This thesis presents one of the most comprehensive studies on submarine canyons yet. It integrates data on the geology, geochemistry, sedimentology and oceanography of the Nazaré, Setúbal and Cascais canyons, west Iberian margin, in order to constrain the processes and controls …
It has long been recognised that some oceanic regions have persistently low chlorophyll levels, even though inorganic nutrients are plentiful. Studies have shown that these high-nutrient, low-chlorophyll (HNLC) areas are depleted in iron, which is an essential micronutrient for …
The Central Indian Ridge (CIR) between 18° and 21°S shows significant morphological variation at a relatively constant spreading rate (between 47 and 51mmyr-1). High resolution TOBI sidescan sonar data (cruise CD127) and multibeam bathymetry data (Magofond 2 cruise), complemente…
Ocean fronts are narrow zones of intense dynamic activity that play an important role in global ocean-atmosphere interactions. Of particular significance is the circumglobal frontal system of the Southern Ocean where intermediate water masses are formed, heat, salt, nutrients an…
The Lumwana Cu±Co deposits Malundwe and Chimiwungo are examples of pre-Katangan mineralized basement that are located in the Domes Region of the Lufilian Arc, an arcuate North neo-Proterozoic fold belt, which hosts the Zambian and Congolese deposits that make up the Central Afri…
This thesis investigates the role of submarine hydrothermal vents in the global marine Fe budget. While debate continues over the sources of dissolved Fe to the global deep-ocean dissolved Fe budget, it had been presumed, until recently, that all the Fe emitted from hydrothermal…
Understanding the effect of physical forcing on estuarine functioning is of major importance to determine the rate of exchange of water, sediments, pollutants and nutrients between the continent and the ocean. The combination of numerical models and discrete datasets is used to …
The Southern Ocean plays a major role in the global overturning circulation, providing an important route for the return flow of deep water subducted in the North Atlantic. The World Ocean Circulation Experiment (WOCE) provided an unprecedented picture of the state of the world’…
Holothurians play an important role in carbon cycling. They dominate the abyssal oceanic megabenthos, reworking large amounts of organic matter. Holothurians require essential organic nutrients, such as carotenoids for their reproduction. Enhanced carotenoid concentration in the…
Marine dinoflagellates are an ecologically important phytoplanktonic group that accounts for two thirds of all known harmful algal bloom (HAB) species. This study explores the population ecology of Lingulodinium polyedrum (F. Stein) J.D. Dodge, a common bloom-forming dinoflagell…
The Middle Eocene (37 to 49 million years ago, Ma) was characterised by warmer global temperatures and higher atmospheric carbon dioxide (pCO2) levels than today with only small/non-existant icesheets. Because predicted pCO2 levels for the coming century have not been seen on Ea…
The eastern equatorial and tropical Pacific regions are areas of significant carbon fluxes from the atmosphere to the ocean interior. Changes in the function of marine biogeochemical cycles in this region potentially exert an important control on global climate. Understanding co…
Information on the concentration and distribution of dissolved methane (CH4), together with other geochemical tracers, in real time is of great value in detecting, monitoring, and understanding the functioning of hydrothermal plumes. Water column anomalies of light transmission,…