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The north-east Atlantic margin (NEAM) is important for hydrocarbon exploration because of the growing evidence of hydrocarbon reserves in the region. However, seismic exploration of the sub-surface is hampered by large deposits of flood basalts, which cover possible hydrocarbon-bearing reservoirs underneath. There are several hypotheses as to why imaging beneath basalt is a problem. These include: the high impedance contrast between the basalt and the layers above; the thin-layering of the basalt due to the many flows which make up a basalt succession; and the rough interfaces on the top-basalt interface caused by weathering and emplacement mechanisms. I perform forward modelling to assess the relative importance of these factors for imaging of sub-basalt reflections. The boundary element method (BEM) is used for the rough-interface modelling. The method was selected because only the interfaces between layers need to be discretized, in contrast to grid methods such as finite difference for which the whole model needs to be discretized, and so should lead to fast generation of shot gathers for models which have only a few homogeneous layers. I have had to develop criteria for accurate modelling with the boundary element method and have considered the following: source near an interface, two interfaces close together, removal of model edge effects and precise modelling of a transparent interface. I have improved efficiency of my code by: resampling the model so that fewer discretization elements are required at low frequencies, and suppressing wrap-around so that the time window length can be reduced. I introduce a new scheme which combines domain decomposition and a far-field approximation to improve the efficiency of the boundary element code further. I compare performance with a standard finite difference code. I show that the BEM is well suited to seismic modelling in an exploration environment when there are only a few layers in the model and when a seismic profile containing many shot gathers for one model is required. For many other cases the finite difference code is still the best option. The input models for the forward modelling are based on real seismic data which were acquired in the Faeroe-Shetland Channel in 2001. The modelling shows that roughness on the surface of the basalt has little effect on the imaging in this particular area of the NEAM. The thin layers in the basalt act as a low-pass filter to the seismic wave. For the real-data acquisition, even the topbasalt reflection is a low frequency event. This is most likely to be due to high attenuation in the layers above the basalt. I show that sea-surface multiple energy is considerable and that it could mask possible sub-basalt events on a seismic shot gather, but any shallow sub-basalt events should still be visible even with the presence of multiple energy. This leaves the possibility that there is only one major stratigraphic unit between the base of the basalt and the crystalline basement. The implication of the forward modelling and real data analysis for acquisition is that the acquisition parameters must emphasize the low frequencies, since the high frequencies are attenuated before they even reach the top-basalt interface. The implication for processing is that multiple removal is of prime importance.

Ecologism is a political ideology that emerged in the 1970s. It challenged the neoliberal privileging of economic growth over environmental protection and a narrow conception of the self as autonomous, rational and self-interested. Ecologism’s normative challenge has grown quiet as it became perceived as too inward looking and focused on the self, rather than engaged with issues such as climate change that now preoccupy green political thought. However, in the early 21st century, neoliberalism now dominates western democracies. This turn away from the self and normative opposition to neoliberalism has clearly not furthered the environmental cause, and so there is a need to return to re-politicise the ontological arguments of ecologism. A small number of green political theorists have begun to look towards the Thomistic Aristotelianism of Alasdair MacIntyre and this thesis seeks to add to their number. I argue that MacIntyre’s work concerning the self as dependent rational animal, and arguments for the political and social structures that support this self, can be used to affirm and reengage ecological arguments with politics. MacIntyre’s thought moves ecologism away from its “inward-turn”, concerned with the self’s personal experience of the environment, to a collective politics that looks outwardly to challenge the dominant neoliberal order. In bringing ecologism into conversation with MacIntyre’s philosophy, the original contribution I offer ecological political theory is two-fold. Firstly, the virtues of acknowledged dependence can be used to reflect substantive concern for the environment within political deliberation. Secondly, I develop MacIntyre’s conception of localized deliberative democracy. In order to counter claims that such localization is naïve, I bring MacIntyre’s ideal into conversation with Murray Bookchin’s model of municipal libertarianism and consider two real world examples: Rojava in northern Syria and the ‘Idle no More movement’ in Canada. These examples offer hopeful evidence that decentralised deliberative politics, starting from acknowledging our dependence, can oppose the hegemony of neoliberalism both socially and ecologically.