree of confinement. Recent depositional models on turbidite sheet systems have been built up largely based on unconfined sandy systems. A more comprehensive framework is needed to encompass all turbidite sheet systems. The research is fieldwork-based and focuses on comparing depositional architecture differences of five contrasting units that exhibit deposits of flows with differing flow efficiency and confinement. Four of these occur in the Mississippian/Pennsylvanian Paganzo Basin in NW Argentina and one occurs in the late Cretaceous age Magallanes Basin in Chile. The thesis established a semi-quantitative way of assessing the degree of confinement in turbidite sheet systems by dividing the flow efficiency by the maximum preserved basin dimensions. Individual beds are found to obey power law decay in highly confined turbidite sheet systems, whereas they obey a logarithmic decay in unconfined and loosely confined systems. In highly confined settings, individual beds stack vertically, whereas in unconfined systems, individual beds stack compensationally. Five facies associations (axis, off-axis, lateral fringe, distal-fringe and frontal fringe) have been identified in unconfined systems and they follow linear transitions from axis to distal fringe; only one facies association has been identified in confined turbidite sheet systems and does not show spatial variation. The preexiting 'lobe' model and terminologies only apply to unconfined sheet systems. Below the hierarchical level equivalent to lobe complex, degree of confinement is the dominant controlling factor of turbidite sheet systems. The number of beds are much less in confined systems than that in unconfined systems at a same hierarchical level, which may indicate that less frequent flows allow the larger flows. A comprehensive framework combing flow efficiency, degree of confinement, types of facies association and rate of facies associations has been established.

The crustal structure beneath the Cenozoic Niger Delta Basin has remained controversial and a challenging problem for regional basin evaluation. The high-resolution potential field data were evaluated using analytical, statistical and 2D forward modelling techniques with the aim of developing a better understanding of the origin and nature of the crustal structure and the location of the continent-ocean boundary (COB) within the Niger Delta. The analytical evaluations suggest that basement lineament trends of NE-SW, NNE-SSW and NW-SE in the study area are similar to the trends of the Pan-African events/orogeny (< 800 Ma). Two new intra-basement features were recognized, the Udi-Burutu and the Okigwe-Middleton intra-basement features, which provide fresh insights into the crustal nature of the Niger Delta. These features could have influenced the main boundary faults that provide migratory pathways for hydrocarbon or hydrothermal fluids. Mapping of the basement using a statistical method indicates that the thickness of the Cenozoic sediments varies from 10 km to less than 6.5 km with an average of 8 km. The average heat flow value (67 mWm⁻²) calculated in the Niger Delta area from geothermal gradient data, and thermal conductivity data lies within the average global heat flow for a typical continental crust. The 2D forward models show that the crustal thickness varies from 12 km at Okigwe area (NE) to about to about 24 km beneath Patani area at the centre of the delta to 12 km at Pennington area (SW) near the coastline of the delta. The depth to Moho estimated in the study area ranges from about 24 km at Okigwe area to more than 30 km at Patani area and to about 25 km at Pennington area. The Okigwe and/or Pennington area could mark the start of hyper-extended/transitional crust that lies beneath the Niger Delta. Thus, it is hereby suggested that the onshore Niger Delta Basin generally is underlain by thin continental crust and not oceanic crust as previously argued and the COB is observed at the offshore segment of the delta. This implies that the Onshore-offshore portion of the Niger Delta is underlain by the continent-ocean transition (COT) structure. The crustal structure of the Cenozoic Niger Delta Basin suggests post-rift stage characteristics similar to the pure shear model mechanism for the evolution passive continental margins. In reconstruction of the South Atlantic, the Chain and Charcot fracture zones beneath the Niger Delta exhibit dextral shear movement thereby suggesting a right-angled bend connecting Africa and South America continental margin due to pre-existing stress patterns within this part of Gondwanaland.

The passive margins of west Greenland and Baffin/Labrador (sedimentary basins and onshore topography therein) developed mainly as a result of Late Mesozoic and Cenozoic rifting processes in the Davis Strait area. The origin and age of topography along the west Greenland margin is a matter of continued debate. Analysis of seismic reflection profiles and 1-D modelling of wells along the Greenland margin of Davis Strait demonstrate that the data are consistent with a model of ancient continental topography affected by Late Cretaceous-early Palaeocene rifting followed by thermal subsidence, where offshore Neogene tectonic uplift is not required. First order analysis of apatite fission track data from southeast Baffin Island reveals that samples experienced contemporaneous cooling from an array of initial temperatures. 1-D modelling suggests that cooling through the partial annealing zone occurred over discrete periods ranging from 100 to 300 Ma. Modelling the 3-D exhumation of a heterogeneous crust demonstrates that some of the variability in observed fission track ages could be attributed to thermal crustal heterogeneity. The results show that the observed data are consistent with a simple exhumation scenario where the present-day high topography is a remnant of that created during Palaeoproterozoic orogenies. In view of new geophysical constraints and newly assessed well data, a number of the exploration wells located on the conjugate west Greenland and Baffin/Labrador margins have been re-modelled to determine whether any new insights might be derived. Model results imply that southeast Baffin area was subject to more intense rifting prior to the onset of magmatism in the early Palaeocene. This in turn suggests that magmatism in the area was related to rifting and not linked to the arrival of a mantle plume at the beginning of the Palaeocene. The thermal histories presented here are consistent with those required for hydrocarbon generation.

Samples of shallow-water carbonates were collected from Jurassic and Cretaceous Italian carbonate platforms and subjected to petrographic, diagenetic and chemostratigraphic analyses (87Sr/86Sr, δ13Ccarb, δ13Corg, δ18O). In general, the new chemostratigraphic data generated reflect trends established by previous work, some of which has been carried out on biostratigraphically calibrated reference sections. Consequently, chemostratigraphic correlations (87Sr/86Sr, δ13Ccarb) of isotope profiles taken from platform carbonates with well-dated reference sections have allowed the application of high-resolution dating frameworks to the biostratigraphically poorly constrained carbonate platforms. The increased resolution in dating of the Italian carbonate platforms has, furthermore allowed a detailed investigation into the facies response of these carbonate platforms to major geological events. In particular, platform responses to oceanic anoxic events and other periods of major perturbation in the global carbon cycle are analysed (early Toarcian, Aalenian-Bajocian, Oxfordian-Tithonian, Valanginian-Hauterivian, Aptian-Albian, Cenomanian-Turonian, Coniacian-Santonian). Lower Jurassic levels of the Trento Platform record platform devastation in the early Toarcian synchronous with a major negative δ13Ccarb excursion, followed by platform recovery synchronous with a pronounced δ13Ccarb positive excursion and return to background values. The Campania-Lucania Platform shows negligible response to the oceanographic events of the early Toarcian even though the characteristic carbon-isotope profile is readily identifiable. The Trento Platform drowned at approximately the Aalenian-Bajocian Stage boundary, synchronously with a reproducible negative followed by positive δ13Ccarb excursion, whereas the Campania-Lucania Platform underwent a facies transition from oolite to cyclically bedded micrite. The Friuli Platform showed negligible depositional response to the carbon-cycle perturbations of the Kimmeridgian-Tithonian, Valanginian-Hauterivian, Aptian-Albian and Cenomanian- Santonian (as registered in the δ13Ccarb record). The Campania-Lucania Platform registered flooding and increased levels of organic-matter preservation coincident with pronounced positive δ13Ccarb excursions at Cenomanian-Turonian and Coniacian-Santonian levels. Observations on the responses of carbonate platforms to oceanographic conditions during periods of global carbon burial lead to the conclusion that temperature excess is a hitherto neglected control on global carbonate accumulation rates.