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The Vestnesa Ridge, located off the west Svalbard margin, is a >60 km long ridge consisting of fine-grained sediments that host a deep-marine gas hydrate and associated seepage system. Geological and geophysical observations indicate the predominance of vertical fluid expulsion through fractures with pockmarks expressed on the seafloor along the entire ridge. However, despite the apparent evidence for an extended free gas zone (FGZ) below the base of the gas hydrate stability zone (BGHSZ), present-day seafloor seepage has been confirmed only on the eastern half of the sedimentary ridge. In this study, we combine the relationships between aqueous phase pressure, capillary pressure, sediment clay fraction, porosity, and total stress to simulate how much gas is required to open preexisting fractures from the BGHSZ towards the seafloor. Data from four specific sites with different lithology and pressure regime along the ridge are used to constrain the simulations. Results demonstrate that fracturing is favored from the FGZ (with gas saturations < 0.1 and gas column heights < 15 m) towards the seafloor. Neglecting the capillary pressure overpredicts the size of the gas column by up to 10 times, leading to erroneous maximum gas vent volume predictions and associated ocean biosphere consequences. Further parametric analyses indicate that variations in the regional stress regime have the potential to modify the fracture criterion, thus driving the differences in venting across the ridge. Our results are in line with independent geophysical observations and petroleum system modeling in the study area, adding confidence to the proposed approach and highlighting the importance of the capillary pressure influence on gas pressure.

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Noted scholars have argued that urbanisation in India is dysfunctional, sans industrialisation, dependent on a largely informal tertiary sector and totally unsustainable (Bhalla, 2004). I posit in this article that whatever the nature of urbanisation-'top heavy', tertiarised and sans industrialisation-India needs to promote urbanisation since we can demonstrate that poverty is better fought through urbanisation than by only focussing on rural development programmes and the population living in 600,000 small and scattered villages and hamlets which are unlikely to attract substantial private investment in public infrastructure. I argue in this article that there is a need to shift the policy focus to promoting urban growth, albeit the segment of the academia that discourses on over-urbanisation in India. The situation wherein the agricultural sector which has a share of 60 per cent employment and 25 per cent share in GDP (1999GDP ( -2000 is not sustainable. However, the current approach to urban residential planning that merely carves out areas required for high, middle and low income as well as economically weaker sections that leaves out perhaps more than 50 per cent of people living in urban areas must drastically change. At present, this segment of the city population occupies areas with very poor basic services.